30 de junio de 2022

The social/sexual psychology of primates, continued

(writing in progress)
(writing in progress)
I have previously mentioned that monkeys have remarkably little sympathy/empathy/compassion/altruism/caring-and-sharing. Further to this, I see that primates, in general, also have desultory courtship.
For example, a chimpanzee’s idea of courtship is to recline against a tree in the presence of females some distance away, display an erection, and then communicate threat to the female in question, so that she comes over to the male if she wishes to avoid being beaten up. In other words, the male not only lacks courtship, he has a kind of anti-courtship in which he compels the female to be performative by means of menacing innuendo.
Bonobos are famous for their genital contact. However, I suspect that if one reads more deeply on this topic one will find that even in the ‘love-ape’ there is minimal courtship. Using genital contact as a social lubricant does not necessarily mean that courtship is well-developed. I suspect that it is poorly developed in the bonobo, as in other primates.
In orang-utans, fully mature males are attractive to females on account of their great size and secondary sexual features. However, they do not need to court. The other males (adult and sexually motivated but not fully mature) routinely rape females. Either way, courtship is not something that orang-utans seem to practise.
These are just initial examples.
Hans Kummer makes this point specifically for the hamadryas baboon, in his book 'The Sacred Baboon'. I.e. that Papio hamadryas (https://www.inaturalist.org/taxa/43535-Papio-hamadryas) lacks anything that can really be described as courtship, and is typical of monkeys and other primates in this way.

Again, in a way courtship is actually perverted in Old World monkeys including baboons: what happens is that males must copulate several times in fairly short succession (minutes but not hours apart) before ejaculation is triggered. I.e. far from engaging in ‘warming up’ of the female, or giving her ‘foreplay’, the masculine approach to mating is to ‘warm himself up’, with her as the sex-object. Furthermore, in the mounting position he places his whole weight on the female (which is usually half his body mass in baboons), by standing on her calves, not on the ground. Chivalry/gentlemanliness does not seem to be a concept for primates.
In Hans Kummer’s own words (page 221), and please bear in mind that he was the most rigorous or scientists:
“Courtship among higher primates is generally a rather shabby affair. There are very few exceptions such as the capuchin monkeys, where a couple cuff, chase, caress one another’s chest, sit close and seek each other’s eyes before they finally mate...But this pleasant state of affairs is all the female’s doing; before the male joins in she courts him for hours and even days by following him with the corners of the mouth drawn back, cooing and trying to catch his eye. Among most primates, however, sex is a matter of seconds. He smacks his lips or flicks his tongue in and out, she presents or not, and then either it happens or it doesn’t. The male chimpanzees at Gombe, who form no pair bonds [unlike the hamadryas baboon], look at the receptive female from a distance of ten to twenty yards, sit so that their erection shows, and shake a little tree back and forth with one hand in a mild threat. She has to come to him. Evidently, courtship is perfunctory not only among the hamadryas, with their long-term marriages, but also in primate species in which the female has opportunities to choose another male instead.”
The following thoughts occur to me.
A failure to court is not tantamount to psychopathy. However, it is consistent with the lack of ‘caring and sharing’ that seems typical of primates. Again, I suppose that psychopathic men (approx. 1% of the males of the human species) are incapable of real courtship, although they probably can go through the motions well enough to fool some women. But my point is that courtship is about romance, and a psychopath cannot, I assume, feel romantic. Similarly, my point is that monkeys are incapable of romantic experiences as far as we can see, and in this corroborates their ‘quasi-psychopathy’ as I have sometimes been tempted to describe the syndrome.
I would also like to point out that, just as some human individuals are psychopathic and thus ‘monkey-like’, it is also easy to overlook that some or many human cultures lack courtship, or at least lack courtship before marriage (I cannot say for sure that courtship is absent in these cultures in romantic affairs, which often are extramarital). In many cultures, marriage is an arranged business in which the last thing on the man’s mind seems to be romance or courtship. Inasmuch as it is ‘normal’ or ‘typical’ for humans (outside the misleading and rather schmaltzy impression given by popular culture) to use the minimum of courtship prior to reproductive sex, our species is not that much different from most primates. Westerners may like to think that we belong to a species with ‘finer feelings’ and well-developed courtship, but this is questionable. Anyway it is easy to think of many other lineages of animals (including most birds) which have far better-developed courtship than humans, and genuine choice by the female (as opposed to coercion by the male and by family).
Rather than being the same thing, I see the quasi-psychopathy of monkeys as being a facet of the same syndrome of which the desultory courtship of monkeys is another facet.
Admittedly, canids (which seem to show so much more sympathy/caring-and-sharing than do monkeys) do not have elaborate courtship either. But my point is that the difference between monkeys and canids is that the social structure of the monkeys is so extraordinarily elaborate, and their sexual dimorphism so much greater than in canids, that it is reasonable to expect courtship in primates even if it is absent in canids. However, such does not seem to be the case.

Humans can be as venal as saintly. And some of the most egregious cruelty is committed by those who think they are being kind.

The bottom line seems to be that primates, in general, are remarkably ‘basic’ in their emotional lives despite their braininess, and the complicated interactions that are so conspicuous in their societies. 
Although we are a relatively romantic species, we also have a brutal, non-romantic side in some (many?) marriages and relationships. Is wife-beating only practised by psychopaths? As a species we are more caring than baboons, but I wonder if our extremes (e.g. wife-beating and wars) make us more brutal than baboons in many instances? It seems obvious that humans are more varied in behaviour than other animal species. This seems to be our niche - extreme variation from individual to individual, and culture to culture. It that enables us to form complex societies, including extroverts, introverts, artists, analysts, etc. This diversity makes for many different jobs and roles. But why the hell do we need to be so diverse along a continuum from brutal to caring within our own homes?

Is it possible that, whereas baboons are rather simply psychopathic/sociopathic by human standards, humans are actually POLARISED in the sense that we exhibit not only far more cognitive empathy but also far less cognitive empathy than even baboons.
Rwanda might illustrate this principle well. Who could doubt that if one visited virtually any of those families, a week before the killings stared in 1994, one would have been received with humility, gentleness, hospitality, generosity, and serenity? Yet those same people a week later were hacking each other to death, inflicting harm from which their society even now, decades later, has yet to heal?
So, it may be true that there is virtually nothing ‘saintly’ about baboons, and that in that way they fall short of us. But, on the other hand, there is nothing anywhere near as sociopathic about them as is manifest in our wars, our genocides, our sexual and child abuses, and our religious manias.

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Ingresado el 30 de junio de 2022 por milewski milewski | 0 comentarios | Deja un comentario

29 de junio de 2022

Largest mammalian predator over most of Australia was island- rather than continent-sized

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The largest-bodied indigenous mammalian predator over most of Australia, at the time of European arrival, is remarkably small by intercontinental standards.

I refer to the chuditch (Dasyurus geoffroii, https://www.inaturalist.org/taxa/40169-Dasyurus-geoffroii)

This species is remarkably small-bodied, it is mainly insectivorous, and it has remarkably large home ranges.

The body mass of Dasyurus geoffroii is about 1 kilogram in the adult female and 1.5 kilograms in the adult male. This is slightly larger than the meerkat (Suricata suricatta, body mass 0.7 kilograms), similar to the European polecat (Mustela putorius, body mass 0.7-1.5 kilograms), the Indian gray mongoose (Herpestes edwardsii, body mass 0.9-1.7 kilograms) and the Central American cacomistle (Bassariscus sumichrasti, body mass 1-1.5 kilograms), and smaller than the European pine marten (Martes martes, body mass about 1.5 kilograms) and the common genet (Genetta genetta, body mass about 2 kilograms).

The diet of D. geoffroii consists mainly of invertebrates although including vertebrates and fruits.

Furthermore, the chuditch has a surprisingly extensive home-range (about 400 hectares for the female and 900 hectares for the male) for such a small mammal. Reference for dispersal of dasyurus geoffroii, body mass about 1.5 kg, over at least 180 km as crow flies, from cape arid national park to salmon gums town: Morris et al. (2003) re Dasyurus geoffroii: https://books.google.com.au/books?hl=en&lr=&id=5IqhZoTEF10C&oi=fnd&pg=PA435&dq=dasyurus+geoffroii&ots=KNNA8cnXvq&sig=IMcD5Xvhb5b4rc1eE1-zKcRaHVs#v=onepage&q=dasyurus%20geoffroii&f=false

This suggests an extremely limited availability of prey on this nutrient-poor, fire-prone continent.
Distribution of Dasyurus geoffroii:

Dasyurus geoffroii, the largest extant native mammalian predator over most of Australia at the time of European arrival, has body mass ca 1 kg for adult female and ca 1.5 kg for adult male. This makes it smaller than a genet, although larger than a meerkat (suricate).
An idea of the body size of D. geoffroii can be got from this video clip: https://twitter.com/hashtag/chuditch
The following show the body size of D. geoffroii relative to the human figure for scale.
Dasyurus geoffroii with adult male human for scale, southwestern Australia (I think the photo is attributable to Ian Moone):


Dasyurus geoffroii:

Dasyurus geoffroii:

Dasyurus geoffroii (body mass about 1 kg), with adult female human for scale:
Dasyurus geoffroii with adult male human for scale, southwestern Australia (I think the photo is attributable to Ian Moone):

Dasyurus geoffroii:
Dasyurus geoffroii:

Suricata suricatta with adult male Homo sapiens:

Suricata suricatta with adult male Homo sapiens:
Suricata suricatta with adult male Homo sapiens:

Two points about Dasyurus geoffroii, the largest extant native mammalian predator found in southwestern Australia:
Firstly, this species is not about the same size as a domestic cat, as sometimes claimed. Instead, its body mass is only about 1 kg. That of the domestic cat is at least 3 kg, so in reality this marsupial is only about a quarter of the body mass of the average domestic cat.

To put this into a South African perspective, D. geoffroii is larger than a suricate but about half the mass of a genet. Both of the species of genets found in the vicinity of Cape Town are about double the body mass of D. geoffroii, because both have body mass about 2 kg (about half of the average domestic cat in Cape Town). In fact, the closest similarity in body mass can be found with the zorilla (Ictonyx striatus), often seen as road-kill in South Africa.

Yes, that small carnivore represents the largest extant native mammalian predator in the whole of southwestern Australia, an area larger than the whole of South Africa. I exclude the dingo because it seems that this canid was introduced only about five thousand years ago.
It is thoroughly remarkable what a limited capacity the natural ecosystem in southwestern Australia had to support mammalian carnivores. Extinct in the area (before European arrival) are Sarcophilus harrisii and Thylacinus cynocephalus, but even those carnivorous marsupials are only about jackal-size, not wolf-size.
What I learned during a talk by Dr Peter Mawson, who leads the captive breeding programme for D. geoffroii at Perth Zoo, is how vast the home ranges of this species are. The home range of males is about 1000 ha! A captive-bred individual released in Cape Arid National Park (just west of the Nullarbor) next turned up (healthy) in a chicken pen in Salmon Gums, which means that even if he moved in a straight line he walked at least 150 km! (probably closer to 200 km).

I would not have suspected that this rather dumpy little marsupial has such a wandering nature, and is so mobile. The species is largely terrestrial (less arboreal than, say, genets) although it can climb. But it does not have what I would call a cursorial body-form; in its limb proportions I find nothing to suggest particular adaptation to long-distance movement. So my interpretation of these enormous home-ranges is that the species is adapted to extreme sparsity of prey.
Please pause to think about this. It seems that the southwestern Australian environment had such a poor supply of prey that the largest fully indigenous mammalian predator is merely the size of a zorilla (a species so tiny that it manages to survive in the intensively farmed Swartland), and only about a quarter of the body mass of the average domestic cat. And even so, this marsupial has to range over vast areas to find enough food.
South African naturalists, can you imagine releasing a zorilla in Cape Town and finding it next in the Cederberg? I cannot find any information on home ranges in the zorilla, but it would not surprise me to find that this species usually spends its whole life on one farm.
Now comes an even more interesting aspect. Dasyurids have a tendency to live short lives and some species are downright semelparous. This syndrome is not particularly marked in D. geoffroii, but even this species has a lifespan of only about five years. It has a surprisingly short life, i.e. a remarkably limited longevity, for its body size. Even the domestic cat, which belongs to a short-lived group (Felidae) can live about 15 years. This short lifespan is unexpected for marsupials otherwise adapted to sparse food-supplies and an overall limited rate of reproduction and growth. To be clear: Dasyurus, although living such a short time, does NOT break the general marsupial rule of having limited rates of reproduction and growth relative to comparable placentals; it’s just that it uses a different life-history strategy to achieve these limited rates.
But my overall point is:
Although D. geoffroii is rather unremarkable in body form and dentition, coming over as a generalised animal compared to the more specialised-looking zorilla, genets, and mongooses of southern Africa, it is anything but generalised in its behaviour. It has the ability and proclivity to wander over an amazingly large area, and its lifespan is surprisingly short. I suspect that, among non-volant mammals, it has one of the greatest ratios of home range to lifespan ever recorded. I wonder if we could quantify that further?
For footage of a genet, showing body size relative to human size, see https://www.youtube.com/watch?v=nqowT5swY_A .
Dasyurus geoffroii (body mass about 1 kg and about the size of the road-killed zorilla you see while driving to the Cederberg):

Dasyurus geoffroii (body mass about 1 kg):
Salmon Gums is a town inside the pink area in the following map. An individual of D. geoffroii, released in Cape Arid National Park to the southeast (see it just west of Israelite Bay in the map below) walked all the way to Salmon Gums with no problem. This is about the distance from Cape Town to the Cederberg.
Dasyurus geoffroii (body mass about 1 kg), with adult female human for scale:

The largest extant native mammalian predator in an area as big as South Africa in southwestern Australia, pictured above, is only half the body mass shown below for genets.
Genetta sp., body mass about 2 kg:
Genetta genetta in Zululand:





(writing in progress)

Ingresado el 29 de junio de 2022 por milewski milewski | 1 comentario | Deja un comentario

The odd importance of primates in Madagascar

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One of the oddest features of mammalian biogeography is the prominence of primates in Madagascar. I’d like to explore this topic w.r.t. two aspects, namely a) body size, b) terrestriality, and c) comparison with the Americas.
The extant and extinct fauna of primates in Madagascar is bewilderingly diverse, so let me focus on one particularly noteworthy form, Archaeoindris. This, the largest of all lemurs (about the same size as gorillas), was among the largest primates ever to have evolved.
Large size suggests terrestriality in primates, but even some of the monkey-size lemurs were terrestrial, e.g. Hadropithecus (please see screenshot below).
Although primates are diverse in the Neotropics, and monkeys formerly occurred in the Antilles, there have never been large primates (body mass >25 kg) or terrestrial primates in the Americas. I suppose that this is because the niche of larger terrestrial omnivore was taken by Xenarthra there.
No extant monkey in the Americas is as terrestrial even as a vervet monkey (Chlorocebus). And there is nothing, extant or extinct, in the American primates anything like the baboons or geladas, or even the Asian macaques (which show a baboon-like trend towards large body size and terrestriality but do not take this trend to the extremes seen in Africa).
So it’s odd that both Africa and Madagascar, in their own ways, feature primates so prominently, with large and terrestrial primates playing prominent ecological roles. The Americas are quite different, because although primates have lived there since the time of the dinosaurs there has never been any evolution of terrestrial or large primates in North America, central America, South America, or the Antilles. For example, the Pampas was a paradise for grazers, but it never featured any mammal even vaguely like the geladas, those grazing large monkeys of Africa.
The niche of gelada (Africa) or giant/terrestrial lemur (Madagascar) seems to have been occupied in the Americas by sloths (Xenarthra) rather than by primates. This is not a case of particular evolutionary convergence because sloths are so different from monkeys and lemurs. For example, sloths have ever-growing teeth and use long claws; and whereas even primitive primates such as lemurs are above the mammalian average in braininess the sloths are below the mammalian average in braininess.
It’s well-known that Australasia lacked primates, having marsupials (e.g. possums) in vaguely similar niches to those of small primates. However, it’s less well-known that the Americas – despite their bewildering diversity of small monkeys today – have always lacked large or terrestrial primates, even in the times of the Pleistocene megafauna.
And Madagascar really is most peculiar, because not only is the extant fauna rich in primates but the extinct fauna was even richer – extending to extremely large species as well as probably terrestrial ones, most comparable to ground sloths.
Re Archaeoindris:
re terrestriality in Hadropithecus, which was not particularly large but foraged on graminoids and tubers:

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Ingresado el 29 de junio de 2022 por milewski milewski | 0 comentarios | Deja un comentario

Why have extreme canines evolved in Old World monkeys?

(writing in progress)
Old World monkeys (baboons, geladas, guenons, colobuses, langurs, macaques, mangabeys, talapoins, etc., https://en.wikipedia.org/wiki/Old_World_monkey.) show extreme specialisation of the canine teeth.

The mandrill (https://www.inaturalist.org/taxa/43533-Mandrillus-sphinx) is a particularly spectacular example (https://www.reddit.com/r/natureismetal/comments/lg5mn3/yawning_mandrill_showing_why_hes_not_to_be_fucked/ and https://www.shutterstock.com/video/clip-1024270445-mandrill-mandrillux-sphinx-yawning and https://www.shutterstock.com/video/clip-1024270421-mandrill-mandrillux-sphinx-yawning).

Note the extremely specialised lower premolar ‘whetting-stone’ for the upper canines, on the mandible (https://search.library.wisc.edu/digital/A4LMK3O4YAMOKG8V and https://www.etsy.com/au/listing/934210586/mandrill-baboon-monkey-skull-replica and https://carnefx.com/shop/mandrill-baboon-monkey-skull-replica/).

What are the reasons for this?
There are basically three different categories of function that could explain the evolution of the extreme canine dentition in Old World monkeys. These are

  • defence against predators,
  • the killing of prey, and
  • intraspecific sparring.

The extreme development of the canines in Old World monkeys makes little sense as the result of natural selective pressure for defence against predators. This is because the females lack the defence; the extremely developed canine dentition is restricted to adult males. There is no coherent logic whereby these defences would show such extreme sexual dimorphism if they were mainly an anti-predator adaptation.

This is not to deny that the canines might be used in deterring or fighting off attacks by Carnivora; it is just to point out that this cannot have been the main evolutionary reason, because any pressure strong enough to shape the males’ canines to such an extreme degree would, logically, also have acted on the females’ canines.
At this point, many readers may be thinking ‘everyone knows that in baboons and other Old World monkeys the adult males take on the role of defending the whole group from predators.’ However, does this sexual skew really make sense?
Moving on to the second possible function:
The extreme development of the canines makes little sense as the result of natural selective pressure for the monkeys’ own predatory habits.

Most monkeys do kill other animals for food, and in the case of baboons this extends to infant gazelles. However, most animals caught do not need to be killed immediately, and in fact monkeys usually eat their prey alive rather than attempting to kill it first. And the monkeys’ jaws and incisors are strong enough that the canines are not needed for butchering the carcases.

I have yet to hear, for example, of an adult male baboon butchering an impala neonate’s carcase by means of the shearing mechanism of the canines. Furthermore, females should be as keen to eat meat as the males are, and they lack specialised teeth for butchering, let alone cleanly killing the prey.
Put differently:
Given the predominant omnivory of monkeys, it makes little sense that these animals have canines rivalling or exceeding those of like-size Carnivora. And it makes even less sense that such canines should be restricted to the males, given that males seldom share their kills with females or juveniles.
Moving on to the third possible function:
Nobody doubts that baboons and other Old World monkeys do indeed use their extremely-developed canines in intraspecific rivalry among males. However, it is something different to assume that this has been the main evolutionary reason for the development of these teeth.

The good all-round naturalist Bill Hamilton III, who loved to work in the Okavango and elsewhere in Africa, and who studied the chacma baboon specifically, told me over the phone in 1989 (seven years before his death) that he had come to the conclusion that the evolution of canines in baboons was all about male-male rivalry. However, I did not record his explanation in my handwritten notes and I gather he never published this view with his reasons. So it remains just an opinion, albeit from a credible researcher.
Most mammals that have elaborate or extreme weaponry, restricted to males, use that weaponry not only to hurt rivals but also to fence/spar/practise. Most horn-like structures in ungulates are used to spar rather than to kill. In those cases where the horns really are purpose-built for impaling (as in e.g. rupicaprins and bushbucks), the skin in appropriate parts of the anatomy is correspondingly thickened into a kind of shield.

As far as I know, male baboons ‘spar’ with their teeth in an ambivalent way (deftly avoiding bites rather than clashing teeth). Although serious rivals do puncture, rip and impale each other’s faces and forequarters there is no thickened skin in these locations. Instead baboons seem simply to heal rapidly from their wounds.
But my main point w.r.t. to the evolution of such extremely dangerous weapons for mere rivalry is as follows.

It seems unnecessary for the weapons to be quite so murderous-looking, even if their main purpose is to show off macho. The males could be unarmed except in the sense of wrestling powerfully. There are various arrangements in the animal world for contests of the male hierarchy, and mating rights. The canines and their whetting-stone lower premolars seem like ‘overkill’ for mere rivalry among males, and I cannot see any advantage in having them so extremely designed that they really are among the most dangerous-looking weapons of any large mammal in the mammal communities in which baboons, in particular, reside.

Even if one argues that males somehow ‘need’ such extreme weaponry for their macho posturings, the associated risks for females should ensure some limitation by natural selection. It is serious enough that mature males of baboons are double the body mass of females, and throw their weight about in a hooliganish way. Adding such murderous weapons to the bluster seems excessive.
Could the explanation invoke a combination of all three factors? Possibly.
If readers remain unconvinced that there is anything anomalous about the extreme evolution of canine teeth in Old World monkeys, I can add particular observations in each of the categories I outlined above, namely defence against predators, the killing of prey, and intraspecific sparring:
In the case of defence against predators:
The island of Sulawesi is on the far side of Wallace’s Line, beyond the natural ranges of any felid or canid. So the seven spp. of macaques restricted to this island have relatively few predators, and could be expected to relax any anti-predators defences typical of congeners on the southeast Asian mainland. Instead, the crested macaque (Macaca nigra, https://www.inaturalist.org/taxa/43457-Macaca-nigra) at least, and probably all of the other six spp. as well, have extremely well-developed canines in males, as seen in photos of fang-baring expressions (http://www.shahrogersphotography.com/detail/29383.html and https://www.dreamstime.com/yawning-celebes-crested-macaque-macaca-nigra-tangkoko-national-park-north-sulawesi-indonesia-yawning-laughing-celebes-image103164247 and https://stock.adobe.com/images/the-celebes-crested-macaque-open-mouth-and-shows-his-fangs-crested-black-macaque-sulawesi-crested-macaque-or-the-black-ape-natural-habitat-sulawesi-island-indonesia/272647303).

This suggests that the development of the canines has little to do with anti-predation.
In the case of the killing of prey:
The gelada (Theropithecus gelada, https://www.inaturalist.org/taxa/43530-Theropithecus-gelada) coexists in places with domestic livestock, particularly the domestic goat (Capra hircus, https://www.shepherdsongfarm.com/our-cause/night-shelters-traditional-sheep-housing/ and https://www.alamy.com/white-goats-grazing-on-the-hillside-simien-mountains-national-park-ethiopia-image339228088.html?imageid=3B89A2FC-E557-4FF7-9123-F45D6414155B&p=266810&pn=1&searchId=e8f5d43729ed5f6426bfeb2a65c7a508&searchtype=0).

If the canines were for killing prey, this situation should be conducive to males of the gelada killing the goat at least occasionally. After all, the masculine canines of the gelada are as large as those of the leopard, and kept sharper. It should be possible for males of the gelada to pounce on an adult individual of the domestic goat and kill it outright for food. Given that the gelada eats mainly greens, this species could be expected to be particularly ‘meat-hungry’. However, I have not heard of any such use of the canines for predation in this monkey.
In the case of intraspecific sparring:
As I explained indirectly above, the usual pattern in most mammals and birds is for males of sexually dimorphic species to possess organs somewhere in a blurry zone between armament and ornament. At one end of the spectrum is e.g. the peacock’s tail, which is purely macho-ornamental because it cannot be used as a weapon. At the other end of the spectrum is e.g. the horns of bushbucks, which are purely macho-armamental because they are not ornamental but are designed functionally for stabbing.

In the case of the gelada, the male is certainly ornamented in having a cape of long hair and an emblazonment on its chest (https://www.facebook.com/earthunreal/photos/a.246085523008107/897297337886919/?type=3 and https://www.dreamstime.com/gelada-baboon-male-portrait-simien-mountains-national-park-north-ethiopia-gelada-baboon-male-simien-mountains-ethiopia-image156334611 and https://www.flickr.com/photos/lindadevolder/5400974286 and https://www.rockjumperbirding.com/the-geladas-of-ethiopia-by-adam-riley/).

So, it is easy to visualise a situation in which these adornments would be enough to signify macho, and any physical struggle would involve the sheer strength of the animal and the loudness of its calls, together perhaps with biting by means of the strong incisors. It is hard to see why the gelada ‘bothers’ to have such extreme canines as armaments for male rivalry as well – particularly because females of this species have the same ‘lip-flipping display’ (https://www.reddit.com/r/natureismetal/comments/atyems/male_gelada_baboon_giving_a_threat_display/ and https://pixels.com/featured/threat-display-of-a-male-gelada-baboon-tony-camacho.html?product=iphone-case-cover&phoneCaseType=iphonexs) of the front teeth regardless of the fact that their canines are short and unimpressive (https://imgur.com/gallery/NDKYv).

Perhaps a clue to the real reasons can be found in the show-off yawn of mature males - which is really a way of passively threatening all in view with their long, sharp canines. Many cercopithecid monkeys, including many macaques, perform this display. (There seems to be nothing analogous with the angry fang-baring so familiar in the wolf and the domestic dog in either baboons or the Japanese macaque.)

The Japanese macaque (Macaca fuscata, https://www.inaturalist.org/taxa/43458-Macaca-fuscata) is the only wild primate on this archipelago, and is a species familiar in many photos. What I have noticed is that this species differs to a surprising degree in its facial expressions from the chacma baboon (Papio ursinus, https://www.inaturalist.org/taxa/57556-Papio-ursinus).
The Japanese macaque is smaller than the chacma baboon; the adult female of the former is about half the body mass of the adult female of the latter. However, the two species are broadly similar in their mainly terrestrial habits and their occurrence at the extremes of the environmental range for wild primates (chacma baboon is the most southerly wild primate and Japanese macaque is the most northerly).
The following is recommended reading: http://www.livescience.com/1498-americans-japanese-read-faces-differently.html.
I have yet to find a single photo convincingly showing mature males of the Japanese macaque fang-baring in the way seen in males of baboons. There are a few photos on the Web of mature males of the Japanese macaque showing the canines, but all seem to be innocent cases of yawning in boredom and relaxation.
Even when males of the Japanese macaque do show the canines in an emotional way, this seems to be

  • associated with fear rather than anger, and
  • accompanied by a social vocalisation.

The main difference I have found between the two spp. of monkeys is that male baboons use the yawn assertively and confidently, as a passive threat, whereas males of the Japanese macaque do not seem to do so. This is consistent, to some degree, with the fact that neither body mass nor canine size is as extremely different from that of the female in this macaque as in baboons.
One possible evolutionary reason for this difference is that the Japanese macaque, being restricted to islands, had relatively little pressure from predators. An extremely odd biogeographical fact about the Japanese archipelago is that there was not a single species of felid on any of the larger islands, and this applies not only to big cats but even to small cats.
Papio ursinus adult male, sinister yawning as display of weaponry:
Papio ursinus adult female, innocent yawning in boredom:
Macaca fuscata, showing that sexual dimorphism is far less than in Papio ursinus:
Macaca fuscata, adult male yawning in boredom/relaxation:

Macaca fuscata, adult male yawning in boredom/relaxation:

Macaca fuscata, adult male yawning in boredom/relaxation:
Macaca fuscata, adult male yawning in boredom/relaxation:
Macaca fuscata, adult male opening mouth in what I interpret to be a fear-grimace, accompanied by the appropriate vocalisation (probably of appeasement or distress):
Macaca fuscata, ditto:
Macaca fuscata, ditto but in this case apparently an adolescent rather than mature male:

Macaca fuscata, ditto:

Macaca fuscata, ditto:

Macaca fuscata, showing once again the canines of the adult male but once again probably not an angry expression but rather a fearful or appeasing one, i.e. a fear-grimace:

Macaca fuscata, adult female yawning in boredom/relaxation:

Macaca fuscata, adult female fear-grimacing accompanied by appropriate vocalisation:

Macaca fuscata, ditto:

Macaca fuscata, ditto:

Macaca fuscata, ditto:

(writing in progress)

Ingresado el 29 de junio de 2022 por milewski milewski | 0 comentarios | Deja un comentario


(writing in progress)

Jaguarundi has the dullest yet most confusing colours of all cats

The jaguarundi1 is ostensibly among the plainest-coloured2 of all felids, but in a sense has the most complicated colouration of the 40 species in its family3. This is because this aberrant cat takes colour-polymorphism to extremes that are virtually impossible to summarise concisely in a zoological description such as that in a field-guide to Neotropical mammals. Not only are there several colour-morphs, but each morph has sub-morphs4, all possible in the same litter. Because the jaguarundi is found only as occasional individuals5 throughout its range, it follows that there must be few encounters in which this weasel-shaped felid is actually identified by either its prey or its own potential predators such as larger carnivores.

[for photos, see the many emails sent by Antoni to Anthony about 18 months before this time of writing, which is Feb. 2016 – AJM to scope emails]

Excess iron absorbed into living cell may as well be rusted in

Iron is an essential nutrient in all organisms, but is unique among required elements in that it cannot be efficiently excreted by any known organism. This has created a remarkable biological asymmetry in which there are various physiological mechanisms dedicated to the correction of deficiency in iron, but no known mechanism dedicated to the correction of excess of iron. Because iron is so reactive, any excess brings risks of oxidative stress6 and accelerated ageing. A possible reason for the inability or reluctance of any living cell to excrete iron is that the costs of quarantining this heavy metal on its way through excretory systems exceeds the costs of correcting any cellular damage inflicted on cells by their content of iron as long as this metal remains tethered to complex organic molecules7.

A ban on succulence in peas, mimosas and caesalps

Leguminous plants are extremely diverse worldwide, comprising three families8, x genera, y species, and many growth-forms from low herbaceous plants through lianas to tall trees. The form and texture of foliage is also extremely diverse, ranging from simple leaves to bipinnately compound leaves on the one hand and phyllodes9 on the other. However, leguminous plants are remarkably lacking in any succulent10 species, the closest being three heath-like relatives11 of rooibos tea12 in South Africa which have small but somewhat fleshy leaves.

[photos of Aspalathus capitata taken in Cape Point Reserve about 1999]

The paradoxical stink of a vital fatty acid

Butyric acid13, which gives butter14, parmesan cheese, kimchi, durian15 fruit and carob16 pod their characteristic aromas, is so valuable physiologically in small concentrations that functions like a human vitamin17. However, in greater concentrations its odour – familiar in vomit and Athlete’s foot18 – is repulsive enough to be used by many species as a deterrent or defence. Butyric acid is used by the wolverine in its anal glandular secretions, by caterpillars19 to deter predatory insects, by apiarists to control the honey bee20 during collection of honey, and by anti-abortion protesters as a stink-bomb. Furthermore, some of the butyric acid absorbed by the human body has ultimately been synthesised by clostridial bacteria, which are themselves ambivalent because they can cause botulism, gas gangrene and tetanus.

Growth-formula for the Dutch: lactose-digestion flipping from frugality to affluence

The Dutch, more than any other human population, have grown in body size22 over the last 150 years. Although the modern affluence in dairy products and the extreme incidence of lactose-tolerance in this country are well-known, these only explain the sudden transformation in body size if the original selective pressures are understood. Lactose-tolerance was originally associated not with peoples23 who consumed milk as a staple, but rather with those who relied on meagre but essential supplies of milk to survive the northern winter when all foods were so scarce that the growth of children was seasonally arrested and adult body size fell short of the genetic potential. By this logic there was an unprecedented release from these constraints when all foods became abundant, because the digestive system of the Dutch is able to exploit dairy products particularly efficiently.

Not until you see the blacks of their eyes

Most monkeys can read the direction of another’s gaze by watching the orientation of the whole face but not by watching the eyes themselves28 to discern sideways glances. The long-tailed macaque29 is one of the few wild30 mammals that resembles humans31 in being able to follow the eye movements of another by reading shifts in the sclera of the eyeball, which is more exposed on one side or the other of the iris when the eyeball swivels in its socket. However, this species32 of macaque has inverted the relationship between sclera and facial skin seen in humans: instead of having eye-whites, this monkey has eye-blacks owing to the combination of a black-pigmented sclera and extremely pale33 eyelids.

Baboons’ inhuman eyes save them from inhumane captivity

Pig-tailed macaques56, the closest counterparts for baboons in southeast Asia, are kept in private captivity57 more frequently than are baboons58 in Africa. This is partly because juveniles of pig-tailed macaques have eyes reminiscent of human eyes in expressiveness, whereas juveniles of baboons have eyes so inscrutable that they lack human appeal. The difference arises because pig-tailed macaques59 show their eye-whites in partial resemblance to humans, whereas baboons60 hide their eye-whites by means of a combination of tightness of the eyelids and shading by the brow-ridges61.

Largest mammalian predator over most of Australia fit for an island rather than a continent

The chuditch76, which was the largest indigenous mammalian predator over most of Australia at the time of European arrival, is remarkably small by intercontinental standards. This mainly insectivorous77 marsupial has a body mass78 slightly larger than that of the meerkat79, similar to those of the European polecat80, the Indian gray mongoose81 and the Central American cacomistle82, and smaller than those of the European pine marten83 and the common genet84. Furthermore, the chuditch has a surprisingly extensive home-range85 for such a small mammal, further suggesting an extremely limited availability of prey on this nutrient-poor, fire-prone continent.

Lizard tongue as baffle-organ

The conspicuous exposure of the blue tongue and pink gape by the shingleback lizard93, when confronted by the human species94, cannot be called a threat-display because the virtually toothless mouth is harmless and there is no plausible mimicry of any other animal. Nor can the peculiarly broad flanges of the tongue be explained by the unremarkable foodprocessing in this omnivorous large95 lizard. The adaptive value of the tongue96 – in combination with the camouflaged body armour and the resemblance between the resting head and the fatty tail – is to cause enough confusion to stall attack by a potential predator. Most of the tongue therefore deserves a new term: baffleorgan.

Fang-baring is bad manners in Japanese culture

The mature males of many species of Old World monkeys104, including most macaques105, fang-bare by yawning ostentatiously as opposed to merely from boredom or relaxation. Instead of being contagious, this exaggerated fang-baring yawn implicitly forbids emulation. An unexplained peculiarity of the Japanese macaque106 is that this species rarely if ever features the fang-baring yawn. This anomaly is particularly wellillustrated by comparison with the crested macaque107 of Sulawesi, because both species are restricted to islands at the far limits108 of the distribution of macaques.


MACACA NIGRA of Sulawesi:

The original lawn-gardeners in Kikuyuland

Kikuyu grass120, one of the most successful species of lawn grasses worldwide, originates in a surprisingly restricted habitat on the slopes of volcanic mountains in East Africa. The wild herbivores that mow121 its shoots and aerate its roots in its natural state are the giant forest hog122, the olive baboon123, and certain species of African root-rats124.

Good dental manners in urban macaques

Most species of Old World monkeys133 yawn assertively to display their weaponry of long, sharp canines. This fang-baring expression of mature males134 is directed both intraspecifically (to maintain a social hierarchy) and interspecifically (to deter potential predators). However, the rhesus macaque135 is a remarkable exception because it is one of the most widespread and populous species of monkeys in densely-populated136 southern and southeast Asia but has seldom been photographed yawning menacingly. Since this species is so closely associated with settlements137, it is possible that the ancestral fang-baring habit has been lost as part of a specieswide anthropogenic culture, effacing any expression which might antagonise humans on whose tolerance the rhesus macaque depends.

Japanese macaque as a lowbrow human

The Japanese macaque144 is a favourite photographic subject because its face seems almost human. In particular, the eyes are accentuated despite the fact that – as in the Caucasian race of the human species145 – the iris can be as pale as flesh-colour. However, the emphases differ: in the Japanese macaque it is the sclera146 immediately around the iris that is dark whereas in the Caucasian human it is the eyebrow that is dark. This difference is partly explained by body size and scaling principles. The human, having by far the larger face147, has the iris proportionately too small for direct accentuation, making a framing design more effective.

1 Puma yagouaroundi
2 lacking even the expected countershading
3 i.e. Felidae
4 For example, some individuals have a dorsal stripe; others (at least in the fawn morph, at least) have a pale chest; some individuals (at least in the darkest morph) have brown heads, paler than the dark brown body; etc.
5 i.e. population densities are everywhere small
6 i.e. damage by free radicals
7 e.g. ferritin and haemoglobin
8 Papilionaceae, Caesalpiniaceae and Mimosaceae
9 petioles (leaf-stalks) expanded into a leaf-like surface in place of true leaves
10 in the sense of xerophytic
11 namely Aspalathus capitata, A. subtingens and A. pinguis
12 Aspalathus linearis
13 C3H7COOH and its precursors
14 The words ‘butyric’ and ‘butter’ have the same linguistic root.
15 Durio
16 Ceratonia siliqua
17 see bio-insight....
18 tinea pedis
19 i.e. in the osmeterial secretion of the larvae of papilionid butterflies in reaction to attack by ants
20 Apis mellifera
21 Molecular formula of butyric acid: https://en.wikipedia.org/wiki/Butyric_acid#/media/File:Butyric_acid_flat_structure.png
22 The average height (1.8 metres in 2015) of male adults in the Netherlands increased by 20 centimetres from 1865 to 2015.
23 e.g. Maasai, who are generally lactose-intolerant despite being the most specialised pastoralists on Earth
24 http://i.dailymail.co.uk/i/pix/2014/10/29/1414546631846_wps_7_BMI_survey_jpg.jpg
25 http://www.businessinsider.com.au/body-measurements-of-average-american-man-2013-9?r=US&IR=T
26 http://www.businessinsider.com.au/body-measurements-of-average-american-man-2013-9?r=US&IR=T
27 http://www.randalolson.com/wp-content/uploads/historical-median-male-height.png
28 as is normal for Homo sapiens according to the ‘cooperative eye hypothesis
29 Macaca fascicularis
30 The domestic dog (Canis familiaris) has this ability, unlike wild members of the same family such as the wolf (Canis lupus).
31 Homo
32 Various other species of the same genus (Macaca) have unpigmented, whitish scleras similar to those in humans.
33 unlike several other members of the same genus (Macaca), which have dark facial skin
34 Macaca fascicularis: http://us.123rf.com/450wm/pzaxe/pzaxe1409/pzaxe140900063/31524646-monkey-feeds-her-cub-animals--mother-and-child-indonesia.jpg?ver=6
35 Macaca fascicularis: http://cache4.asset-cache.net/xt/508490625.jpg?v=1&g=fs1%7C0%7CIBF%7C90%7C625&s=1
36 Macaca fascicularis: http://us.123rf.com/450wm/f8grapher/f8grapher1402/f8grapher140200010/25953721-a-close-portrait-view-of-a-yellowish-golden-brown-to-gray-crab-eating-macaque-with-a-mustach-and-whi.jpg?ver=6
37 Macaca fascicularis: http://il8.picdn.net/shutterstock/videos/12519524/thumb/1.jpg?i10c=img.resize(height:160)
38 Macaca fascicularis: https://classconnection.s3.amazonaws.com/356/flashcards/1260356/jpg/cynomolgous_macaque-13E95EE89F24C9F254E.jpg
39 Macaca fascicularis: http://images.fineartamerica.com/images-medium-large/long-tailed-macaque-monkey-macaca-fascicularis-leanne-lei.jpg
40 Macaca fascicularis: http://cache3.asset-cache.net/gc/539659683-close-up-portrait-of-a-long-tailed-macaque-gettyimages.jpg?v=1&c=IWSAsset&k=2&d=nw3eX4QxwDnqRKlLmfw18cSKOtyk7k7WLYE5wF3lxi1J%2BKpKUOcWaSryNhy0IYHN
41 Macaca fascicularis: https://s-media-cache-ak0.pinimg.com/736x/98/b5/1b/98b51b369c7ad1e13ac96171fef232ee.jpg
42 Macaca fascicularis: http://www.rgbstock.com/cache1wuFXo/users/t/te/teslacoils/300/oA6MINW.jpg
43 Macaca fascicularis: http://previews.123rf.com/images/f8grapher/f8grapher1402/f8grapher140200011/25953303-A-close-portrait-view-of-a-yellowish-golden-brown-to-gray-crab-eating-macaque-staring-away-Also-know-Stock-Photo.jpg
44 Macaca fascicularis: https://www.elmwildlifetours.co.nz/images/dmImage/StandardImage/WEBmacque.jpg
45 Macaca fascicularis: https://pearlsofprofundity.files.wordpress.com/2013/09/monkey-business-2-frightened-mo.jpg
46 Macaca fascicularis: http://blog.targethealth.com/wp-content/uploads/2008/06/43.jpg
47 Macaca fascicularis: https://s-media-cache-ak0.pinimg.com/236x/48/ef/5b/48ef5b2e7c25017acbe1bbeeae778f0e.jpg
48 Macaca fascicularis: http://www.wildeyeview.com/blog/wp-content/uploads/2009/11/Long-Tailed-Macaque_0186-523x369.jpg
49 Macaca fascicularis: http://www.pumapix.com/wp-content/uploads/2013/08/IMG_91426.jpg
50 Macaca fascicularis: http://1.bp.blogspot.com/-rq_74639qKI/UjgrZNc9P7I/AAAAAAAAAXw/z4HV_x8rbR0/s1600/Long-tailed-Macaque.jpg
51 Macaca fascicularis: https://c2.staticflickr.com/6/5224/5679500659_54407483b3_b.jpg
52 Macaca fascicularis: http://www.cmzoo.org/palmoilkit/Photo%20Library/Indonesia%20&%20Malaysia%20Wildlife/Long%20Tailed%20Macaque%20Adult-TG.jpg
53 Macaca fascicularis: http://cache1.asset-cache.net/gc/175800573-face-of-a-sad-looking-macaque-monkey-gettyimages.jpg?v=1&c=IWSAsset&k=2&d=VuwW%2BimYontLJSUWEvY0GbfALWFRsuscvRAr8qrf0kUsqDF%2B5IFgzKkZxDtDtE1Fw1wGOsHXzlZwiA6%2F9qsu5MuVFNZzWYbgPNK226NJZpE%3D
54 Macaca fascicularis: https://s-media-cache-ak0.pinimg.com/236x/6e/c1/e2/6ec1e2c8f31e8d9c4e7d86233e523677.jpg
55 Macaca fascicularis: http://www.photomazza.com/IMG/427x578xjpg_Il_Macaca_fascicularis_e_una_scimmia_catarrina_c_Giuseppe_Mazza.jpg.pagespeed.ic.ThflVKlc7h.jpg
56 Macaca leonina and M. nemestrina
57 i.e. outside zoos and laboratories
58 Papio spp.
59 i.e. juveniles and adult females, with the human resemblance reduced in mature males
60 i.e. both sexes at all ages beyond infancy
61 together with dark pigmentation of the sclera in all species of baboons other than Papio hamadryas
62 Macaca leonina juvenile: https://upload.wikimedia.org/wikipedia/commons/0/0d/Northern_Pigtailed_macaque_at_Koh_Lanta_Yai_Monkey_School.JPG
63 Macaca leonina or M. nemestrina adult female: http://farm2.static.flickr.com/1153/1392202878_453b10daf3.jpg
64 Macaca leonina or M. nemestrina juvenile: http://oceans.wildiaries.com/system/pictures/0003/0029/Pig-tailed_Macaque_KR_290910_1.jpg
65 Macaca nemestrina juvenile: http://ngm.nationalgeographic.com/u/TvyamNb-BivtNwcoxtkc5xGBuGkIMh_nj4UJHQKuorjkbW9Rit2WGnGI6JAtBY9V2c5I5ODOKDydUQ/
66 Macaca nemestrina juvenile: http://ih1.redbubble.net/image.185584380.5153/flat,1000x1000,075,f.u1.jpg
67 Macaca nemestrina adult female: http://lh6.ggpht.com/7XmHb0cfvlCYDVp6CgNBhVZF1tSusqxqKOhtVhbpGE5KM0HUCApVjf15WJptG7wqIxM6_UFdylFCWKsPJSY=s580
68 Macaca leonina or M. nemestrina adult female.
69 Papio anubis juvenile: http://www.macleans.ca/wp-content/uploads/2013/04/Anup-Shah-baboon.png
70 Papio anubis? juvenile: http://senecaparkzoo.org/Content/upload/modules/galleries/31/148_36_large_baboon.jpg
71 Papio ursinus juvenile: http://s3.amazonaws.com/medias.photodeck.com/7b6f1d48-404d-4871-b949-c0d9c2aaaf87/Brett-Cole-South-Africa-00145_medium.jpg
72 Papio ursinus juvenile: http://www.photosbyangelika.com/wp-content/themes/photocrati-theme/galleries/post-131/Animal%20Picture%20close%20up%20young%20Baboon%20face%20Tokai%20Forest%20South%20Africa%20-%20IMG_8446.jpg
73 Papio ursinus? juvenile: http://usercontent1.hubimg.com/8271912_f520.jpg
74 Papio ursinus juvenile: http://www.ecotourism-namibia.com/typo3temp/pics/0eb2535dd4.jpg
75 Papio anubis juvenile: http://heathen-hub.com/HLAY_young_baboon_1000_IMGP1565.jpg
76 Dasyurus geoffroii
77 The diet consists mainly of invertebrates although including vertebrates and fruits.
78 The body mass of Dasyurus geoffroii is about 1 kilogram in the adult female and 1.5 kilograms in the adult male.
79 Suricata suricatta, body mass 0.7 kilograms
80 Mustela putorius, body mass 0.7–1.5 kilograms
81 Herpestes edwardsii, body mass 0.9–1.7 kilograms
82 Bassariscus sumichrasti, body mass 1–1.5 kilograms
83 Martes martes, body mass about 1.5 kilograms
84 Genetta genetta, body mass about 2 kilograms
85 about 400 hectares for the female and 900 hectares for the male
86 Distribution of Dasyurus geoffroii: http://www.environment.gov.au/system/files/resources/d6c37be6-42cd-48c4-9cb6-9919457c8898/files/dasyurus-geoffroii-2012.pdf
87 http://i9.photobucket.com/albums/a70/troutylow/ReadyReleaseChuditch.jpg
88 Dasyurus geoffroii: http://www.westernwildlife.com.au/Western_Wildlife/Chuditch_files/IMG_1866.jpg
89 Dasyurus geoffroii: https://pbs.twimg.com/media/Br6QFQrCIAQFAgb.jpg
90 Suricata suricatta with adult male Homo sapiens: http://i.dailymail.co.uk/i/pix/2012/04/09/article-2127209-1285B792000005DC-407_634x863.jpg
91 Suricata suricatta with adult male Homo sapiens: https://i.ytimg.com/vi/78mkyJCFzw/maxresdefault.jpg
92 Suricata suricatta with adult male Homo sapiens: http://blog.corbis.com/wp-content/uploads/2014/11/42-63039353.jpg
93 Tiliqua rugosa
94 Homo sapiens
95 body mass up to 0.9 kilograms
96 other than its tip, which is routinely used to sense the environment by frequent protrusion of the tip without opening the jaws
97 Tiliqua rugosa: http://bluetongueskinks.net/shingle13.jpg
98 Tiliqua rugosa: http://farm9.static.flickr.com/8451/8061111470_e8b8928246.jpg
99 Tiliqua rugosa: http://2.bp.blogspot.com/-r64I8txSFlA/T_P2k4OTUWI/AAAAAAAALIs/-u7ZQ073Dmc/s1600/4+Shingleback+4.jpg
100 Tiliqua rugosa: http://ih1.redbubble.net/image.5989431.4166/flat,1000x1000,075,f.jpg
101 Tiliqua rugosa: http://www.fotothing.com/photos/f34/f3411f20fd427da233a71bb0e166d136.jpg
102 Tiliqua rugosa: http://images.fotocommunity.de/bilder/australia/western-australia/bobtail-skink-1019726e-f7d0-4e24-86ba-0301da9845bb.jpg
103 Tiliqua rugosa: http://blog-imgs-30.fc2.com/n/y/a/nyandfulworld/P1030428.jpg
104 Cercopithecidae
105 i.e. species of Macaca
106 Macaca fuscata, which has been photographed particularly frequently owing to its combination of picturesque settings (such as thermal pools and deep snow) and a face with particular human appeal
107 Macaca nigra
108 The Japanese macaque is the most northerly non-human primate on Earth while the crested macaque occurs only on the far side of Wallace’s Line, the biogeographical limit of the typical Asian fauna.
109 Macaca fuscata mature male, yawning as opposed to fang-baring: https://toraninjapan.files.wordpress.com/2011/01/img_5447.jpg
110 Macaca fuscata mature male, yawning as opposed to fang-baring: http://www.discoverwildlife.com/sites/default/files/imagecache/800px_530px/gallery/JY13-9_800.jpg
111 Macaca nigra mature male, fang-baring: http://www.chesterzoo.org/~/media/islands%20images/sulawesi/c%20jrme%20micheletta%202small.jpg?la=en
112 Macaca nigra mature male, fang-baring: http://farm7.static.flickr.com/6148/6009068650_be0596cb6d_m.jpg
113 Macaca nigra mature male, fang-baring: http://ichef.bbci.co.uk/wwfeatures/624_351/images/live/p0/2p/4c/p02p4cln.jpg
114 Macaca nigra mature male, fang-baring: http://www.stevemetildi.com/galleries/142_Indonesia_2014/photos/crested_black_macaque_yawn_Q5Q2888_copy.jpg
115 Macaca nigra mature male, fang-baring: http://40.media.tumblr.com/62714c4ad2b966a6f914fbc3f5a32c61/tumblr_nhwaw38GHa1ta6h6to1_1280.jpg
116 Macaca nigra mature male, fang-baring: http://ichef.bbci.co.uk/wwfeatures/624_351/images/live/p0/2p/50/p02p50sl.jpg
117 Macaca nigra mature male, fang-baring: https://pbs.twimg.com/media/CJuRbSGWwAAXgQT.jpg
118 Macaca nigra mature male, fang-baring: http://www.shahrogersphotography.com/gallery/FeaturesStories/BlackcrestedMacaque/T11-98.jpg
119 Macaca nigra mature male, fang-baring: http://c8.alamy.com/comp/E4661T/celebes-black-crested-macaque-macaca-nigra-sub-adult-male-yawning-E4661T.jpg
120 Pennisetum clandestinum
121 The African buffalo (Syncerus caffer) is common throughout the natural habitat of kikuyu grass but is not responsible for maintaining this plant as a lawn because its large, blunt mouth is incapable of grazing short grass.
122 Hylochoerus meinertzhageni, which eats grass as a greater proportion of its diet than expected for a pig
123 Papio anubis, which is able to eat grass as a greater proportion of its diet than expected for a monkey, partly because it is one of the largest of monkeys
124 Tachyoryctes
125 Hylochoerus meinertzhageni: https://upload.wikimedia.org/wikipedia/commons/thumb/e/e6/Hylochoerus_meinertzhageni2.jpg/220px-Hylochoerus_meinertzhageni2.jpg
126 Hylochoerus meinertzhageni: https://upload.wikimedia.org/wikipedia/commons/thumb/3/3b/Hylochoerus_meinertzhageni.jpg/220px-Hylochoerus_meinertzhageni.jpg
127 Papio anubis: http://media-cdn.tripadvisor.com/media/photo-s/00/11/db/42/baboons-on-aberdares.jpg [photo is extremely apt as taken in the natural habitat of kikuyu grass in Aberdares National Park. Indeed at least some of the lawn in these photos probably consists of kikuyu grass in its natural state]
128 Papio anubis: http://www.africapoint.com/images/blogs/safari-wallpaper-baboon/A-Baboon-and-Her-Infant-Taken-at-Aberdare-National-Park_blog_image.jpg [photo is extremely apt as taken in the natural habitat of kikuyu grass in Aberdares National Park. Indeed at least some of the lawn in these photos probably consists of kikuyu grass in its natural state]
129 Tachyoryctes spendens: http://farm3.staticflickr.com/2645/4146574088_836d320881.jpg [photo by David Bygott, who has previously granted us permission]
130 Tachyoryctes splendens: http://www.biolib.cz/IMG/GAL/256410.jpg
131 Tachyoryctes splendens: http://www.planet-mammiferes.org/Photos/Rongeur/Myomo/AutMurid/TachSpl4.jpg
132 Tachyoryctes spendens: http://www.biolib.cz/IMG/GAL/256408.jpg
133 Cercopithecidae
134 The canine teeth of females are not long enough to be particularly dangerous in any species of Cercopithecidae.
135 Macaca mulatta
136 by Homo sapiens
137 The environment is no longer pristine any part of the range of the rhesus macaque.
138 Macaca mulatta adult male: http://www.skullsunlimited.com/userfiles/image/category5_species_6259_large_3.jpg
139 Macaca mulatta adult male: http://www.skullsunlimited.com/record_species.php?id=6259
140 Macaca mulatta adult male: http://www.skullsunlimited.com/record_species.php?id=6259
141 Macaca mulatta adult male: http://www.skullsunlimited.com/record_species.php?id=6259
142 Macaca mulatta adult male: https://boneclones.com/images/store-product/product-423-main-main-big-1432240234.jpg
143 Macaca mulatta adult male: http://cdn2.arkive.org/media/B5/B5D9F561-DA1F-42EC-BC26-9126B23A1D13/Presentation.Large/Male-rhesus-macaque.jpg
144 Macaca fuscata
145 Homo sapiens
146 The human eye shows far more of the whitish sclera than in any non-human primate; as in other Old World monkeys (Cercopithecidae), the Japanese macaque does not use pale tones to emphasise the eyes except in the form of the closed upper eyelid.
147 Average body mass of adult females is about 50 kilograms in the human species vs about 8 kilograms in the Japanese macaque.
148 Homo sapiens and Macaca fuscata: http://www.japanvisitor.com/images/content_images/macaque-6.jpg
149 Macaca fuscata: https://upload.wikimedia.org/wikipedia/commons/5/50/Wildlife_primate_monkey-of-japan_macaca-fuscata_closeup_31-05-2010.jpg  [Please note: photo of the Japanese macaque is freely available from Wikipedia]
150 Homo sapiens: http://goldenmeancalipers.com/wp-content/uploads/2011/12/mirror11.jpg
151 Homo sapiens: https://cdn2.vox-cdn.com/thumbor/
152 Macaca fuscata: https://upload.wikimedia.org/wikipedia/commons/f/fa/Macaca_fuscata_meditation.jpg [Please note: photo of the Japanese macaque is freely available from Wikipedia]
153 Homo sapiens: http://s3-ec.buzzfed.com/static/enhanced/web04/2012/4/26/10/enhanced-buzz-27424-1335452024-0.jpg
154 Macaca fuscata: https://upload.wikimedia.org/wikipedia/commons/6/61/Snow_Monkeys,_Nagano,_Japan.JPG [another freely available photo (Wikipedia) for this bio-insight]

(writing in progress)

Ingresado el 29 de junio de 2022 por milewski milewski | 0 comentarios | Deja un comentario

Why no land tortoises in Australia? part 1

(writing in progress)

Land tortoises are completely absent from Australia, despite occurring in Eurasia, Africa, and the Americas.

The ‘obvious’ reason for the lack of land tortoises in Australia and New Guinea is ‘Wallace’s Line’ = the sea barrier separating Australia and New Guinea from southeast Asia (https://en.wikipedia.org/wiki/Wallace_Line).
This is how I would refute this notion, stepwise.
Firstly, tortoises have in fact crossed Wallace’s Line, so long ago that there is a great radiation of several families, many genera and > 30 spp. here. However, all the Australian and New Guinean tortoises are restricted to freshwater, and remain amphibious.

The fact that no species has evolved to be fully terrestrial needs an ecological explanation. If it is true, as sometimes claimed, that the ancestors of the freshwater tortoises of Australia and New Guinea have been here since Gondwana times, then all the more time has been available for them to evolve into fully terrestrial species.
Secondly, there has long been a convergent lineage of land testudines in Australia and the western Pacific: the meiolaniids (https://en.wikipedia.org/wiki/Meiolaniidae).

These extinct large testudines (https://en.wikipedia.org/wiki/Turtle), which occurred only in a Gondwana-type distribution (not in the Old World), evolved separately from land tortoises but seem to have been terrestrial. They went extinct in the Pleistocene, as recently as a few thousand years ago in nearby New Caledonia. The question here is why these deeply Australian counterparts for land tortoises failed to survive – again suggesting an ecological, not accidental, explanation.
Thirdly, tortoises are known to have crossed Wallace’s Line during the Pleistocene in the form of southeast Asian box turtles, which are more terrestrial than the freshwater tortoises of Australia and New Guinea. This species (Cuora amboinensis, https://www.inaturalist.org/taxa/39893-Cuora-amboinensis) survives today in Timor (https://en.wikipedia.org/wiki/Timor), which is the last island of Wallacea (https://en.wikipedia.org/wiki/Wallacea) short of Australia.

Since box turtles have crossed several sea barriers to reach Timor, and are tolerant of submersion, there seems no reason why box turtles could not have crossed the remaining sea barrier to Australia.
Fourthly, land tortoises as strictly defined are known to have crossed Wallace’s Line during the Pleistocene in the form of Megalochelys (https://en.wikipedia.org/wiki/Megalochelys). This, the largest of the giant land tortoises of the world, formerly ranged from the southeast Asian mainland to Timor.

Since Megalochelys must, as in the case of the southeast Asian box turtle, have crossed several sea barriers to reach Timor, there seems no reason why this land tortoise could not have crossed the final strait to Australia. So Wallace’s Line is an unsatisfactory explanation, although there remains some legitimate doubt as to whether the Timor Sea proved too wide to cross.
Fifthly, land tortoises, as strictly defined, are also known to have crossed Wallace’s Line during the Pleistocene from Borneo (https://en.wikipedia.org/wiki/Borneo) to Sulawesi (https://en.wikipedia.org/wiki/Sulawesi) – where they coexisted with a cockatoo (Cacatua) and marsupials.

Although Sulawesi is far north of Australia, and separated from it by various Indonesian archipelagoes, the Sulawesi land tortoises again show that sea straits pose questionable barriers for large land tortoises.
Sixth, land tortoises are known to have crossed sea barriers far wider than the several hundred kilometres separating Wallacea (specifically Timor) from Australia. Farther west in the Indian Ocean, the Aldabra giant tortoise (https://www.inaturalist.org/taxa/539233-Aldabrachelys-gigantea) is known to have reached the Aldabra archipelago (https://en.wikipedia.org/wiki/Aldabra) at least three times from Madagascar (https://en.wikipedia.org/wiki/Madagascar). Indeed, one individual was recently documented to have floated/swam a minimum of 740 kilometres from Aldabra to the East African coast, where it washed up with barnacles covering its legs and sternum.

So, Wallace’s Line explains little, because the width of its sea barriers is less than that separating the Aldabra archipelago from East Africa, and similar to that separating the Aldabra archipelago from Madagascar.
Seventh, land tortoises are known to have crossed sea barriers to reach the Galapagos archipelago (https://en.wikipedia.org/wiki/Gal%C3%A1pagos_Islands), which has always been separated from South America by hundreds of kilometres.

Indeed, land tortoises reached South America in the first place from Africa by crossing the Atlantic Ocean at a time when that ocean was still relatively narrow, but wider than the sea barrier separating Wallacea from Australia and New Guinea in the Pleistocene. The arrival of land tortoises in the Galapagos archipelago actually required two consecutive crossings of wide seas, by two different ancestral land tortoises.

So, Wallace’s Line explains little, because its sea barriers are narrower than either the early Atlantic or the distance from the South American mainland to the Galapagos.
With seven different reasons to doubt its validity as a barrier to the arrival of land tortoises in Australia and New Guinea, what is left of any argument invoking ‘Wallace’s Line’?

to be continued in ...

(writing in progress)

Ingresado el 29 de junio de 2022 por milewski milewski | 1 comentario | Deja un comentario

Not just mammals but also insects are more productive of food for humans in southern Africa than in Australia

(writing in progress)

Australia is the only vegetated continent lacking any indigenous ungulate, and any herbivore larger than kangaroos.

One possible interpretation is that the Australian vegetation is capable of supporting mammalian herbivores, but herbivorous niches have been emptied by relatively recent extinctions plus isolation from sources of recruitment of new herbivorous taxa. The extinctions took place long before the arrival of Europeans and domestic livestock, but were possibly anthropogenic.

However, herbivorous insects indicate that the Australian environment is relatively unsuitable for herbivores in a fundamental way. The difference between Australia and other continents applies as much to rapidly breeding invertebrates – which are not vulnerable to anthropogenic extinction – as it does to mammals.

This suggests that the difference in herbivory is intrinsic to the quality of Australian plants as food. Caterpillars illustrate the point particularly well.

This is because large-bodied species of emperor moths are widespread in both Australia and southern Africa, yet it is only in Africa that saturniid caterpillars (https://en.wikipedia.org/wiki/Saturniidae) are eaten by indigenous people as a major dietary item. This suggests that caterpillars are more productive in southern Africa than in Australia.

Furthermore, this difference holds good even within plant categories shared between the continents. For example, the genus Syzygium supports a saturniid caterpillar eaten by African people. However, it does not support any analogous caterpillar in Australia.

Large-bodied, edible caterpillars of Saturniidae occur on certain African trees including Colophospermum mopane (https://www.inaturalist.org/taxa/428749-Colophospermum-mopane) and Burkea africana (https://www.inaturalist.org/taxa/340238-Burkea-africana).

It is remarkable that there are no counterparts in Australia, despite the fact that large saturniids do occur on that continent. I can find no record of aboriginal Australians eating saturniid caterpillars. This indicates that there is something more fundamental about the poverty of herbivory in Australia than previously acknowledged.

The insects give us a clue to the real differences, because edible saturniid caterpillars are as different in incidence on the two continents as herbivorous mammals, and there’s no chance that anthropogenic extermination can be to blame.

The saturniid moth Micragone cana, one of about ten saturniid caterpillars on Earth known to be eaten on a considerable scale by indigenous people, eats the foliage of S. cordatum.
Here we have a family of moths shared between the continents. And in the case of this taxon of food-plants, we have not only a family epitomising the Australian flora, but a genus actually shared between Australia and southern Africa: Syzygium.

Syzygium cordatum) is one of few myrtles (https://en.wikipedia.org/wiki/Myrtaceae) that have managed to live beyond fire-free rainforest in Africa. And yet, contrary to all expectations, it is the African syzygium, not the Australian ones, that are food of a saturniid moth so large, prolific and poorly-defended chemically that it is a significant source of food for indigenous humans.
Basquiniana seems to constitute proof, at two levels, of the fallacy of the ‘but they didn’t get here’ and ‘but they were here and people killed them off’ belief.

Firstly, the saturniid family is shared between continents and well-represented in Australia, so there is no biogeographical explanation of an accidental type to explain why it is in Africa and not Australia that this family is food, on a large scale, for humans.

Secondly, the fact that edible saturniids lives on a syzygium in Africa, but not on congeners in Australia, proves that this applies even to within-genus comparisons of food-plants between continents. Even within a genus of myrtles (the plant family most strongly associated with the historical accident that is Australia) the caterpillars are somehow able to be prolific in Africa rather than Australia.
Myrtaceae dominate in Australia, where they provide no caterpillar large enough, common enough, prolific enough, or chemically defenceless enough to constitute food for aboriginal humans. This could easily be seen as a historical accident, and if an ecological explanation is given it is likely to be that myrtles are by their nature poor food for herbivores including insects.

Seen within the context of Australia alone, the lack of edible saturniids here would not seem remarkable at all. However, the error in most people’s assumptions is exposed when we discover that even the few exceptional Myrtaceae that have managed to penetrate savannas in Africa are in fact suitable food for just such kinds of caterpillars: particularly Basquiniana cana. This species eats Syzygium cordatum (https://www.inaturalist.org/taxa/338719-Syzygium-cordatum). This genus of plants is shared with Australia, where - like eucalypts - it hosts no such edible insect.
What this means:

In Africa, even those taxa (e.g. myrtles) usually associated with poor soils and fire are somehow capable of producing noteworthy herbivores (at least insects). Syzygium cordatum is, after all, in the scheme of things a nutrient-poor plant typical of sandy soils and fire-prone savannas.

And this is corroborated by the fact that the two better-known food-plants of edible saturniid caterpillars in southern Africa, namely Colophospermum mopane and Burkea africana, are also regarded as rather poor plants from the point of view of herbivory, being fire-prone, chemically defended, associated with difficult soils (sodic in the case of C. mopane, oligotrophic in the case of B. africana), and shunned by mammalian herbivores - which prefer e.g. acacias.
The bottom line: trees regarded as poor food for mammalian herbivores are capable of supporting edible species of insects in Africa but not in Australia, something that cannot possibly be explained by any accident of history or any anthropogenic extermination. Instead, it’s clear that there’s something in terms of actual resources that causes the intercontinental difference in the success of herbivores, i.e. herbivores across the board regardless of whether they are megaherbivores or just insects.

So, one of the remarkable differences between Australia and southern Africa is that only southern Africa has edible lepidopteran foliage-eating caterpillars, harvested on a large scale for human consumption, on trees belonging to the Caesalpiniaceae such as mopane and Burkea africana.

Interpretation of this intercontinental difference is not a straightforward matter of Australia being nutrient-poorer than southern Africa, because mopane dominates on sodic soils and Burkea (although characteristically African-looking with its flattish crown) is typical of nutrient-poor soils.

What I did point out is that the plants eaten by these caterpillars, viz trees in the Caesalpiniaceae, are poorly represented in Australia. Certain members of the Caesalpiniaceae (e.g. Bauhinia, Erythrophleum) do occur in Australia but no extensive woodland in Australia is dominated by this family and Australia lacks endemic, dominant genera analogous with Brachystegia. The edible caterpillars seem to be associated with this floristic difference.
Here is a parallel case: edible stinkbugs found in Zimbabwe with no analogue in Australia. The species referred to is Encosternum delegorguei (Tessaratomidae, https://www.inaturalist.org/taxa/428764-Encosternum-delegorguei), which sucks the sap mainly of Combretum spp.
My point about this is twofold.
Firstly, just as in the case of lepidopterans, the family of insects involved occurs on both continents, but only in southern Africa does it include abundant, large, edible species harvested as food for humans. The correlation with the big game of Africa is obvious but not yet fully explained. It means that small herbivores do not compensate for the lack of large herbivores in Australia; instead both small and large herbivores are better-represented in southern Africa than in Australia.
Secondly, the food-plants of this edible stinkbug are, in a way, analogous with those of the edible caterpillars. Once again, the family Combretaceae is present in Australia, but the difference is that the genus Combretum, so common in Africa and dominating certain types of woodland, is absent from Australia with no analogue. And once again, there is some ambivalence in the nutrient status of the food plants of the edible insect because Combretum tends to be intermediate in its nutrient status, neither fully eutrophic nor fully oligotrophic.
I think there is a general pattern in this: across the board, invertebrates tend to parallel the big game in being larger/more abundant/more attractive as human food, in southern Africa than in Australia. The same thing applies of course to termites and locusts.


(writing in progress)

Ingresado el 29 de junio de 2022 por milewski milewski | 0 comentarios | Deja un comentario

28 de junio de 2022

Floating meadows in South Africa, with particular reference to behavioural inversions in the hippopotamus

@magdastlucia @ludwig_muller @prairie_rambler @bobwardell @beartracker @tonyrebelo @goosiaczek @danielatha @brothernorbert

Floating meadow (https://en.wikipedia.org/wiki/Floating_island) is an important vegetation type in Amazonia. One way to think of this vegetation is as a grassland rooted in water instead of being rooted in soil.

Naturalists may not realise that floating meadow occurs in South Africa. Because its occurrence in this country is associated with the hippopotamus (Hippopotamus amphibius), it is relevant to mention other aspects of the ecology of this megaherbivore in the same region.

My source is Tinley K L (1976, Ecology of Tongaland).

The floodplain of the Pongolo River (https://en.wikipedia.org/wiki/Pongola_River) extends from Ndumo Game Reserve (https://en.wikipedia.org/wiki/Ndumo_Game_Reserve) south to the dam on the same river (https://en.wikipedia.org/wiki/Pongolapoort_Dam).
Under ‘aquatic and marginal pan vegetation’, Tinley (1976) lists the following plant species.
Submerged aquatic plants include Ceratophyllum demersum (https://www.inaturalist.org/taxa/60997-Ceratophyllum-demersum), Najas 'interrupta', and Utricularia sp. (https://www.inaturalist.org/observations?place_id=any&taxon_id=57861&view=species)
Semi-emergent plants include Nymphaea capensis (https://en.wikipedia.org/wiki/Nymphaea_capensis and https://www.inaturalist.org/taxa/321501-Nymphaea-nouchali), N. lotus, Potamogeton crispus (https://www.inaturalist.org/taxa/78707-Potamogeton-crispus), P. schweinfurthii (only one location), Trapa natans (https://www.inaturalist.org/taxa/169900-Trapa-natans), Ludwigia stolonifera (https://www.inaturalist.org/taxa/439825-Ludwigia-stolonifera), and L. octovalvis
Floating aquatics: Pistia stratiotes (https://www.inaturalist.org/taxa/78589-Pistia-stratiotes)
Marginal pan vegetation: Dominant are iMbuku watergrass Echinochloa pyramidalis (https://www.inaturalist.org/taxa/208774-Echinochloa-pyramidalis) and Phragmites mauritianus (https://www.inaturalist.org/taxa/343087-Phragmites-mauritianus).

On the dried mud along the edges of the pans, where short sparse growths of Echinochloa spp. occur, the vegetation is mainly Cyperus fastigiatus (https://www.inaturalist.org/taxa/583237-Cyperus-fastigiatus), Cyperus spp. (Zulu ‘iMizi’, suggesting that these cypes are useful in some way), Sesbania sesban, and Gomphocarpus physocarpus (https://www.inaturalist.org/taxa/281273-Gomphocarpus-physocarpus).

Behind the water edge vegetation are stands of scattered or closely growing large trees, commonly Ficus sycomorus (https://www.inaturalist.org/taxa/340164-Ficus-sycomorus), Vachellia xanthophloea (https://www.inaturalist.org/taxa/348763-Vachellia-xanthophloea), Trichilia emetica (https://www.inaturalist.org/taxa/595643-Trichilia-emetica), Faidherbia albida (https://www.inaturalist.org/taxa/343039-Faidherbia-albida), and Kigelia africana (https://www.inaturalist.org/taxa/81491-Kigelia-africana).

The tall trees are interspersed with clumps of Grewia caffra (https://www.inaturalist.org/taxa/340279-Grewia-caffra), Mimosa pigra (https://www.inaturalist.org/taxa/47445-Mimosa-pigra), Ficus capreifolia (https://www.inaturalist.org/taxa/507292-Ficus-capreifolia), Sesbania sesban (https://www.inaturalist.org/taxa/168865-Sesbania-sesban), and Phyllanthus reticulatus (https://www.inaturalist.org/taxa/340305-Phyllanthus-reticulatus), with a varying width of grass, some 2-5 feet high, of iSwani, whatever that means.
Flood plain vegetation: The areas of the flood plain which have no open stretches of water are covered mainly by Echinochloa pyramidalis interspersed with reedbeds (Phragmites), and with scattered growths of Cyperus fastigiatus and other Cyperus species on the ‘green mat’ of Echinochloa. Small patches of tangles (Grewia and Ficus spp.) are to be found, usually growing adjacent to the growths of Sesbania sesban.
Tinley also describes the catena thus:

  • At the edge of the flood plain Vachellia xanthophloea is dominant, interspersed with Trichilia emetica and occasional large Ficus sycomorus.
  • In places reeds Phragmites mauritianus and Echinochloa pyramidalis grow to the edge of stands of the V. xanthophloea.
  • Between the V. xanthophloea and the reeds, there are clumps of Ficus capreifolia and Grewia caffra growing over small shrub-like growths of V. xanthophloea and F. sycomorus.
  • In other areas there are fairly wide mud flats (during winter) between V. xanthophloea and the pans. Many of these mud-flat areas are covered with water-grasses (whatever that means) and sedges Cyperus spp.
  • In some areas thorn-bush grows to the water’s edge, and in others pans are surrounded by Echinochloa pyramidalis and reeds.
  • The majority of pans have lilies Nymphaea sp. and other aquatic plants growing in and along the edges.
  • Where pans do not occur, wide sections of the flood plain are covered with E. pyramidalis, interspersed with reed beds.
  • The Pongolo river forest is dominantly of fig trees (F. sycomorus), throughout the river’s length (now largely chopped down).
  • In the quieter stretches of the Pongolo River, submerged aquatic plants are able to flourish.

My commentary:

Floating meadow suffers from a failure to recognise it as a vegetation type in Africa, and Tinley’s description is limited accordingly.

The main problem with his description is that he does not state the depth of water in which Echinochloa grows. I infer from elsewhere that it is deep enough, at least in places, for the hippopotamus to hide in, i.e. > 1 m deep. It is also unclear what Tinley means by Cyperus growing ‘on’ the mat of floating grasses; do the roots of these sedges fail to reach the ground?
My impression is that, during the dry season, one would never notice Echinochloa as anything special in the Pongolo River area. I certainly did not, during my visit to Ndumo in 2013. This grass is present during the dry season but can be overlooked as just another grass on the edges of pans. However, during the wet season Echinochloa grows widely on the inundated floodplain, floating on the surface (I am unsure if the roots actually float as well; I presume so). This, I infer, becomes seasonally the dominant grass in summer over most of the floodplain. As far as I can make out, it is ungrazed by any large mammal during this season, except occasionally by the hippopotamus (foraging while submerged and visible only by the movements of the floating mat of grass). Surely all of this is rather extraordinary?
It is well-known that the hippopotamus rests in the water. However, as Tinley knew when he was only 21 years old, it rests on land during the

An aspect clear in Tinley’s report is how important parasites, including large-bodied biting flies, are for the behaviour of the hippopotamus.

The hippopotamus must rest under cover by day, but not necessarily in water. "Leeches are common throughout the waters of the flood plain and are to be found on the animals in quantities". In winter, when no biting flies are active, the hippopotamus often rests in riparian fig forest.

This means that even vegetation types we would not associate with the hippo, such as dense Vachellia and sand forest (where there is neither standing water at any time of the year nor any significant grazing available) do provide resting sites for the hippopotamus. The megaherbivore is hard to observe because the animals are under cover of vegetation and, partly, the darkness of night.

It is well-known that the hippopotamus prefers short grass on dry land (including regeneration after fire). Tinley states: “Watching a hippo grazing one notices that all the grass is cropped with the lips, which cover the incisors completely. The upper lip does the cutting, as the head is nodded downward with each gathering. On close inspection of the lips, it is found that the entire fore-edge of the upper lip has a sharpish, hard ridge, serrated in parts. When out, it has the appearance of the hard callouses which form on the hands and feet of humans.”

However, a particular grass eaten by the hippopotamus at the edge of riparian forest is Setaria megaphylla (https://www.inaturalist.org/taxa/552642-Setaria-megaphylla), which is actually called ‘hippo grass’. It is interesting that, when the floodplain is flooded shallowly (including the zone of Setaria megaphylla), the hippopotamus does not graze on the shallowly submerged grass. ‘In many places they wander as much as six miles in search of suitable grazing.’ I also infer something else that is seldom explicitly stated: that domestic Bos taurus X indicus also avoids shallowly submerged pastures. One does not see this domestic bovine grazing with its muzzle in the water.

By the way, it is noteworthy that the hippopotamus forages on the tubers of Nymphaea. Baboons (Papio spp.) are more similar trophically to the hippopotamus than is usually realised, because these monkeys graze, eat the fruits of Kigelia, and also eat the tubers of Nymphaea (https://www.alamy.com/adult-male-chacma-baboon-papio-ursinus-eating-a-water-lily-tuber-kruger-image68361882.html and https://www.alamy.com/stock-photo-chacma-baboon-papio-ursinus-eating-waterlily-tubers-kruger-national-48783036.html and https://www.agefotostock.com/age/en/details-photo/chacma-baboon-papio-ursinus-eating-water-lily-tuber-kruger-natl-park-south-africa/NHP-NDE002115A and https://www.offset.com/photos/adult-male-chacma-baboon-papio-ursinus-eating-a-water-lily-tuber-92234 and https://www.dreamstime.com/stock-photo-baboon-eating-water-lily-river-image86193779 and https://www.afripics.com/image/detail/a-chacma-baboon-eating-water-lily-bulbs-retrieved-from-the-water).
Most interesting of all:
The hippopotamus grazes on floating meadows. Tinley (1976) is the only clear reference that I have found: “At Ntonto Pan a herd of 15 hippos live in both the open pan waters as well as in amongst the marsh area of the pan. This marsh area is covered with a ‘floating’ blanket of iMbuku grass [Echinochloa pyramidalis], interspersed here and there with bullrushes, Typha latifolia and other water grasses, Cyperus spp. Many of the animals cannot be seen, their presence being revealed by the occasional heaving of iMbuku grass into the air and continued loud munching noises. Flocks of cattle egrets, Bubulcus ibis wait tensely for such movements, which send insects scattering everywhere. Sometimes a hippo stands up out of the marsh with matted bunches of iMbuku grass hanging from it.”

Many naturalists may assume that the hippopotamus prefers to rest in the water and, if leaving the water to rest, ventures only on to the immediate banks, or trampled areas/sandbanks in reedbeds. However, this species is bothered by leeches, and most of the immature males are killed by mature males each winter when the water bodies are concentrated.

So there are incentives - including the coldness of the water on winter nights - for the hippopotamus to rest out of the water at some distance from the familiar concentrations of the species. As Tinley knew already in his early twenties, the hippopotamus (at least on the Pongolo floodplain) rests out of water whenever it can, to avoid its large parasites, and to avoid being killed by its own kind.

In the winter, it rests out of the water, both by day and by night (after grazing enough grass on the now drained floodplain to satiate itself), in riparian forest where the ground is dry and there is no grass in the first place. In the summer, it rests out of the water only by night because of the bits of large biting flies (including Glossina), and tends to do in vegetation types which most naturalists would assume never to be visited by this megaherbivore (e.g. thorn thickets and dense woodlands beyond the floodplain, which are never flooded and offer little grass at any season).

Complementing this refutation of the idea that ‘the hippo rests exclusively in or immediately adjacent to water’ is a refutation of the even more common assumption that the hippopotamus grazes only on land. In fact, it does sometimes

  • excavate the tubers of Nymphaea in shallow water, and
  • graze on floating meadow (Echinochloa, a genus shared with e.g. the far more extensive floating meadows of the Amazon, where grazed by the manatee).

Indeed, it seems possible that the hippopotamus acts, in part, as a counterpart for manatees (https://en.wikipedia.org/wiki/Manatee) elsewhere. Both animals graze floating meadow in the same way: immersed in water and approaching the grass from below by day, so that it can be heard foraging while invisible owing to the cover of the floating grass.

So, while the hippopotamus is in one sense more terrestrial/diurnal than many naturalists think, it may in another sense also be more aquatic/nocurnal than they think.

Can we picture these scenes on the Pongolo floodplain? In summer, the hippopotamus ‘grazes’ by day on floating meadow from below the grass (protected from its seasonal bane, the large biting flies), then moves right beyond the floodplain to rest under dense non-riparian woodland and thorn thicket by night.

The information for all of this was published by Tinley more half a century ago. However, I have found no mention of some of these behaviours in e.g. Smithers and Chimimba (2005, https://www.cambridge.org/core/books/mammals-of-the-southern-african-subregion/5C2E1D1A9BD464C8A0F3D5A550595AFA).

Ingresado el 28 de junio de 2022 por milewski milewski | 2 comentarios | Deja un comentario

Comparison of mule deer with greater kudu w.r.t. mouth markings and front-of-ear

(writing in progress)
In this Post, I present first a good portrait of mule deer, and then a series of comparative portraits of greater kudu (all females). I do this first for profile and then for full-frontal portraits.

The aim is to compare the mouth markings and the front-of-ear patterns.

The following is the best near-profile illustration I’ve found for the mule deer. Note that the front-of-ear (not particularly large in this individual) is oblong and has extensive fur in a pattern of white and dark. On the mouth, there is a dark ‘fang mark’ while the upper lip has a dark patch (the pale parts of the upper lip being relatively inconspicuous). There are no cheek spots. I think this is the Rocky Mountain mule deer (it’s certainly not the desert mule deer) and the location is ostensibly near Calgary in Alberta, Canada.

The following six photos of greater kudu show a consistent pattern. I’ll deal with the front-of-ear below but this is what I find for the mouth markings. Greater kudus have cheek spots, present in all individuals although there is individual variation in number, size, and shape of the spots. There is always one spot on the mandible, which means that this ventral-most spot would potentially move relative to the other spot/spots during chewing. In addition, the cheek spots would shift owing to cheek-bulge when the cudball appears in the mouth, and thus possibly function to accentuate the bulge of the cudball.

Greater kudus also differ categorically from mule deer in lacking a ‘fang mark’. The closest thing to this ‘fang mark’ in greater kudus is the small dark area at the gape itself. While both mule deer and greater kudus have white chins and white upper lips at the anterior-most position of the upper lips, the pattern of dark vs pale on the upper lip differs. Whereas the upper lip of mule deer is basically dark with a spot of white at the anterior-most position, the upper lip of greater kudus is basically white, accentuated to various degrees by a dark area posterior to this white. The border between this white and this dark is consistently crisp, whereas the cheek spots are relatively blurred. Female greater kudus also differ from female mule deer in possessing a slight mandibular dewlap, the anterior part of which is white.






This is a typical full-frontal portrait for mule deer. Once again, this is in Alberta, Canada, where I find the mule deer to have relatively small ears.                                                                                                                                                                                                               
What follows is nine comparative photos for greater kudu.

This species has been photographed in full-frontal portrait more than perhaps any other antelope, so we have excellent material to study here. Please note that, while both mule deer and greater kudus have white on upper lip, lower lip, and chin, the area of white on the front of the mouth is greater in greater kudu than in mule deer.

This is because in greater kudus the upper lip is more prominent and also more broadly white, the chin is proportionately larger than in mule deer, and the white dewlap can also be seen in full-frontal view. In the case of the front-of-ear pattern, an obvious difference is that much of the front-of-ear of greater kudus is bare, and the white ear-curtain is so much more prominent in greater kudus than in mule deer that it one of the most conspicuous parts of the whole body in female greater kudus.

Mule deer do have large ears but the markings on the front-of-ear are ambivalent, possibly functioning as disruptive colouration and not as a display. In both mule deer and greater kudus, the white of the ear curtain wraps on to the ear stalk.








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Ingresado el 28 de junio de 2022 por milewski milewski | 0 comentarios | Deja un comentario

Aspects of the natural history of Lycium

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Lycium (https://www.inaturalist.org/observations?taxon_id=58333), which belongs to the tomato family (Solanaceae, https://en.wikipedia.org/wiki/Solanaceae), is an interesting genus biogeographically.
Lyciums occur on all vegetated continents (https://en.wikipedia.org/wiki/Lycium#/media/File:Carte_lycium.jpg), but the Americas are particularly important.

There are many species in both North and South America, and if there is a real centre for the genus in terms of sheer number of species, it is southern South America, e.g. La Pampa (https://en.wikipedia.org/wiki/La_Pampa_Province), Patagonia (https://en.wikipedia.org/wiki/Patagonia), and perhaps the Monte (https://en.wikipedia.org/wiki/Monte_Desert) and the Chaco (https://en.wikipedia.org/wiki/Gran_Chaco).

South America also has the greatest adaptive diversity within the genus.

For example, the South American species include some with the typical orange berries and others with odd, two-seeded, non-succulent fruits of unknown dispersal mechanism. The genus thus conforms to the concept of 'plasticfruits' (see my Posts of...).

Even in North America, lyciums are remarkably widespread in the various dry biomes of the southwestern USA and Mexico, including coastal sage (https://en.wikipedia.org/wiki/Coastal_sage_scrub), sonoran (https://en.wikipedia.org/wiki/Sonoran_Desert) and mojave (https://en.wikipedia.org/wiki/Mojave_Desert) deserts, pinyon-juniper woodland (https://en.wikipedia.org/wiki/Pinyon%E2%80%93juniper_woodland), etc., as well as reaching to e.g. Florida.
Eurasia too has plenty of lyciums (indeed, the name Lycium itself hails from Anatolia). It is from a Chinese species that the well-known goji berries of health food shops hail (https://en.wikipedia.org/wiki/Goji). This species is broad-leafed, and not as xerophytic (https://en.wikipedia.org/wiki/Xerophyte) as most of the species of semi-arid Africa, North America, and South America.
Lycium reaches Australia. Here it is widespread, but in the form of only one indigenous species. So, Australia is the odd continent out in the sense that lyciums are minimally poorly differentiated here, and possibly a relatively recent arrival.
The flower form in this genus varies enough that some species are pollinated by hummingbirds, others by insects.
The fleshy fruits are eaten by both the North American phainopepla and the Australian mistletoebird (https://en.wikipedia.org/wiki/Mistletoebird), both of which are known mainly for their role in dispersing and sowing mistletoes (https://en.wikipedia.org/wiki/Mistletoe). So, there is a functional link between lyciums and mistletoes, despite the general lack of phylogenetic or ecological affinity in other respects. It would be interesting to study those lyciums prone to infestation by mistletoe.
The fleshy fruits of lyciums are generally edible to humans, at least in limited quantities. However, as is not surprising for the Solanaceae, there is some tendency towards toxicity. The fruits of some species may be toxic when unripe and at least one species has fruits which are toxic even when ripe.
The rodent Psammomys seems to eat the foliage of lyciums in North Africa, perhaps in parallel with Parotomys or other Otomys-related rodents in southern Africa. American packrats (Neotoma) are also associated with lyciums although I’m not sure if they eat the leaves. I get the impression that such herbivory as takes place on lycium foliage is more among monogastric animals (including equids and colies) than among ruminants. Lyciums play an ‘interstitial’ role, if you like, in landscapes dominated by ruminants and their forage plants.
All lyciums seem to have a large ratio of root to above-ground biomass, with extensive roots spreading up to 9 m from the base of the plant despite the modest size of the shrubs. All species also seem to be deciduous, in most cases drought-deciduous. Lyciums seem to have potential as ‘living fences’ i.e. spinescent hedges. I get the impression that some American species can form thickets, extensive enough to surprise South African botanists who are used to seeing lyciums only as scattered plants in the Karoo and Highveld, and who are used to discounting lyciums when it comes to the composition of our main thicket vegetation types such as spekboomveld.
In general, lyciums occur in environments free from fire. They are also generally eutrophic with a tolerance for base-rich and even saline soils. However, most species would not be called halophytes.

Biogeography of genus Lycium: http://www.weeds.org.au/WoNS/africanboxthorn/docs/Feasibility_of_biological_control_of_boxthorn_final.pdf

It is interesting that hummingbirds pollinate american lyciums: http://www.fs.fed.us/database/feis/plants/shrub/lycand/all.html.

Reading that the cultivated Chinese species Lycium barbarum lives only to a maximum of eight years, I was curious about the longevity of wild spp. of Lycium, which give the impression of being durable, gnarled, and long-lived in their semi-arid habitats.
The references excerpted below state that the wild spp. of Lycium in the semi-arid southwest of North America are quite long-lived, up to 90 years. So the cultivated Chinese species has either been selectively bred to be short-lived, or represents an ancestral species that is shorter-lived than more ‘typical’ congeners.
It’s also interesting to note that Lycium has shallow, wide-spreading roots, NOT deep roots. Deep roots in the Mojave Desert are associated with evergreens, and Lycium is drought-deciduous, using its wide-spreading roots not for evergreenness but for persistence through droughts in a dormant state.
I suspect that the various southern African spp. of Lycium (which are indeed drought-deciduous) are like their Mojave and Sonoran congeners: long-lived, shallow-rooted but with roots spreading up to 9 m from the base of the plant within 0.5 m of the ground surface.


Lycium barbarum of Eurasia does not necessarily have succulent leaves: http://en.wikipedia.org/wiki/Lycium_barbarum#mediaviewer/File:Lycium_barbarum_Flower_Closeup_Miguelturra_CampodeCalatrava.jpg

Leaves of lycium chinense hardly look succulent: http://en.wikipedia.org/wiki/Lycium_chinense#mediaviewer/File:Lycium_chinense_2.JPG

Another non-succulent lycium, this one from South America: http://photography-fotografias.blogspot.com.au/2012/08/fotos-frutos-photos-fruits-plants.html

Confirming that lycium australe of Australia is succulent:

Therenis a hint that the mountain zebra may have eaten lycium.
Although zebras are mainly grazers, they have some interesting habits when it comes to supplementary browsing. The following hints that Lycium may be among the plants browsed by equids on occasion. This is interesting because Lycium is strongly defended with stem spines for a plant that seems rather unattractive to most ruminants such as eland. I’ve long pondered the niche of lyciums w.r.t. herbivory, finding them rather incongruous. This the first indication that monogastrics may find this plant more palatable than ruminants do, and I speculate that the desert warthog may have dug up the roots of Lycium, which are extensive (they can reach up to 8m from the plant despite the modest size of the shrub, at least in the American spp.).

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Ingresado el 28 de junio de 2022 por milewski milewski | 0 comentarios | Deja un comentario
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