30 de junio de 2022

Is it baboons, rather than chimps, that really epitomise machiavellian intelligence?

@tonyrebelo @ludwig_muller @jeremygilmore @dejong @beartracker @davidbygott

(writing in progress)

Morality may have adaptive value. The well-known primatologist Frans de Waal (https://en.wikipedia.org/wiki/Frans_de_Waal) has made a career from exploring this in a series of about ten books. His angle, in part, is that apes evolved morality as an adaptive strategy. This line of evolution has produced our own, human, morality.
 
But a possibility missed by de Waal may be that morality and social complexity are different adaptive strategies. Overlapping, certainly, but not not necessarily concomitant.

In this Post I refer to 'baboons' as including not only Papio (https://en.wikipedia.org/wiki/Baboon), but also Theropithecus and Mandrillus (https://en.wikipedia.org/wiki/Mandrillus). See https://press.uchicago.edu/ucp/books/book/chicago/B/bo5387727.html and https://press.princeton.edu/books/hardcover/9780691628929/in-quest-of-the-sacred-baboon.

Are baboons ‘proto-apes’, in the sense that they are part of the same overall adaptive trend towards something human-like? Or do they represent a different direction of adaptation, socially complex but devoid of proto-morality?

Nobody doubts that apes such as chimps (https://en.wikipedia.org/wiki/Pan_(genus)) are, socially and morally, ‘proto-humans’. However, to assume that baboons are, in the same sense, ‘proto-chimps’ is – I suspect – a mistake made implicitly/subconsciously by primatologists.
 
Baboons may show a different adaptive strategy, emphasising social complexity without any trace of the moral principles that we humans so understandably assume to go with social complexity. These Old World monkeys may possibly have evolved a peculiarly amoral or non-empathic society.
 
There would be nothing surprising about the amorality or lack of cognitive empathy in baboons if they were not so complex and versatile socially. However, given that baboons are more – not less - socially complex than chimps, it is puzzling that they show negligible morality/cognitive empathy. De Waal may have assumed that any hint of morality in the behaviour of baboons reflects an incipient morality. By contrast, I suspect that it reflects a vestigial morality - in the sense that in baboons the social complexity and versatility have actually been developed to the preclusion of moral evolution.
 
Morality is based on the distinction between right and wrong, or good and bad. I hypothesise that baboons are peculiarly unable to discern right from wrong, or good from bad, considering how extremely social they are.
 
Imagine an individual baboon in its natural group. The group consists of hundreds of individuals (actually up to about 1000 in Theropithecus gelada, https://en.wikipedia.org/wiki/Gelada). This individual is so socially intelligent (by virtue of a brain comparable to that of an ape in its size relative to body size) that it can recognise hundreds of individuals, and can know and follow the status of scores, if not hundreds, of these.

In a group of the chacma baboon, there is evidence that each juvenile to adult individual knows and follows (in the sense of the status updates on Facebook) the status of up to about 100 other individuals. That is impressive even by human standards, and – as far as I know – beyond the capacities of apes, which live in small groups. The social structure of chimps is looser and more nebulous than that of baboons.

So, much time and energy goes into cognition in baboons, and this cognition is all about ‘who’s who in the zoo'. Baboons are, as it were, the inventors of the facebook concept, and it almost seems that their large brains (about fivefold more massive than those of kangaroos of equivalent body mass) are devoted mainly to this social busy-ness.

But our baboon individual – despite this proficiency in recognising and following its group-members – betrays in many small ways how poor it is in discerning right from wrong/good from bad. Students of the behaviour of baboons have found repeatedly how different the morality of baboons is from that espoused by humans.
 
For example:

  • no adult baboon ever plays, or shows any sense of humour, despite the extreme playfulness of pre-pubertal juveniles;
  • no baboon seems to perform any act that is unambiguously altruistic; acts of what we humans would recognise as kindness are scarce and ambivalent in baboons;
  • no individual baboon ever teaches another individual anything;
  • no individual baboon ever shares food with another individual, or for that matter gives it any object or material at all as an active ‘here, take this’ gift;
  • even the concept of courtship seems alien to baboons, the only such behaviour being ambivalent in the sense that males seem to have no ethic of generosity towards females of the species; what seem, at first glance, to be ‘special friendships’ between male and female usually turn out, on closer examination, to have ulterior motives (e.g. the male is probably the father of the last offspring of the female in question, so has a stake in protecting this offspring simply in terms of reproductive success, something for which no element of morality needs to be invoked).

So, while de Waal and others may have assumed that baboons have a primitive morality, I suspect that what they may have instead is a ‘specially adapted amorality’. Whereas humans may be specialised as ‘the most moral of the primates’, baboons may be specialised as ‘the most amoral of the primates’. It may be misleading that the two lineages both show great social complexity and versatility.
 
Humans know right from wrong/good from bad, even if we fail our own standards. Baboons seem to emulate our political consciousness. However, there are extremely few individuals among baboons who act as if they know right from wrong/good from bad. The result is that baboons have societies that appeal to our humanity profoundly in the sense of mirroring so many layers and levels of what we recognise as family, society, and politics – but without reflecting the morality that we intuitively expect as part of this degree of sociality.
 
Frans de Waal (1982), in his book ‘Chimpanzee Politics’ (https://www.press.jhu.edu/books/title/9383/chimpanzee-politics#:~:text=The%20first%20edition%20of%20Frans,basic%20human%20needs%20and%20behaviors. and https://www.goodreads.com/book/show/389530.Chimpanzee_Politics), coined the term ‘machiavellian intelligence’ (https://en.wikipedia.org/wiki/Machiavellian_intelligence). The dictionary definition (https://www.merriam-webster.com/dictionary/Machiavellian) of the word ‘machiavellian’ implies amorality and a lack of empathy.
 
However, de Waal may have overlooked the possibility that, partly machiavellian though chimps undoubtedly are, baboons are more machiavellian. I suspect that de Waal did not fully realise that machiavellian intelligence is by definition amoral or non-empathetic intelligence.
 
The idea, that baboons are surprisingly amoral and non-empathetic relative to their great social complexity and versatility, is not necessarily new. Frans de Waal realised what machiavellian intelligence is, 40 years ago. What may be new is my idea that it is not chimps but baboons that epitomise machiavellian intelligence.

Chimps have machiavellian intelligence as an element of their psyche (more so than in humans, perhaps). However, baboons are the ones that epitomise this kind of intelligence, and which deserve to be used to illustrate it in its purest form within the Primates (the spotted hyena, Crocuta crocuta, possibly rivals baboons in this kind of intelligence within the Carnivora).
 
Did Frans de Waal possibly fail to realise that baboons are not just ‘proto-apes’, but forms of primates that specialise in machiavellian intelligence?

(writing in progress)

Anotado en 30 de junio de 2022 a las 05:25 PM por milewski milewski | 0 comentarios | Deja un comentario

Differences in facial expression between wolf and domestic dog

An important difference between the wolf (Canis lupus) and the domestic dog (Canis familiaris) is the appearance of the eyes in a direct look at humans.

In the wolf, the eyes are stark, i.e. they stare with an  ‘in your face’ colouration pattern, i.e. aggressive/dominant/assertive.

By contrast, in the domestic dog, the look is softer and more receptive, because there is not the same dark/pale contrast between the eye and the rest of the face. For example, in an otherwise rather wolf-like breed, the German shepherd, the eyes are less conspicuous than in the wolf because

  • the iris is not pale and therefore does not contrast with the dark eyelids, and
  • the pelage around the eyes is not pale.

(The dingo is intermediate, something that I’ve never seen pointed out about the dingo.)
  
Look at a wolf, and one sees something ‘inhuman’ and ‘beyond pity’. The appeal is only the thrill that such savagery can somehow persist in the far corners of today’s tame world. By contrast, look at a wolf-like domestic dog, and you see a ‘human’ face, full of pathos, empathy, and appeal.
 
I have chosen the two photos below to present this contrast succinctly.
 
The following portrait of the wolf is typical.
Canis lupus adult:
http://i.huffpost.com/gen/1156449/images/o-WOLF-facebook.jpg

The eyes stare starkly (balefully) because of the dark/pale contrast between iris and eyelids, and the further contrast between the whole eye and the pale face. The whole effect is somewhat counterintuitive, because if I stated that the wolf had both a pale iris and a pale face, one would not really expect the eyes to be particularly conspicuous. But the reality – partly owing to the dark eyelids – is that the eyes do stare conspicuously.

The wolf is taken to be the direct and sole ancestor of the domestic dog. However, photos of the 800 breeds of the domestic dog show that there is virtually no breed possessing this stark stare of the wolf. I suspect that this is partly because an extinct species other than Canis lupus is the real main ancestor of the domestic dog, with variable contribution from C. lupus in certain breeds. I accept that the stare has been selectively bred out of the wolf to produce an animal more empathetic and communicative with its human associates.
 
Many readers may find something wolf-like about the German shepherd.
Canis familiaris adult, German shepherd breed:
http://thumbs.dreamstime.com/z/german-shepherd-closeup-771297.jpg

However, the pattern of the face, with particular respect to the eyes, is quite different. The iris is now dark and so is the face. Because the eyelids remain in their original dark condition, all dark/pale contrast about the eyes is eliminated. The dog can look straight at the human now, without any impression of staring. As I will show in another Post soon, the dark muzzle of the German shepherd is actually a puppy-face in the ancestral species, which has been fixed in the domestic dog in a process akin to neoteny.

The closest thing in the wolf to this kind of face is that of the infant wolf at the stage just after its eyes have opened for the first time, a stage at which of course there is nothing but dependence and no hint of aggression or dominance. In many breeds of the domestic dog, the medial eye-whites will also show to some extent in a direct look such as we see in this photo. Such displays of the eye-whites are minimal in the adult wolf, and this is another element of similarity to humans that has been inadvertently bred into the domestic dog, and even into the dingo to some degree.

A further point to note is that the ‘eyebrows’ have been accentuated in the domestic dog compared to the wolf, further elaborating the empathetic facial expressions of the domestic dog.

At first glance there may seem to be little difference between the wolf Canis lupus (left, below) and the husky dog Canis familiaris (right, below).
 Canis lupus adult (left); Canis familiaris adult (right):
http://www.crazynauka.pl/wp-content/uploads/2013/01/tumblr_mh8svukENw1rafcg9o1_1280.jpg

However, in the wolf the eye language among adults is simple: an on-or-off stare. A stare is dominant and aggressive, and the alternative is simply to look away. The colouration of the eyes of the wolf, as explained by Ueda et al. (2014), accentuates this effect. The iris is pale and the eyelids and corner of the eye are dark, creating a stark-enough effect in terms of a stare. In addition, I have noticed something that Ueda et al. (2014) possibly did not notice, that the iris-edge in the wolf is dark too, in a way that is imperceptible in the stare but which helps to exclude any eye-white-display.
 
In the domestic dog, the pale iris of this breed (husky) may not be the same paleness as in the wolf. Instead, it may represent the infant of the wolf (https://www.companionanimalpsychology.com/2015/01/do-hand-reared-wolves-get-attached-to.html), in line with various other ways in which the domestic dog is infantilised relative to the wolf. Furthermore, in its interactions with humans (i.e. interspecifically rather than intraspecifically), the domestic dog does use its eye-whites (to varying extents depending on the breed) to produce facial expressions. These expressions are qualitative in contrast to the ‘quantitative’ (on/off) stare: they convey nuances of meaning along the lines of an ‘eye language’ to which humans can relate, even if the wolf cannot. And, probably overlooked by Ueda et al. (2014), the edge of the iris in the pale-eyed breeds/individuals of the domestic dog is not dark – although this difference is hard to spot in the photo-pair below.
 
There are also other, surprisingly large, differences between C. lupus and C. familiaris in their eyes and vision. The wolf has a horizontal streak in its retina, useful for scanning the horizon for movement. Depending on the breed of dog, this streak has been inadvertently reduced by selective breeding in C. familiaris, making the visual system somewhat more similar to that of the human in emphasising binocular vision and an ability to concentrate on an object in front of the animal.
 
So the bottom line is that, despite the apparent similarity shown in this photo-pair, the eyes and vision of C. lupus (putative ancestor of the domestic dog) and C. familiaris are more different than one might expect in two species that can still interbreed freely. In a sense, the domestic dog is a ‘human-eyed wolf’. Canis familiaris is deeply, not superficially, domesticated, as revealed by the details of its eyes and vision.

Anotado en 30 de junio de 2022 a las 09:11 AM por milewski milewski | 1 comentario | Deja un comentario

Differences among wolf, dhole, and African hunting dog in emphasis of stare

@tonyrebelo @jeremygilmore @davidbygott @maxallen @beartracker @douglasriverside @ludwig_muller

The wolf (Canis lupus), the dhole (Cuon alpinus), and the African hunting dog (Lycaon pictus) are approximate ecological equivalents in different regions. All are gregarious predators of ungulates, forage in a typically canid way, and have complex social organisation.

These belong to three different genera. However, one might think that the appearance of the eyes – so important in intraspecific communication – would be similar regardless of the various details of their generic differences.
 
The surprise is that the three species differ radically in the conspicuousness of their eyes, something that has never been explained.
 
As readers can see in the photos at the end of this Post,

Why would such a basic form of communication differ so much among apparently analogous animals all belonging to a single family?
 
Here are some clues.
 
I notice an inverse relationship w.r.t. the ear pinnae, as explained below.

Where the eyes are hidden, the ear pinnae stand out particularly clearly. This suggests that the African hunting dog in particular ‘stares with its ears’ (https://www.alamy.com/close-up-portrait-of-an-african-wild-dog-or-painted-wolf-lycaon-pictus-in-mana-pools-national-in-the-zambezi-valley-zimbabwe-endangered-species-image387700136.html and https://www.agefotostock.com/age/en/details-photo/african-wild-dog-lycaon-pictus-adult-close-up-of-head-resting-on-sandy-grass-area-okavango-delta-botswana/FHR-10354-00389-827).
 
The social hierarchy is strongly enforced in the wolf (partly owing to seasonal breakup and reuniting of the group), and less so in the dhole and African hunting dog.

In the African hunting dog it is males that stay in the natal group, whereas in the wolf it is females. To my mind, the role of males in Lycaon, as reproductive helpers, shows that they are even more altruistic than is true for the wolf. Does this help to explain their lesser need to keep using facial expressions to assert their authority?

Unlike the situation in the wolf, the hierarchies are separate for male and female in the African hunting dog (https://en.wikipedia.org/wiki/African_wild_dog).

In the case of the dhole, there seems to be an intermediate situation (https://en.wikipedia.org/wiki/Dhole): the species, relative to the wolf

  • is less territorial,
  • has less seasonally variable habitats,
  • has a less strictly-enforced social hierarchy, and
  • has less marked submissive behaviour.

There is already an inkling of these differences in the literature, but what is new here is this:
There seems to a gradation in substitution by the ear pinnae. Cocked ears are somewhat assertive, but less so than staring eyes owing to the more vague directionality of the ears. An 'ear-stare' is more polite than an eye-stare, hypothetically suiting the more altruistic species.
 
In summary:
 
Wolf, dhole and African hunting dog differ in facial expressiveness despite being gregarious predators with complex cooperation in foraging and reproduction. This is because the social hierarchy is most strictly enforced and renewed in the wolf, whereas assertive vs submissive behaviour is less expressed in the African hunting dog.
 
The new understanding I offer here:

The conspicuousness of the eyes and ears in wolf, dhole and African hunting dog vary inversely, in keeping with the general expressiveness of the face in these species with varying levels of enforcement of a social hierarchy.

In the wolf, the stare is emphasised by the pale iris and dark eyelids (https://www.istockphoto.com/photo/wolf-portrait-gm588348958-101010441?phrase=wolf%20staring and https://www.istockphoto.com/photo/staring-wolf-gm1270419883-373373499?phrase=wolf%20eye%20close%20up).

In the African hunting dog the eyes are masked but the ears are conspicuous instead.

The dhole is intermediate.
 
ILLUSTRATIONS

In the wolf, the eyes stand out from the face because the iris is pale enough, and the eyelids dark enough, to provide tonal contrast against the rather nondescript background of the face.
 
Canis lupus adult:

http://thumbs.dreamstime.com/x/timber-wolf-portrait-9065736.jpg

https://www.canstockphoto.com/wolf-1858057.html

https://www.gettyimages.com.au/detail/photo/gorgeous-gray-wolf-posing-against-lush-foliage-royalty-free-image/1302734679?adppopup=true

https://www.gettyimages.com.au/detail/photo/gray-wolf-eyes-royalty-free-image/1372772768?adppopup=true

In the dhole, the eyes are not accentuated by tonal contrast, so that there is no emphasis of the stare whatsoever. Instead, if there is any aspect of the face that is instantly noticeable, it is the ears, which possess conspicuously pale ear-feathers.

Cuon alpinus adult:

https://www.flickr.com/photos/john_kuk/2543678348

http://img12.deviantart.net/7a87/i/2014/100/a/d/the_red_dhole_by_picturebypali-d7dvyov.jpg

https://www.activewild.com/dhole/

https://www.alamy.com/stock-photo-wild-dog-or-dhole-cuon-alpinus-18098618.html?imageid=13CD4D30-DAAB-459F-8A6E-5A9CD534DD72&p=143230&pn=1&searchId=82f8b24b994b3a716b7ae79f6f2bf1d9&searchtype=0

https://www.alamy.com/asiatic-wild-dogdhole-cuon-alpinus-from-central-indian-forest-image451161108.html?imageid=E8133FEF-A4DA-4401-9AB9-A277100C81E1&p=660193&pn=1&searchId=82f8b24b994b3a716b7ae79f6f2bf1d9&searchtype=0

https://www.alamy.com/stock-photo-adult-indian-wild-dog-or-dhole-cuon-alpinus-also-known-as-the-asiatic-133875241.html?imageid=50515504-0DA5-4E87-8BC3-697F7F5C3531&p=11411&pn=1&searchId=82f8b24b994b3a716b7ae79f6f2bf1d9&searchtype=0

https://www.alamy.com/stock-image-dhole-or-asiatic-wild-dog-166396295.html?imageid=6FF471E9-C95C-4978-B09C-F233A80F9018&p=68495&pn=1&searchId=82f8b24b994b3a716b7ae79f6f2bf1d9&searchtype=0
 
Finally, in the African hunting dog, the eyes are actually masked. This could hardly be more different from the wolf, because not only is there no dark/pale contrast between iris and eyelids, but the iris is so dark that it is hidden in the dark fur surrounding the eye. Although the ears are not adorned, they are so large and dark that they dominate the countenance, emphasised by their dark/pale contrast with the forehead/temples.
 
Lycaon pictus adult:

https://www.mindenpictures.com/stock-photo-african-wild-dog-lycaon-pictus-portrait-south-africa-naturephotography-image90163062.html

https://www.masterfile.com/image/en/649-07585118/wild-dog-lycaon-pictus-mana-pools-national-park-zimbabwe

https://www.masterfile.com/image/en/400-03934175/portrait-of-an-african-wild-dog-or-painted-hunting-dog-lycaon

https://www.masterfile.com/image/en/600-08973286/portrait-of-a-wild-dog-lycaon-pictus-looking-at-the-camera-after

https://www.mindenpictures.com/stock-photo-wild-dog-resting-lycaon-pictus-savuti-channel-linyanti-region-naturephotography-image90157377.html

Anotado en 30 de junio de 2022 a las 07:06 AM por milewski milewski | 3 comentarios | Deja un comentario

Braininess in primates and other mammals, relevant to cognitive empathy and play behaviour

(writing in progress)

In recent Posts, I have pointed out that baboons and other primates have surprisingly little cognitive empathy for animals with such large brains.

So, it may be worth quantifying just how large the brains of baboons really are. The same applies to other relevant animals that are capable of play behaviour during adulthood.
 
Encephalisation Quotient (EQ) is a quantitative expression of brain mass/volume relative to body mass, corrected allometrically. It provides the most basic parameter of braininess.

EQ can only really be compared within lineages, because the brains of e.g. birds vs mammals are too different to make their EQ values comparable. Although the concept of EQ is mathematically simple, it is inevitable that various authors vary in how they calculate it, leading to quite large differences in the actual values among studies. The important thing is to make comparisons within a given study.
 
Some of the stand-out facts that emerge below:
 
Gibbons are much brainier than baboons despite being incomparably less social.
 
Capuchin monkeys (South America) are brainier than any ape (something that is often overlooked partly owing to the small body size of capuchins).
 
Baboons are by no means the brainiest of the Old World monkeys, being inferior to less gregarious genera such as Cercocebus (mangabeys) and Erythrocebus (patas monkey) in EQ.
 
The patas monkey in particular shows noteworthy braininess, consistent with its exceptional ability to survive, much as humans do, by its wits out in the open in a predator-ridden environment. The contrast between the patas monkey and e.g. the Bornean proboscis monkey, in braininess, is particular food for thought.
 
According to one study:
 
Homo sapiens has EQ of 7.4-7.8.
 
Pan (chimpanzee) 2.2-2.5
 
Macaca mulatta 2.1
 
Elephants 1.13-2.36
 
Equus caballus 0.9
 
Ovis aries 0.8
 
My commentary:
Although Old World monkeys (here by the rhesus macaque) are less brainy than chimpanzees, the difference is not as great as many naturalists might suppose.

Ungulates (as represented by domestic horse and sheep) are far inferior to Old World monkeys, having EQ of <1, compared to the value of >2 for the rhesus monkey.

However, elephants are brainier than ungulates, having EQ of 1.1-2.4.

I do not know why the values for elephants show such a wide range, but note that the maximum value (2.36) is similar to that of chimpanzees. If we take the middle of the range for elephants (i.e. about 1.74), it is double the value for the domestic sheep and closer to the value for a macaque than to the values for the ungulates. This shows that elephants are indeed brainy for non-primates.
 
According to a different study (I think the source is Schoenemann P T (2004) Brain size scaling and body composition in mammals. Brain Behavior Evolution 63, 47-60):
 
Homo sapiens 5.07
 
Nasalis larvatus 1.11
 
Procolobus sp. 1.50
 
Erythrocebus patas 1.93
 
Cebus sp. 2.52
 
lemurs 1.0 or <1.0
 
langurs relatively small values for monkeys
 
Rangifer tarandus (wild) 0.78
 
Connochaetes sp. 0.68
 
Phacochoerus sp. 0.40
 
Hippopotamus sp. 0.27
 
Loxodonta africana 0.63
 
Tursiops truncatus 3.60
 
various dolphins 2.43-4.45
 
My commentary:
Elephants are clearly far brainier than hippos (0.6 cf 0.3).

Warthogs are less brainy (0.4) than ruminants (0.7-0.8), which I find rather surprising; but note the similarity in EQ between warthog and hippo, which makes sense in view of a multifacetted similarity in morphology, ecology and life history strategy between pigs and hippos.

This data-set does not show elephants to be brainier than ruminants, but other data-sets (published by other authors) do so.

This data-set shows capuchin monkeys of South America (which are the brainiest of all non-human primates) to have EQ 2.5, compared with the human value of 5. There are no apes in this list, but note that the EQ value for capuchin (2.52) exceeds even that for the patas monkey (1.93), which is among the brainiest of Old World monkeys and apparently (see below) brainier than baboons.

Nobody should be much surprised that the patas monkey, which is exceptional among monkeys in living a quasi-cursorial existence in predator-infested African savannas without the benefit of cliffs or trees to take refuge in/on, is almost twice as brainy as the proboscis monkey of Borneo, which lives on a large island and eats leaves, which swell its body mass with bulky fibre.
 
Different values again were calculated by Martin (1984) and Jerison (1973). In the list below I present them in this order, i.e. Martin’s and then Jerison’s, separated by the word ‘or’.
 
Homo sapiens 6.28 (according to Martin 1984) or 8.07 (according to Jerison 1973)
 
gibbon sp. 2.40 or 2.60
 
Pan troglodytes 2.38 or 3.01
 
Pan paniscus 1.80 or 2.36
 
Macaca sp. 1.78 or 1.95
 
Cercocebus sp. 2.09 or 2.29
 
Cercopithecus sp. 1.96 or 2.05
 
Nasalis larvatus 1.07 or 1.24
 
Procolobus sp. 1.27 or 1.41
 
Papio sp. 1.74 or 2.05
 
Erythrocebus patas 1.99 or 2.19
 
Cebus sp. 3.25 or 3.25
 
My commentary:
Note that South American capuchin monkeys (which use tools and share food) have EQ (3.25) far greater than that of baboons (1.74-2), which makes sense. Capuchin monkeys actually exceed apes in EQ (the latter in this data-set having values of <3). Baboons have similar values to macaques and guenons.

Mangabeys and the patas monkey seem superior to baboons in EQ despite being less gregarious, which I find puzzling.

Colobines such as the proboscis monkey are clearly inferior to cercopithecids in EQ, which may be partly owing to their gut-fill with bulky leaves.

Note that, although everyone agrees that chimpanzees (genus Pan) are exceptionally brainy, it is by no means true to say that the EQ values between chimpanzees and cercopithecids fall into non-overlapping ranges. In fact there is considerable overlap, which means that the most familiar genera of apes are not categorically brainier than Old World monkeys.

For example the EQ for the bonobo is 1.8-2.4 according to these authors, compared to similar values for mangabeys (and the patas monkey not far behind).

It is true to say that a gibbon (2.4-2.6) is categorically brainier than any Old World monkey (for which all values fall <2.3), but this cannot be said for chimpanzees (Jerison’s value for baboon exceeds Martin’s value for bonobo).

And as I’ve already mentioned, capuchins (South America) clearly exceed chimpanzees in EQ.

It is interesting that the brainiest of apes seems to be a gibbon, despite the lack of gregariousness in gibbons. I.e. gibbons (2.4-2.6) far exceed baboons (1.7-2.1) in EQ despite the gibbons being incomparably less socially complex than the baboons; this really is an indication of the difference between apes and cercopithecids, but chimpanzees do not exemplify this as clearly. As in a study cited earlier in this email, it is remarkable how much less brainy the Bornean proboscis monkey is than the African patas monkey (<1.25 cf >2); this is only partly accounted for by the greater gut-fill (leaves) of the colobine, and otherwise reflects the far more hectic environment of the African monkey, which is by far the most extreme example of all non-human primates of living out on the open on one’s wits in a predator-ridden dry savanna with short sparse vegetation and no cliffs.

(writing in progress)

Anotado en 30 de junio de 2022 a las 04:56 AM por milewski milewski | 5 comentarios | Deja un comentario

Analogy between flowers and sexual swellings in monkeys

(writing in progress)

Baboons and other monkeys have extremely developed sexual swellings in the females around oestrus.

The main function of these swellings is to inform the males that the individual female is ready to copulate. However, there seems to be ‘overkill’ here, because the swellings are extreme to the point of absurdity. For an idea of what I mean here, visualise a nubile young woman going shopping in her local area with a full-length neon orange suit, a 1-m tall orange hat, and a banner reading in foot-high letters ‘I’m hot, I love boys of all sizes, my phone number is SEX069069’.
 
Way over the top, by any standards, not so?
 
It has just struck me for the first time that there may be a valid analogy here with colourful flowers in the plant world.
 
Now that I think of it, conspicuous flowers present a similar puzzle in at least certain plants. There are many ways to disperse and receive pollen. If animals are to be used as vectors, there are many subtle ways to attract them. Plants, particularly those growing in dense stands, hardly need to advertise themselves with such gaudiness, do they?
 
I suspect that the plants in question are doing more than simply ensuring that they get pollinated. What they are additionally trying to ensure is that many different individuals of the same species provide pollen to choose from. By ‘overstimulating’ the insects, for example, relative to the basic need of just a few visiting insects and just a few deposited grains of pollen, these plants ensure that the ovule has many ‘suitors’ to choose from when it comes to accepting the pollen grain that is to fertilise the ovule.

Just as sex in itself is somewhat ‘over the top’, considering that plants could theoretically reproduce vegetatively (e.g. by budding or suckering or various other methods of cloning), so the sheer size and gaudiness of some flowers seems ‘over the top’ in attracting a virtual frenzy of activity by pollinating animals.

Flowers seem in many cases to have evolved along the lines of extravagance rather than economy, raising the question: ‘if efficiency is at a premium, in which ways is it more efficient to have so many different pollen grains to choose from?’
 
The puzzle is compounded by the likelihood that such gaudiness can only increase plants’ attractiveness to their enemies, such as seed-killing insects. There is a price to be paid for self-advertisement, so the self-advertisement had better be worth it.
 
So, I could argue the following:
In one sense, gaudy flowers (particularly of plants that grow in dense stands as opposed to being scattered inconspicuously among other, larger and commoner, plants), achieve an agenda combining maximum choice of paternity with maximum testing of ‘immunity’ in the broadest sense.

Instead of doing what would seem to be the sensible thing, namely to keep a low profile and raise the sexual standard just high enough above the herbaceous horizon to attract the essential minimum of one pollinator, what really happens is exuberance on both counts: combining what amounts to an orgy with what amounts to a reproductive gauntlet.
 
So, do sexual swellings in baboons and other monkeys represent a combination of what amounts to an orgy with what amounts to a reproductive gauntlet?
 
Is the similarity between flowers and the sexual swellings of e.g. baboons not apparent, in their colour, their extent and complexity, and their delicateness and physical vulnerability? These are, to me, among the most ‘floral’ anatomical structures in the mammalian world. To human eyes they are far too ugly (indeed, quasi-obscene) to conjure up the image of flowers if one approaches the problem from an aesthetic viewpoint. However, if one approaches the problem from a functional viewpoint, is the analogy not evident? 
 
Humans tend to be so biased by our aesthetic sense that we appreciate showy flowers with little sense of their absurdity. However, if one ponder the costs of these structures even from just the point of view of evaporative losses, one may see that plants must surely have good reasons to configure flowers in the ways that they do.

Flowers are surely inconvenient in various ways inconvenient for plants to produce. We know of many plants – epitomised by grasses – that manage pollination using no showy structures, and the simple mechanism of wind.
 
What this all adds up to:

Most authors would not call sexual swellings in monkeys 'sex organs' outright. They might prefer to call them secondary sexual features or sexually related organs. However, how can the parts of the body subject to sexual swelling in monkeys not be described as sex organs?

I suggest that we can – at least from one perspective – view the sexual swellings of monkeys as the closest thing, among mammals, to floral organs. All flowers without exception are sex organs, and the sexual swellings of monkeys are, likewise, sex organs although I cannot recall them having been described with such candour in the literature.

(writing in progress)

Anotado en 30 de junio de 2022 a las 04:35 AM por milewski milewski | 0 comentarios | Deja un comentario

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.

(writing in progress)

Anotado en 30 de junio de 2022 a las 04:03 AM 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

(writing in progress)

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:
http://www.environment.gov.au/system/files/resources/d6c37be6-42cd-48c4-9cb6-9919457c8898/files/dasyurus-geoffroii-2012.pdf

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):
 
http://i9.photobucket.com/albums/a70/troutylow/ReadyReleaseChuditch.jpg

http://thylacoleo.proboards.com/thread/3010/nannup-tigers 

Dasyurus geoffroii:
http://www.westernwildlife.com.au/Western_Wildlife/Chuditch_files/IMG_1866.jpg

Dasyurus geoffroii:
https://pbs.twimg.com/media/Br6QFQrCIAQFAgb.jpg

Dasyurus geoffroii (body mass about 1 kg), with adult female human for scale:
https://s.yimg.com/ea/img/-/150505/290415genchuditch2_1akgut2-1akgutd.jpg?x=656&sig=.qF3KUEX4HQM7vvLIVyfvA-- 
 
Dasyurus geoffroii with adult male human for scale, southwestern Australia (I think the photo is attributable to Ian Moone):
 
http://i9.photobucket.com/albums/a70/troutylow/ReadyReleaseChuditch.jpg 
 
http://thylacoleo.proboards.com/thread/3010/nannup-tigers 

Dasyurus geoffroii:
http://www.westernwildlife.com.au/Western_Wildlife/Chuditch_files/IMG_1866.jpg 
 
Dasyurus geoffroii:
https://pbs.twimg.com/media/Br6QFQrCIAQFAgb.jpg 

Suricata suricatta with adult male Homo sapiens:
http://i.dailymail.co.uk/i/pix/2012/04/09/article-2127209-1285B792000005DC-407_634x863.jpg

Suricata suricatta with adult male Homo sapiens:
https://i.ytimg.com/vi/_78mkyJCFzw/maxresdefault.jpg
 
Suricata suricatta with adult male Homo sapiens:
http://blog.corbis.com/wp-content/uploads/2014/11/42-63039353.jpg

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):
http://nnimg-a.akamaihd.net/silverstone-feed-data/d1c3e942-0a20-48c3-acfd-efa24cc66791.jpg

Dasyurus geoffroii (body mass about 1 kg):
http://www.australianwildlife.org/media/59030/Chuditch-Ali-D.jpg
 
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:
https://s.yimg.com/ea/img/-/150505/290415genchuditch2_1akgut2-1akgutd.jpg?x=656&sig=.qF3KUEX4HQM7vvLIVyfvA--

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:
https://www.youtube.com/watch?v=nqowT5swY_A 
 
Genetta genetta in Zululand:
http://smithsonianscience.si.edu/wordpress/wp-content/uploads/2014/09/Genet-rhino_3_watermark-e1411439284371.jpg

http://voices.nationalgeographic.com/files/2014/09/Genet-rhino_7_watermark-1024x789.jpg

http://smithsonianscience.si.edu/wordpress/wp-content/uploads/2014/09/Hluhluwe-Buffalo-and-Genet-1_edited_watermark-Wildlife-Act-630x451.jpg

https://bonnie8878.files.wordpress.com/2014/09/nature-genet-buffalo_1_watermark-1024x790.jpg?w=940&h=400&crop=1

https://i.ytimg.com/vi/YOrhmA1oUkQ/maxresdefault.jpg

(writing in progress)

Anotado en 29 de junio de 2022 a las 10:01 PM por milewski milewski | 1 comentario | Deja un comentario

The odd importance of primates in Madagascar

(writing in progress)

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:
https://en.wikipedia.org/wiki/Archaeoindris
 
https://en.wikipedia.org/wiki/Subfossil_lemur
 
re terrestriality in Hadropithecus, which was not particularly large but foraged on graminoids and tubers:
https://en.wikipedia.org/wiki/Monkey_lemur

(writing in progress)

Anotado en 29 de junio de 2022 a las 09:04 PM 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:
http://4.bp.blogspot.com/LbccUVbSRd8/SVVdMW3Xp1I/AAAAAAAADxw/tEpjS-f2VCM/s400/Chacma+Baboon+1.JPG
 
Papio ursinus adult female, innocent yawning in boredom:
http://media.gettyimages.com/photos/chacma-baboon-picture-id159015682
 
Macaca fuscata, showing that sexual dimorphism is far less than in Papio ursinus:
https://upload.wikimedia.org/wikipedia/commons/f/f8/Macaca_fuscata_male_and_female
,_Iwatayama,_20081019.jpg
 
Macaca fuscata, adult male yawning in boredom/relaxation:
https://c2.staticflickr.com/4/3133/3155084581_ea7907df3a_z.jpg?zz=1

Macaca fuscata, adult male yawning in boredom/relaxation:
https://toraninjapan.files.wordpress.com/2011/01/img_5447.jpg

Macaca fuscata, adult male yawning in boredom/relaxation:
http://cache4.asset-cache.net/gc/sb10069579a-001-japanese-macaque-in-hot-spring-gettyimages.jpg?v=1&c=IWSAsset&k=2&d=n6SjgRHExVfoo4Tnly7wvfaamXikwNLx%2FpyRIEA7xg8jNwzNPJzpPZyvTvZKaTugCHymUWs3C4zSP%2Fl%2BFmFCVg%3D%3D
 
Macaca fuscata, adult male yawning in boredom/relaxation:
http://www.visualphotos.com/photo/1x6771757/close-up-of-two-japanese-macaques-macaca-fuscata.jpg
 
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):
http://c8.alamy.com/comp/EAGCXE/a-male-japanese-macaque-snow-monkey-bares-his-teeth-EAGCXE.jpg
 
Macaca fuscata, ditto:
http://l7.alamy.com/zooms/d421b60790544e26be99e21f44277a9b/a-male-japanese-macaque-snow-monkey-bares-his-teeth-eagcxc.jpg
 
Macaca fuscata, ditto but in this case apparently an adolescent rather than mature male:
http://c8.alamy.com/comp/AB84X3/japanese-macaque-snow-monkey-macaca-fuscata-shouting-displaying-his-AB84X3.jpg

Macaca fuscata, ditto:
http://c8.alamy.com/comp/APNE16/japanese-macaque-snow-monkey-macaca-fuscata-shouting-displaying-his-APNE16.jpg

Macaca fuscata, ditto:
http://c8.alamy.com/comp/AB84X6/japanese-macaque-snow-monkey-macaca-fuscata-leaning-forward-shouting-AB84X6.jpg

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:
http://farm6.static.flickr.com/5535/10339069904_cfca603e50_m.jpg

Macaca fuscata, adult female yawning in boredom/relaxation:
http://cache.diomedia.com/230h/01/AB/FV/01AB-FVF2.jpg

Macaca fuscata, adult female fear-grimacing accompanied by appropriate vocalisation:
http://medias.photodeck.com/2f24b304-c599-11df-a40a-00270e09af22/JW_013110_2432_xgaplus.jpg

Macaca fuscata, ditto:
https://josephmallozzi.files.wordpress.com/2012/11/1294.jpg

Macaca fuscata, ditto:
http://natureinstock.com/stockphoto/187-92095/Japanese-Macaque-Macaca-fuscata-showing-teeth-in-hot-spring-90318.jpg

Macaca fuscata, ditto:
http://cache4.asset-cache.net/gc/123519839-japanese-macaque-calling-in-rotenburo-gettyimages.jpg?v=1&c=IWSAsset&k=2&d=oxs5zw4iBCbmtiIem9td9w6vqL6oROWbI7JKEBAXyzGKjOw4S1q2hWtz4nhiXVB5hyBm0hb67OJxSzwbGeIr8w%3D%3D

(writing in progress)

Anotado en 29 de junio de 2022 a las 08:19 PM por milewski milewski | 1 comentario | Deja un comentario

Sundry

(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 FUSCATA of Japan:

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/
-bdaw1HO6elfR8KEg_8w2Zo0lo=/1020x0/cdn0.vox-cdn.com/uploads/chorus_asset/file/2831182/Screen_Shot_2014-03-31_at_1.53.32_PM.1396288826.png
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)

Anotado en 29 de junio de 2022 a las 07:31 PM por milewski milewski | 0 comentarios | Deja un comentario