Jim Moore's "AAT Sink or Swim?" Web Site
AAT Claims and Facts
This page goes over much of the same ground already covered on the leaflet page. Here Moore now lists out 23 claims made by the AAT. Not surprisingly each and every one is followed by a supposed 'fact' which contravenes the claim.
Many of the claims could be argued to be reworded repetitions. For example claims 4 to 7 all concern the claim that salt sweat and tears may be scars of an evolutionary past where they functioned as salt excretory mechanisms. But worst of all, none of the 23 claims were referenced with proper citations allowing them to be cross-checked. In fact only three of Moore's alleged AAT claims were ones I could relate to as being a fair reflection of the AAH view. (In my opinion claims 1, 12 & 13.) About half of the others (3, 7, 8, 9, 11, 14, 15, 16, 20, 22) were along the right lines but were distorted, exaggerated or otherwise misrepresented such that an AAH proponent would probably not endorse them. For example claim 8 ('Human infants naturally swim while other non-aquatic mammals' infants can't.') would be about right if it were 'Human infants naturally swim whilst infants of our closest relatives, chimps and gorillas can't'. The rest (2, 4, 5, 6, 10, 17,18, 19, 21, 23) were just bizarre claims either made by an AAH proponent early on, but which are no longer held with great importance (e.g. 2, 4, 5, 6, 18, 23 ) or which were made by unknown sources which Moore appears to have dug up to scrape the barrel of rotten tomatoes purely for the purpose of throwing at the hypothesis (e.g. 10, 17, 19, 21).
Of those three claims (1, 12 & 13) which were reasonable portrayals of the AAH view, the facts cited were weak in contradicting them. In 1 the facts were selective and incomplete. 12 was largely based on a etymological interpretation of the term catyrrhine instead of real observations of them and 13 was far too simplistic for such a complex subject and, in any case, used an argument which one of the most vehement AAH proponents uses: that brachiation is likely to have been as much a factor in the origin of bipedalism as wading.
This page took several hours to critique because Moore had not bothered to
cite a single reference for any of the claims he alleged were made by 'the
AAH'. The whole venture was flawed from the start, however, because of
course there is not one single AAH view. It would be just as ridiculous for
a creationist to find 23 claims made by an odd collection of Darwinists over the years with
23 conveniently selected facts to contradict them.
Claim 1: Human hairlessness is explained by an
This 'claim', like all the others Moore attributes to the AAH here and elsewhere, without a proper citation, please note, is worded in such an extreme way that make it difficult to defend. Any reader might think AAH advocates are rather dogmatic about this: Our hairlessness is explained by an aquatic past and nothing else. This would be a mistake, and it is probably Moore's deliberate intention to cause it. Most AAH proponents are happy, for example, with the idea that human nakedness also greatly benefited sweat cooling, as sweat cooling only makes sense when the water lost can be easily replenished.
But even accepting his claim, the 'facts' put forward
to contradict it are rather selective. Moore, for example, didn't mention
the fact that the aquatic mammals that aren't hairless generally either live
in cold or temperate climates or are very small, or both. Humans
probably evolved in tropical Africa and are among the largest of the
Claim 2: The pattern of human hair alignment is strikingly different from
apes and indicates streamlining for swimming.
presumably (no citation given again) is taken from Hardy's original (1960)
paper which was taken from Wood Jones's (1930) book 'Man's Place Among the
Mammals' showing the pattern of hair alignment in human infants. It is one
of the odd traits that the AAH has tried to explain over the years, but it
is not a major one. It would seem logical that if hair increases drag in
water (as shown by the Sharp & Costil (1989) paper, it is logical that
natural selection would have acted to remove it totally eventually, but
before that point was reached to re-orientate the follicle in order to
reduce drag even with the hair in place.
Again Moore is economical with the 'facts' he lays out before the reader.
Claim 3: The human body
responds the same to the act of standing up as it does to surgery or massive
haemorrhage but this reaction doesn't occur when standing up in water.
It is difficult to critique this 'claim' as there is not citation but it is likely to have been part of an argument Elaine Morgan used in 'Scars of Evolution' (Morgan 1990). Again the 'claim' is stated as an absolute position as if the hypothesis might stand or fall on it. The point Morgan was making, surely, was merely that the hydrostatic buoyancy provided by water would clearly help a would-be biped to move bipedally which otherwise might not on land.
The evidence for this is quite clear and is growing. Moore might be forgiven for not knowing about the study I did in 2000 (Kuliukas 2002) which showed that captive bonobos are over 90% bipedal in water, whilst less than 3% bipedal on land.
Moore's 'fact' is hardly a fact, but to be fair he, instead, encourages the reader to go to a link on aldosterone and bipedalism. When I tried this (on Feb 16th 2004) it did not find the aldosterone.htm page that it was linked to. Perhaps it was being updated.
Only humans and marine mammals shed salty tears.
Putting to one side whether the claim was actually made in such a strong way (no citation given) or whether the fact is correct (no citation given for that either), it would appear that Moore could actually be right about this one.
Morgan (1997:p108) admitted as much herself when she
wrote "Despite the lump in the throat, the original AAT theory of tears has
flaws in it. If there were any other theory that had no flaws in it, that
would settle the matter."
Claim 5: Only humans,
Indian elephants, and aquatic mammals cry emotional tears.
As with the example above, Morgan really has moved on from this view which, to many, was only ever a relatively minor point in the debate at best.
Claim 6: Only marine reptiles and birds have salt
Again it would have been handy if Moore had given a specific citation for this point. Even if it is correct, at best it means that one of the AAH proponents made a mistake. The salt excretion argument was never a central one, as it was difficult to decide if it was arguing for a marine or freshwater ancestry. The fact that such features as salt and sweat tears are so ambiguous may still be explained adequately in the context of the AAH. They could be taken to mean that our ancestors either moved from salt to fresh water habitats periodically over time or, alternatively, that modern humans are a hybrid of two different water-side dwelling hominids.
Claim 7: The human
response to salt indicates we evolved in a salt-water environment.
Moore's 7 claims so far on this page basically amount to just three, re-worded and re-packaged to make them sound more dogmatic and unlikely so that they can be easily dismissed. This, 'salt take 4' is really just the same kind of renounced claim as the previous three.
Claim 8: Human infants naturally swim while other
non-aquatic mammals' infants can't.
However this line of argument misses the very important point about cladistics. Humans' nearest relatives in the animal world, the chimpanzee, is a notoriously weak swimmer (see e.g. Angus 1971). It's infants are very different from ours in terms of their fat content. It is simply a fact of physics that human infants are more buoyant than chimpanzee infants. Gorilla infants are much closer to the chimp model than the human one. It would therefore appear that, compared to our nearest relatives in the animal world, human infants are far better suited to survive water immersion.
Claim 9: Only humans and aquatic animals exhibit the
Here is a classic Moore claim of a claim and claim of a
fact that really could do with a real citation to back them up..
Morgan wrote about this early in her first book: "This physiological mechanism is known as bradycardia, and is found in many diving mammals, even fresh water ones such as beaver and coypu. It is also found in homo sapiens." Morgan (1972:p34). That's pretty close to what Moore said but not quite. The word 'only' did not appear in Morgan's phrase but it did in Moore's.
In her next book, she included a full page graphic showing, dramatically, how man's bradycardia was comparable with some aquatic mammals. (Morgan 1982:p76) and on the following page she writes "He [Man] shares, for example [of aquatic adaptations], the 'diving reflex'..." but then writes "Sudden immersion also produces some heart-rate reduction in many land mammals: it is the degree of bradycardia which distinguishes the aquatics." Morgan clearly is not suggesting this is an exclusive trait to humans and aquatics and she just as clearly shows that she understands that the real comparison that matters here is between man and apes as she goes on to say ".. to achieve a comparison between man and apes in this respect would seem to be impossible. No non-human primate, such as a gorilla or chimpanzee, can ever be induced to put its head under water, let alone to dive, except by force. Under these circumstances, the consequent exertion, aggression and panic would affect the heart rate so as to render the experiment invalid." Morgan (1982:p77)
In Appendix One, statement 3, of that book we appear to find the guilty party... it was Hardy himself. Hardy's article written in Zenith, a student's magazine, seems to contain the form of words Moore was able to pounce on. Hardy wrote "It has been found experimentally that man has the remarkable adaptation which is only [my emphasis] found among mammals and birds that dive under water. It is called the diving reflex and now solves the puzzle of how sponge and pearl divers can remain for so long. It only happens if the face is submerged; it won't occur if he wears a mask. If he dives under water with his face exposed, there is an immediate reaction cutting down the blood supply to both the brain and the muscles of the heart." (Hardy 1977, reprinted in Morgan 1982:p155).
Now that phrase 'mammals and birds that dive under water', was that meant to be 'mammals, and birds that dive under water'? In other words, did the editor of the student magazine miss out a comma? We'll never know. Let's give Moore the benefit of the doubt and blame it on poor old Hardy. Was he the one who AAH proponent that claimed exclusivity for this feature? We'll see.
It was a topic she appeared to miss completely in 'Scars of Evolution' (Morgan 1990) and also 'The Descent of the Child' (Morgan 1994), so perhaps in her last book?
No, here Morgan is quite unambiguous. She writes "And scientists came to realise that these [diving reflexes] were not confined to diving species: they are present in all mammals." (Morgan 1997:p140) and "Thus, the fact that the diving reflex is manifested in humans is not in itself surprising or proof that our ancestors went through a semi-aquatic phase after the ape/human split." (Morgan 1997:p141). Again Morgan notes that the comparisons that matter are ethically impossible to do but ends by quoting a scientist who has perhaps studied this more than anyone, Erika Schagatay. She wrote: 'The diving response of trained humans is in the range of semi-aquatic mammals like the beaver and the otter, while that of untrained humans is in the range of terrestrial species such as the pig.' (Cited in Morgan 1997:p147).
Now what can we conclude after all that researching? (which took me an hour to do - Moore claimed that his web site was designed to make finding sources easy - why thanks, Jim!) .
1) We can conclude that any fair assessment of the AAH, and by that I mean from either of the two books available called the Aquatic Ape Theory/Hypothesis, it is clear that the AAH makes no such claim to exclusivity and only includes it at all to make the point that Man, like all terrestrial mammals, clearly has traits which are clearly adaptive to moving through water. If all terrestrial mammals have a diving reflex what is so surprising that man might have other traits to help him move through water too?
2) We can conclude that Morgan's first discussion of this was at best a little ambiguous and might have been taken as suggesting that this was an exclusive trait. And that Hardy's (1977) piece in Zenith also appeared to confirm Moore's claim but even there, it might have been taken the other way. Even accepting that both implied exclusivity, there were certainly enough later, unambiguous references to the diving reflex being seen in all mammals to have countered them. Moore could therefore have chosen to give the pre-1980 statements the benefit of the doubt but he clearly decided not to do so.
Claim 10: Only humans and aquatic animals can hold
This time, Moore at least provides a link to a separate page which does contain some good counter-arguments. That page is reviewed separately here but suffice it to say that, again, Moore, is exaggerating the AAH claim. It's that word 'only' again. Who said it? Moore doesn't tell us.
Claim 11: The descended larynx of humans is like that
of aquatic mammals, and must have arisen in an aquatic environment. Although
it's necessary to make all the complex sounds we use in speech, it cannot
have arisen for that purpose, because it wouldn't be useful for that purpose
in its initial stages.
Moore here twists the story to imply that he is spilling the beans on an AAH claim that the descended larynx is only found in some aquatic mammals. Well, anyone reading Morgan's books would have found that out from her directly. Morgan didn't write about the descended larynx until 1994 when she wrote a whole chapter on it. In there she makes it perfectly clear that the only aquatic mammals who share the descended larynx are the sea lion and the dugong. She writes "These two species are about as unrelated to one another as they are to humans. The descended larynx must have evolved independently in each of them, after their respective land-dwelling ancestors entered an aquatic environment." (Morgan 1994:p136-7)
Moore's final point is a good one, although he does not provide a source for the fact. The original AAH claim that human ancestors went through a distinct semi-aquatic phase post the last common ancestor of Pan and Homo but before the speciation of Homo itself does not appear to have much evidence to back it up and, consequently, most AAH proponents have revised that idea to either multiple phases of 'more aquaticism' both before the split and after the Homo speciation (e.g. Verhaegen et al 2002) or to one where hominids generally lived in slightly more aquatic environments that did the ancestors of apes. (The argument of this author).
This claim/fact diad should therefore also be dismissed as another misunderstanding/misrepresentation.
Claim 12: Non-human primates have nostrils that point
forward, unlike humans.
By this stage, the thought of spending another hour searching through all of the books looking for the location of this 'claim' because Jim Moore hadn't bothered to tell us where he'd got it from was not very appealing.
What other facts does Moore offer to refute this 'claim'? He writes Old World primates are "called Catarrhine primates precisely because their nostrils face down." This is only partly true. It is also the fact that they tend to have wet noses which gives them their name, as in catarrh. Just take a look at some photos of old world monkeys like marmosets, tamarins, guenons, spider monkeys etc, face on, and see for yourself in how many of them are the nostrils hidden from view. Moore appears to be grossly distorting the facts here based, it seems, purely on a piece of etymological research. In fact, scanning through all the beautiful photographs of primates in Rowe (1996) I have to agree that my own nose (reflected back to me on page 233 is pretty conspicuously bigger than the others on show.
Morgan then, I think was right when she wrote "Neither group [catarrhines or platyrrhines] has an arrangement in the very least like homo sapiens, who has taken the trouble to construct an elaborate cartilage roof over his nostrils and direct them neither forward nor to the side but straight down towards his feet." (Morgan 1972:p45)
Moore criticised Morgan's use of the proboscis monkey as an example and he may have a point there. The proboscis monkey shows a great deal of sexual dimorphism and it seems likely that the males' large nose may be, at least in part, due to those kind of factors rather than any propensity for wading. His criticism of the drawing of a young proboscis (Morgan 1997:p162) swimming with forward facing nostrils only just above the surface of the water also seems inappropriate.
However, Moore offers no 'facts' which explain the characteristics of the human nose himself. It is it's essential 'hood-like' nature which would appear most easily explicable as an aid for swimming and diving and Moore had not one word to say about that.
Claim 13: Our ancestors wouldn't have changed from
quadrupedalism to bipedalism, because initially bipedalism would be less
efficient than quadrupedalism.
Here, at last, is a reasonable claim/fact pair. Although the claim is not referenced, it is undoubtedly part of the argument for a wading origin for bipedalism. It is also a pleasant surprise that Moore at least provides an actual reference to one fact that might be argued refutes the claim. This is a first on this page too.
The Taylor & Rowntree data are surprising, certainly. However, Moore fails to inform the reader that their data was based on two young, perhaps infant (their ages are not given), chimpanzees and two capuchins walking on a treadmill and one has to question the statistical significance of such a small sample.
Moore also fails to inform the reader that several, if not most, proponents of the AAH now support an 'aquarboreal' model ancestor which adopted a wading-climbing lifestyle. (Verhaegen et al 2002) This is hardly contradicted by the brachiationist argument.
The subject of bipedal origins is a complex subject and requires more than a facile: claim-fact treatment to dismiss any argument about it.
Claim 14: Proboscis monkeys use bipedalism more often
than other primates and often walk bipedally as "merely an alternative
locomotor mode of getting from A to B."
Moore gives no exact reference for his quotation so let me do so here: Morgan (1997:p66) However, she makes no claim there that proboscis monkeys use bipedalism more than any other primate, just that "it regularly crosses quite wide stretches of water on two legs." (p64)
Her comments are indeed based on documentary film evidence, which is something. Moore's 'TV program' may have shown no such evidence absence of evidence is not evidence of absence.
The evidence of wading bipedalism in proboscis monkeys has, in any case, largely been overtaken in recent years by the the much more relevant evidence of wading bipedalism in Hominoidae. Orang-utans, gorillas (e.g. Doran & McNeilage 1998) , bonobos (Kuliukas 2002) and even chimpanzees (Karlowski 1996) have all been observed wading bipedally in shallow water. This, much stronger correlation between wading and bipedalism in much closer relatives to ours makes the wading argument very much stronger and therefore leaves Moore's counter-points on proboscis monkeys largely irrelevant.
Claim 15: It was too dangerous for our ancestors to
live on land during the transition from ape ancestor to hominid. The water
provided safety from predators.
Again, no reference was given for this claim, making it
difficult to verify the context of that argument. The case has been made by
many authors (only a few of which support the AAH) that an early biped would
have found life very hard out on the open grassland. Indeed this difficulty
was a major part of
Raymond Dart's idea - that the hard, cruel world of the savannah was the ideal place for the savage cunning he associated with humans to evolve. Moore's 'fact' again reveals Moore's exaggerated view of the AAH which has never argued that human ancestors lived in the water, merely that they moved through it from time to time.
The aquatic predator argument, like Dart's savannah predators, is not necessarily a weak point. The pressure from crocodile and shark predation would have a tendency to increase the selection for better movement through water. An early water-side hominid could climb a tree to escape a croc, but probably not a leopard.
Claim 16: Our ancestors couldn't have dealt with
predators on land, because the only way to do so is to run away, and we
weren't fast enough and there were no trees to climb.
This claim is rather a repeat of claim 13 but in addition appears to make the accusation that AAH proponents assume that savannah means 'no trees.' He doesn't cite a reference for this, of course, but it would seem unlikely. Moore is right to highlight how chimpanzees deal with predators (in his link he gives several references to works which show that chimps can deal with leopards relatively comfortably. See, however, Zuberbuhler & Jenny 2002 for evidence that leopards do kill chimps occasionally.)
Moore misrepresents the AAH argument here because implicit in it is the view that AAH proponents didn't think our ancestors evolved on land. This is not correct. Hardy's original idea suggested that human ancestors were more aquatic not that they were aquatic.
The body temperature of normal, healthy humans is the same as that of
whales, rather than our primate relatives or other terrestrial mammals, and
it doesn't fluctuate, while that of terrestrial mammals does.
Now that's one I'd never heard of before. Again, Moore makes no attempt to attribute the claim to any source so we have to take his word for it. This time I have to say that I could find no such claim anywhere. He might as well have said that AAH proponents claim the moon is made of cheese.
Hymens are an aquatic trait.
Vibrissae (sensory whiskers) are absent only in humans and in aquatic
Again, no reference. I could find no mention of this claim in any of Morgan's books or Hardy's papers. I can only assume it came from the infamous, unattributed 'AAT leaflet' dealt with in a previous page. It is an irrelevant point which appears to have been conjured up in order to scrape the barrel of rotten tomatoes to throw at proponents of the hypothesis.
Human fat quantity and distribution is like that of aquatic mammals; it is
adapted for insulation and swimming in an aquatic environment. Humans have
subcutaneous fat which is bonded to the skin rather than anchored within the
body, unlike non-aquatic mammals.
Although he does not argue that our fat tissue is like aquatics, William Montagna, arguably the world's leading expert in mammalian skin, contradicts Moore's 'fact'. He writes "Together with the loss of a furry cover, human skin acquired a hypodermal fatty layer (panniculus adiposus) which is considerably thicker than that found in other primates, or mammals for that matter." (Montagna 1985:p14).
Seals sweat through eccrine sweat glands, like humans, because aquatic
mammals lose their apocrine sweat glands.
Again, as this claim was unreferenced it made it difficult to verify it was ever made. I could find no such claim in Morgan's latest books but after setting off on what seemed like another wild goose chase I admit to losing a great deal of enthusiasm. Who cares how seals sweat? What has this got to do with human evolution anyway? Hardy's original analogies were made with aquatic mammals in order to try to shed some light on what evolutionary mechanisms may have made us naked and have a relatively (compared to most primates) fat layer of subcutaneous skin. It is possible to take this argument to an extreme, to argue that further parallels should be found. I think this is a mistake. The pro-AAH lobby do so at their peril because, clearly, humans never went through any phase as aquatic as that of a seal. The anti-AAH lobby do so joyfully, because with such distortions the AAH can easily be dismantled.
Human sebaeceous glands waterproof the skin, like the sebaeceous glands of
seals (and that "Sebum is an oily fluid whose only known function in mammals
is waterproofing the hair and skin.").
me to provide the reference Moore didn't for the quotation: Morgan
(1997;p153-154). Moore's alleged claim is another exaggeration. The claim is
not that human sebaceous glands waterproof the skin today but that "it could
be a relic of a time when our bodies were not only covered with hair but
with hair richly endowed with waterproofing protection." (Morgan 1997:p154)
This is not the same thing at all and makes the first 'fact' irrelevant.
Aquatic mammals copulate facing each other, like humans do, while other
terrestrial mammals don't.
This, in my
opinion, was always one of those AAH claims which was 'pushing it a
bit' and one that could be far better explained as a result of
bipedalism. So, I would agree with Moore's argument here, although I'm still
not sure which book that came from. Morgan certainly backs away from it in
her latest book. She writes "...on the ventro-ventral front science has
moved on. Accounts are coming in of other primates which have been observed
mating face-to-face" (Morgan 1997:p150).
Doran, Diane M; McNeilage, Alistair (1998). Gorilla Ecology and Behaviour. Evolutionary Anthropology Vol:6(4) Pages:120-131
Hardy, Alister (1960). Was Man More Aquatic in the Past?. New Scientist Vol:7 Pages:642-645.
Hardy, Alister, (1977) "Was there a Homo aquaticus?", article originally appeared in Zenith, 1977, vol. 15(1):4-6. Reprinted in 1982 The Aquatic Ape by Elaine Morgan
Karlowski, Ulrich (1996). The Conkouati Chimpanzee Refuge - a New Chance for Orphans. Gorilla Vol:1996
Kuliukas, Algis Vincent (2002). Wading for Food: The Driving Force of the Evolution of Bipedalism?. Nutrition and Health Vol:16 Pages:267-289
McGraw, M. (1939) Journal of Pediatrics, 485-490.
Montagna, William (1985). The evolution of human skin. Journal of Human Evolution Vol:14 Pages:13-22
Morgan, Elaine (1972). The Descent of Woman. Souvenir Press (London)
Morgan, Elaine (1982). The Aquatic Ape Theory. Souvenir Press (London)
Morgan, Elaine (1990). The Scars of Evolution. Oxford University Press (Oxford)
Morgan, Elaine (1994). The Descent of the Child. Penguin Books (London)
Morgan, Elaine (1997). The Aquatic Ape Hypothesis. Souvenir Press (London)
Sharp, Rick L; Costill, David L (1989). Influence of body hair removal on physiological responses during breastroke swimming. Medicine and Science in Sports and Exercise Vol:21 Pages:576-580
Tailor, J. A. & Tomkinson, M. (1975). A comparative study of primate breast milk. Reports of the Jersey Wildlife Preservation Trust, 12, 76-77.
Verhaegen, Marc; Puech, Pierre-Francoise; Munro, Stephen (2002). Aquarboreal Ancestors?. Trends in Ecology and Evolution Vol:17 Pages:212-217
Zuberbuhler, Klaus, Jenny, David (2002). Leopard predation and primate evolution. Journal of Human Evolution Vol:43 Pages:873-886.