A brief critique of Morgan's 1997 book,The Aquatic Ape Hypothesis
Elaine Morgan's
1997 aquatic ape book -- her sixth -- is supposedly her best researched (according to her) so I've read it and here jotted down some notes of things that I could immediately see were errors, problems, or logical fallacies.
This is instructive, since it shows just how
badly done her work is, and why it isn't accepted as reasonable; if it's
so easy to see major problems with something just at first glance,
what hope is there that delving into it at length will turn up a useful
scientific theory?
In this book, unlike her others,
Morgan has often (though not always) tied her specific statements to references.
You'll also notice she changed the subject from the Aquatic Ape "theory" to the
Aquatic Ape "hypothesis".
This first happened during the olden (mid-1990s) sci.anthropology.paleo
days, when Elaine showed up and people tried to point out to her the many
areas where her work fell short of, well, accuracy.
When folks in
the newsgroup also pointed out that her ideas were more properly called
a hypothesis, she took it as a massive insult and an ad hominem
attack (she called it a "new anti-AAT ploy"), and railed against the people
who pointed out the difference between "theory" and "hypothesis".
It seems she figured, like most lay people, that "hypothesis" means something
like "crummy theory".
It doesn't (for the differences, click here).
In chapter one Morgan sets
right to work on a favorite technique of hers, constructing a savannah
strawman.
This is one of the classic logical fallacies (see the link
to Steven's Guide to the Logical Fallacies on the links page).
Rather than use the actual descriptions of environments anthropologists say was
the transitional environment, and rather than use the actual definition
of savannah, she carefully builds a false version of these because a false,
"straw" version is easy to knock down.
Although savannahs by definition
are woodlands, and can be either dry or wet, Morgan's "savannah" is always
an arid, treeless plain.
A short definition of savannah
from the BioTech Life Science dictionary is "a type of woodland characterized
by a very open spacing between its trees and by intervening areas of grassland";
see the savannah definition on my page "What is the Aquatic Ape Theory?"
for more info.
Suffice it to say that the definition Morgan insists
be used is more than 100 years out of date.
One of the ways Morgan constructs
her strawman is seen on pg. 16 where, referring to the fossil "Lucy", she
says: "She did not die in a savannah habitat, but in a wooded and well
watered area", contrasting "savannah" and "wooded and well watered", which
is an incorrect contrast.
This isn't a new technique for her; it's
a staple in her work, for example, in her 1995 book, The Descent of
the Child, she refers on pg. 158 to the "scorching heat of the open
plains, the meagre vegetation, and the scarcity of water."
Many other
examples can be found in her books, articles, and online posts.
Morgan, by the way, has been
corrected on this subject many times over the course of the past decade.
Her response, honed during online interaction, can be seen on pages 17-18,
where she misleads the reader by claiming that the definition of savannah
used for the past 100 plus years is a new invention with which "younger
anthropologists" have apparently been duped by their elders "throughout
the ten years or so they have been studying the subject".
She's done
this before too, with phrases like "this new scenario".
Again, on
this subject she has been corrected many times.
Her continuing with
this wrong view, therefore, seems dishonest, although one can't be entirely
sure it isn't just incredibly bad research on her part.
But either
way -- whether dishonest or incredibly poor research -- it doesn't make
sense to insist that people accept an implausible theory based on it.
It's also rather mean-spirited to take advantage of lay people's unfamiliarity
with the subject by feeding them "false facts".
In chapter 2 Morgan continues
a familiar complaint about the fossil Lucy's presentation; that Don Johanson
and his coworkers made a point of leaving out the fact that the fossil
site where Lucy was found also contained remains of crocodile eggs, turtle
eggs, and crabs. She implies that this was a malicious sort of misrepresentation
of Lucy's environment perpetrated by people out to hide evidence.
That this evidence was "hidden" by publishing it in the official announcements
of the fossil's discovery makes it seem they did a mighty poor job of it.
Morgan, on the other hand, does rather better on her end, repeatedly talking
up the eggs and the crabs found at the site and neglecting to mention not
only the giraffes and elephants, but the many bovids, horses, monkeys and
baboons, hyenas, cats, rhinos, rodents, and pigs also found there.
We know that shorelines are good places to get fossilized, and that those
animals which frequent such places are fossilized more often than others.
This is also evidence which is ignored by AAT/H proponents, since, if our early ancestors
were frequenting shorelines,
we would expect to find far more than
the relatively few we do find.
Instead we find the sort of numbers
we might reasonably expect from an animal which was spending most of its
time elsewhere.
But it seems Morgan would have
it that if you die in hospital; you must have spent most of your life there.
On page 30 Morgan tells us
that crocodiles are just friendly, fish-eating fellows; which would come
as a surprise to people who actually study crocodiles, like Charles A.
Ross, croc specialist at the Smithsonian, who describes the Nile crocodile's
diet: "Very large animals eat antelope, zebra, warthogs, large domestic
animals, and humans".
Not to mention the 100-300 people killed by
them each year in Africa.
More info on the "Predators" page on this
site.
Morgan also makes the mistake, which could have been easily
corrected by minimal study, of assuming the smaller species of crocodiles
in the region of Hadar today are the very same types seen there, in a very
different environment 6-8 million years ago.
For Morgan, saying that predation
by crocs is a massive problem for the AAT/H is "something on a par with saying
that they could not have lived on the grasslands because they would all
have been eaten by lions."
But as you'll see on the "Predators" page,
we have a model for savannah-living primates similar to hominids being
able to survive in spite of predators -- savannah-living chimps.
So we know it could be done there, by animals which are similar to our
ancestors in size, intelligence, and birth rate (ie. population replacement
rate).
What we don't see is any such creature -- of any species --
in an aquatic environment.
Anywhere.
Page 31 presents us with a
beautiful, and unfortunately typical, example of the argument style termed
"special pleading".
Morgan attempts to deal with one of the 5 unanswered
questions I mention on my page "Relevant Questions for the Aquatic Ape
Theory".
These are about actual aquatic traits of mammals (as opposed
to the many claimed but not really "aquatic" traits the AAT/H uses) and I
ask, why don't we exhibit any of them?
The one she's wrestling
with is about aquatic mammals and the length of their legs; they have shorter
legs (or incredibly modified legs, like seals and whales) compared to their
terrestrial relatives.
Our australopithecine ancestors had legs and
arms which were the same length as our terrestrial relatives.
Why didn't they change?
Morgan's answer is that there wasn't time in
this "brief" period (Morgan: "a matter of two or three million years")
for skeletal changes.
She couples this with a strawman (again) suggesting
the question refers only to seals and whales, when it's actually all aquatic
mammals.
pg. 31: "As for the
conformation of the skeleton of the earliest hominids, it has been claimed
that if they were or had been passing through an aquatic phase their fossil
remains would show unmistakable signs of it, as do the skeletons of seals
and dolphins; their legs would have become shorter instead of growing longer
and their arms would have begun to turn into flippers."
Now if any critics had actually
claimed what Morgan says they (we) did, I'd have to say they're out to
lunch.
But of course they (ok, it was me, actually) simply said what
I did above.
Morgan decided not to tackle that very reasonable question,
instead making a phony version of it which she could successfully
attack.
That's just the strawman part; the special pleading part
is more serious.
You see, Morgan claims there
wasn't enough time to change the skeletal features of hominids during her
purported aquatic period yet, at the same time, she insists that there
was a massive change to the skeleton, specifically the pelvis during that
time and due to this aquatic period.
This means that she says there
was
enough time for these changes, but only for her changes, and not
for the ones that are ubiquitous aquatic traits in mammals.
This is the essence of special pleading; here Morgan uses a double standard
by insisting that her theory's equally great (or greater) skeletal changes
could take place even though the counterargument's skeletal changes could
not.
(She often does this regarding other features as well).
Oh, then she starts floundering
and suggests that (even though aquatic mammals all exhibit this trait vis
a vis leg length) we simply ignored our mammalian heritage and changed
like (some) birds instead.
Let's get this straight; you don't just
get to go down to the store, pick out an evolutionary trait from a catalog
of any animal feature, and install it, no matter how handy you think it
might be.
Phylogeny is, after all, the central idea behind evolution.
Real evolution, that is, not Morgan's version.
Chapter 4: Morgan suffers some
confusion in this chapter.
First she compares the energetics of running
in humans with that of unrelated quadrupeds, showing what might be expected
for a species which is particularly adapted for walking; we use more energy
than they do while running.
Then she gets closer to home, and even
more muddled.
She gets out her strawman kit
again, with her line: "Since 1970 one of the goals of anthropologists has
been to erase the image of human bipedalism as recklessly profligate of
energy."
Actually, researchers simply asked the question: We think
bipedalism would have been more energy wasting than quadrupedalism for
our earliest ancestors, but we don't have any data one way or the other;
shouldn't we do some experiments?
Rather than the conspiracy Morgan
sees, this is a pretty sensible way to do some science.
Why does
Morgan find this so suspicious?
Perhaps because it contradicts her
thesis that bipedalism was more wasteful.
Here's what they found.
First, even for chimpanzees
and capuchin monkeys (natural quadrupeds), running on two legs is no more
wasteful of energy than running on four.
Second, in another study,
walking by humans today is far more efficient than quadrupedal walking
by chimps.
So, contrary to Morgan's long-held beliefs, walking bipedally
was not likely to have been a disadvantage for our earliest ancestors.
Yet the thrust of the AAT/H's argument regarding bipedalism has been that
it could not occur without the support of water.
And Morgan has argued
this for more than a quarter century despite these facts being available
in published form, easily accessible to any researcher, since 1973 and
1980, respectively.
That's 4 Morgan AAT/H books since 1973, 3 since
1980, and only now has she bothered to look at the research on the subject.
But hey, she dismisses it anyway, so I guess it wouldn't have made any
difference to her theory-building.
But why should anyone be expected
to accept her theory if its premises are contradicted by currently available
facts?
In chapter 5 she outlines,
in somewhat dismissive style, a few of the reasons scientists suggest we
might have found bipedalism advantageous.
The major problem she's
always seen with this is that there are so many reasons, rather than the
one she suggests.
She seems to feel that having one reason only makes
one more likely to do something than having a dozen.
Think about
this: imagine you have two possible courses of action; there is one reason
in favor of the first course of action and a dozen reasons in favor of
the second.
Which course will you more likely take?
Personally,
I find that the more reasons I have to do something, the more likely I
do it.
Morgan apparently marches to a different drummer.
On page 66, Morgan makes (as
she often has before) the bogus claim that proboscis monkeys, which swim
well and fairly often, use bipedalism more often than other primates (all
primates use bipedalism occasionally) and often walk bipedally as "merely
an alternative locomotor mode of getting from A to B."
This is false.
Morgan's source for overturning years of observations by primatologists?
A few seconds of film showing some proboscis monkeys walking upright.
Then on page 70 she once again
shows a remarkable blindness of vision regarding evidence, as she gleefully
describes an example of an extant ape walking bipedally in water, "not
for display behaviour, or sentinel behaviour, nor for reaching up for food
on an overhead branch.
It was walking bipedally in order to get from
A to B."
Really?
Well, no, not really.
I too was fascinated to see these National Geographic pictures of
gorillas wading, as they often do in that particular area, while feeding
on plants.
My fascination was more to the total situation, but I
admit I also found it interesting that they exhibit exactly the sorts of
locomotor behavior as gorillas who aren't wading: walking quadrupedally
and standing for display behavior and to reach food.
And that photo?
The gorilla is standing stationary on two feet, staring directly at the
cameraman (who was on a platform) and its arms are clearly wet up to a
point about midway between the elbow and shoulder.
In other words,
we have a gorilla who was wading quadrupedally, saw someone, and stood
up -- typical gorilla display behavior.
Why didn't Morgan see this?
Because she didn't want to.
Nobody really wants to find evidence
that upsets their own theories, but anyone worth their salt accepts it
when they do, and anyone who doesn't can't very well expect their theory
to be accepted as valid.
Morgan opens Chapter 7 with
a quote from Darwin which she misrepresents in much the same way she did
to him in The Scars of Evolution.
The quote is "No one supposes
that the nakedness of the skin is of any direct advantage to man."
This quote is from Darwin's 1874 (1871 for the 1st edition) Descent
of Man, and Selection in relation to Sex.
Morgan leaves off the
last part of the title, but a lot of people in academia do that too, even
though they shouldn't.
No marks off for that then :-).
Big marks off for not letting
Darwin say what he actually said.
First let me say that everyone
should read Darwin.
He was a terrific writer as well as thinker.
His work is really readable and still thought-provoking; it's no wonder
his books were best-sellers.
He is one of our best science writers
ever.
You can get his books at any bookstore for dirt cheap, and
if that's not cheap enough, you can download them for free from Project
Gutenberg (there's a link on the links page).
When you read Darwin
you'll that a common Darwin technique is the use of a setup for a point
he's about to make.
He opens with a passage in which he plays Devil's
advocate, citing the supposed difficulty of explaining such a feature.
Then he explains it -- in near-excruciating detail.
Dishonest quoters,
such as creationists, often use the first part of one of Darwin's setups
as if it were the complete thought.
They will quote only the opening
passage and leave out the meat (creationist Duane Gish is reported to have
excused this by saying, "After all, you have to stop quoting somewhere.")
Morgan uses this technique
here, quoting the setup and ignoring the meat.
In the complete
sentence Morgan quotes part of, Darwin says:
"No one supposes
that the nakedness of the skin is any direct advantage to man; his body
therefore cannot have been divested of hair through natural selection."
He uses this as a setup for his next paragraph, which begins: "The absence
of hair on the body is to a certain extent a secondary sexual character;
for in all parts of the world women are less hairy than men.
Therefore
we may reasonably suspect that this character has been gained through sexual
selection."
Then he goes on to provide 7 long paragraphs of info
to support his contention.
Note too that Darwin's statement suggests
that adaptionist scenarios -- like the AAT/H -- do not explain the human
hair patterns; this seems to escape Morgan's notice.
On the next page Morgan sarcastically
derides the very idea of using the concept of sexual selection to explain
the pattern of hair seen in humans, lumping it in with Wood Jones' "numerous
quaint theories".
As we've also seen in her earlier books, using
sexual selection to explain these patterns really bothers Morgan.
Why?
Because using it makes perfect sense.
Darwin came up with the idea
of sexual selection to explain a certain type of trait, and this idea has
been accepted because, like his concept of natural selection, it makes
sense and has been confirmed by many observations over the course of more
than a century.
Traits which are due to sexual selection have a couple
things in common: they appear or change radically at puberty and they differ
between the sexes.
This pattern is true of several human traits which
Morgan and other AAT/H proponents claim are aquatic adaptations (natural selection)
rather than due to sexual selection.
These are the pattern of hair
growth, the sebaceous glands (and complimenting this the scent receptors),
and the pattern of fat in humans.
In aquatic mammals these features
are the way they are by the end of infancy, and change little after that.
If you've gone through puberty, or know someone who has, you know this
isn't the way it is in humans.
It's not easy to ignore this obvious
fact, and it's so easily evident to anyone who looks at the people around
them or themselves, that Morgan's only recourse is to try to bury the concept
of sexual selection.
She uses the shovel of sarcasm, which can be
used, like any shovel, either to reveal or to hide.
So once you admit that -- as
even a glance around you would show -- human hair patterns differ radically
between the sexes and also change radically at puberty, you must be led
to the same conclusion as Darwin was:
"The view which seems
to me the most probable is that man, or rather primarily woman, became
divested of hair for ornamental purposes, as we shall see under Sexual
Selection; and, according to this belief, it is not surprising that man
should differ so greatly in hairiness from all other Primates, for characters,
gained through sexual selection, often differ to an extraordinary degree
in closely related forms."
Charles Darwin, 1871, Descent
of Man, and Selection in relation to Sex. (above from Project Gutenberg's
copy of the 1874 2nd ed.)
Oh yes, on page 72 she offers
a mea culpa about her previous quoting of Frederick Wood Jones about hair
loss, or rather the lack of it, in humans.
She says quite correctly
"I did not know its origin" but she completely misses the point about the
fact that what she did wrong when she quoted him by proxy (she got the
quote from Desmond Morris's The Naked Ape), was that she simply
made up the situation whereby Morris got the quote.
I guess she thought
it sounded good to say it was said during a TV show rather than a 1929
book.
Since she apparently quoted it in order to deride the thought,
perhaps she felt the made-up TV reference made it seem less authoritative.
Odd for a professional TV writer, but the world is sometimes an odd place.
(Shame she never offers any thanks to the person who pointed out the actual
source of Wood Jones' quote. :-)
So Morgan inadvertently teaches
us another point to remember about science if you want to be taken seriously:
don't just make stuff up.
You want to read about the
creationist style I referred to in quoting Darwin?
Just click
here.
In chapter 8 one immediately
sees Morgan having trouble with the evolutionary concept of "convergence"
(there's a definition on the "What is the Aquatic Ape Theory?" page).
She's attempting to find a way around the fact that convergent features
which are due to environment are generally found as a set of traits
shared by relatively unrelated animals.
The reason she finds this
a problem is that there are ubiquitous traits among aquatic mammals, yet
none of them are found in hominids; while her purported aquatic traits
are either actually nonexistent, not shared with aquatic mammals, or unique
to humans.
Talking about arctic animals and their white fur or feathers,
she says "But the Arctic fox and the Arctic hare and the others have converged
in respect of one single trait only." (pg. 79).
But this is
not true, as even minimal study would have told her.
In fact, it was pointed out to her online before this book came out, as I described on my "General Problems with the AAT/H"
page.
Besides the
white coats, these convergent arctic traits include feet covered by fur
or feathers, shorter extremities, and small ears, all of which help to
contain heat rather than radiate it.
(We see the converse in the
arctic fox's relative the Fennec, a desert fox with enormous ears which
act as radiators.)
These arctic traits are well
known and oft-discussed; it would be easy for anyone who is doing even
the least amount of research into convergent evolution to report this accurately.
That Morgan did not suggests either a deliberate misrepresentation or very
shoddy research; neither encourages one to have confidence in her work.
Pg 79: She uses the earlier
studies of Scholander et al., conducted using the skin and fat of dead
animals, to claim that fat is a better insulator than fur for these arctic
species.
But later studies with living animals, which were conducted
well before Morgan began her AAT/H work, showed that the reverse is true
in living animals.
In the next few pages she spends
some time trying to convince us that elephants, pigs, and rhinos are "in
some degree aquatic".
From her explanation this apparently means
they can swim pretty well (and many times AAT/H proponents treat such habits as wallowing
in mud as "aquatic").
In this sense virtually all mammals could perhaps
be said to be "in some degree aquatic."
Then she mangles the problem
of size and thermoregulation.
Large animals have less surface area
compared to their volume than small ones, and consequently, they lose heat
less rapidly.
This causes a build up of heat and is correlated with
less body hair, except for those large mammals in cold areas (think woolly
mammoth and rhino of the ice ages versus their present-day tropical cousins).
Morgan, on page 85, insists this can't be so because bison have hair and
pigs don't.
She ignores the facts that bison are not tropical mammals
(been to Alberta or South Dakota in the winter lately?) and that non-tropical
non-domestic pigs (and some tropical ones) have plenty of hair.
Later that page (pg. 85) Morgan
makes an even more bizarre statement about Galapagos tortoises and their
shells; she apparently doesn't understand the concept of tortoise shells
as protection.
I wouldn't have believed that one if I hadn't
read it myself.
Chapter 9 offers us some misinformation
on fat.
Page 88 mentions Rose Frisch's statements about female fat
requirements for menstruation (and therefore reproduction) but not the
research that showed her percentage requirements to be too high.
Morgan also repeats the statement about humans having ten times as many
adipocytes (fat cells) as would be expected in an average mammal of similar
size, which she gets from Caroline Pond's 1987 article which points out
that this feature of relatively small and numerous adipocytes, is common
to humans, fin whales, hedgehogs, monkeys, and badgers, and not rats.
Why did Pond mention rats?
Because Pond was pointing out that rats,
with their relatively large and few adipocytes, are not appropriate models
for fat studies in humans, and that other mammals are a better fit.
Pond also points out, in the same article, that captive monkeys which are
not as lean as wild monkeys also have a similar ("ten times the..") number
of adipocytes, but Morgan either misses or ignores this info, as she has
since she first cited Pond's statement over a decade ago.
On page 91 Morgan again takes
one of those ugly facts Huxley talked about 100 years ago ("a beautiful
theory destroyed by an ugly fact") and attempts to bury it with her sarcasm
shovel.
It's about hippos this time, and the ugly fact is that these
aquatic animals aren't very fatty.
That is, they're plenty round,
but they don't have very much fat -- the AAT/H says they should, but they
don't.
Naturally, Morgan doesn't like that fact, so a quick sidestep
is in order; she accomplishes this by saying (pg. 91) "It is true that
one article in the New Scientist stated in respect of the hippopotamus
that contrary to appearances '...it is certainly not fat'.
But this
statement was made by a man who was trying to promote the marketing of
hippopotamus meat.
Perhaps what he meant was that a hippo steak would
be less marbled with fat and contain less cholesterol than a beef steak."
Actually, what the fellow meant
was the fact that a hippo just plain isn't very fat.
Morgan tries
to imply they aren't lean by talking about the thickness of the layer of
fat under their skin, but seems to be unaware that a very large animal
has very large dimensions in an absolute sense even when those dimensions
are not particularly large in a relative sense.
This is such an easy
point to understand that I feel reluctant to provide an example for fear
I'll seem to be talking down to my audience, but since Oxford grad Morgan
has a problem understanding this, maybe others will too.
So think
about, say, the Sumatran rhino -- the one rhino which spends a fair amount
of time in water, also known as the hairy rhino (darn those facts, eh,
Elaine?) -- which is a very small rhino even though at around 800-1000
kg, it's a very large animal.
In the absolute sense, it's
big; in the relative sense, compared to its 3500 kg relatives, it's small.
Starting with page 96, Morgan
attempts to come to grips with Caroline Pond (I keep wanting to refer to
her according to her specialty, but "expert on fat" seems unwieldy and
"fat expert" doesn't really work either).
Morgan has attempted in
the past to claim Pond agreed with her on the AAT/H, but somehow that seems
unlikely when the very first article of Pond's that Morgan cited contained
the Pond-authored sidebar "Not an aquatic ape--just an exceptionally fat
mammal".
Morgan then tried a new tack, claiming that though Pond
said that human fat characteristics weren't due to an aquatic stage, she
had no idea what it was due to, but since Pond has been saying (even in
that 1987 article) that it's due to sexual selection, Morgan's technique
there also rings false.
Here in chapter 9 Morgan begins with a double-pronged
approach to try to counter Pond's observation that human fat distribution
is just like that seen in other primates and very unlike that of the aquatic
mammals Morgan so wants it to be similar to.
First Morgan carefully builds
some false context to make it seem that Pond is talking about something
she isn't.
Morgan says:
Pg. 96: "So, it is
argued, we are not looking at a specifically human tendency for the adipose
tissue to desert the internal depots and fly to the periphery: it is merely
that 'An apparent shift in the distribution of adipose tissue arises
as a direct consequence of an increase in its abundance."
"But the same
thing applies to aquatic mammals like the seals."
The quote within the quote is
Pond; Morgan's preceding sentence suggests that Morgan's insistence that
humans have fat which is bonded to the skin and not to internal depots
is a reality that Pond is explaining.
But as Pond has explained many
times, this AAT/H idea is not reality.
The sentence after the quote
attempts to obscure the fact that fat distribution in aquatic mammals,
especially "like the seals", is radically different from humans.
This is even more true when you look at fat distribution over the life
history of aquatic mammals "like the seals" versus humans.
There's
more on this subject on the page "Fat and the AAT/H" so I won't repeat it
here.
On to page 97, and Morgan is
perplexed: "I find it hard to understand why she described the insulation
hypothesis as 'a major tenet of the Aquatic Ape Theory'." Well, besides
the references Pond provided for that statement, there's someone named
Elaine Morgan who's used it as such in virtually everything she's written.
Check out page 15 of Morgan's article in The Aquatic Ape: Fact or Fiction?
from 1991; page 59 of her 1995 book, The Descent of the Child; pages
111-112 in her 1990 book, The Scars of Evolution; and it's virtually
the entire argument of chapter 3 in her 1982 book The Aquatic Ape.
(That's the problem with putting things in writing.)
Pages 99 and 100 see Morgan
trying to kill the idea that human fat distribution is a sexually selected
trait by pointing out that babies are fat.
As she correctly points
out, "epigamic adornments appear at puberty."
She fails to see the
reasons this isn't a valid argument (or maybe she does and just thinks
her audience will buy it anyway).
One is that during childhood we
(both sexes) go through the leanest period of our lives, until puberty
radically changes our fat quantity and distribution.
The fat at puberty,
and the differences between the sexes (has anyone besides Morgan not
noticed this?) shows the classic signs of a sexually selected trait.
The other is that the fat period of babyhood corresponds to the long postpartum
developmental time in our species, which is unique.
There's nothing
else like it; not even close.
And it's apropos to note that all aquatic
mammals are the exact opposite in this postpartum period, having babies
which are quite advanced compared to similar terrestrial mammals, or which
grow very quickly, or both.
Also on pg. 100, Morgan suggests
that the fat differences between the sexes in humans was due to major differences
in habits of AAT/H females vs. males, with females being far more aquatic.
Interesting that she does so, since she also lists sebaceous glands as
aquatic adaptations (when they too are undoubtedly sexually selected);
the far greater incidence of sebaceous glands in male humans would then
have to mean that males were far more aquatic than females.
This
sort of mistake is called ad hoc reasoning.
To end this chapter, Morgan
takes another shot at misrepresenting Pond's position.
I haven't
checked out the quote Morgan uses in connection with this, but it looks
like her Darwin-quoting technique... more later when I've checked it out.
At any rate, the quote is about differences in fat between the sexes, and
so is not on the subject Morgan says it is, which is "Why are humans so
fat?"
Morgan says Pond has no idea.
The actual answer is, simply,
because we can get away with it.
This view is backed up by research
in other animals vis a vis predators, and there's more about it on my "Fat
and the AAT/H" page.
Oh yes, one of the researchers who's shown this
to be so?
Caroline Pond.
Morgan really gets to flailing
wildly in chapter 10, as she tries to salvage her claims that sweat and
tears are aquatic adaptations, while (almost) admitting that her evidence
was nonsense.
She opens with a self-serving quote from S.J. Gould,
"Error is the inevitable by-product of daring" without thinking that error
is also the inevitable by-product of using falsehoods as evidence.
There's a lot about salt, sweat,
and tears here on my site ("Tears and the AAT/H" and its subsection on Homeostasis,
"Salt and the AAT/H", "Salt glands", and "Skin, sweat, and glands" are the
pages); I won't repeat much here.
Suffice it here to say that her
past statements about salt excretion via sweat or tears violate basic principles
of physiology; stuff that's well supported and well known, and which has
been well supported and well known for long before she started writing
about the AAT/H and decided that established basic physiology was an encumbrance
her theory didn't need to conform to.
Page 115 implies that eccrine
sweating is less efficient than apocrine sweating (sweating via eccrine
glands is one of humankind's major claims to fame to date :-).
Seriously,
sweating through eccrine glands is why !Kung hunters could run down much
faster apocrine-sweating animals like giraffes.
We just keep going
and going, while the giraffe doesn't, because our eccrine glands can keep
going and going, while their apocrine glands work rather nicely for about
20 minutes and then need a lengthy rest and recharge period.
Hare
and tortoise stuff.
On pages 115-116 Morgan tries
again, despite the long-established facts of basic physiology, to have
sweat be a salt excretor.
It can't work; in fact, researchers on
the subject have commented that sweat glands seem constructed so as to
save salt.
Sure, some escapes, but we always, always lose far more
water than salt.
This is explained in more detail in the Homeostasis
subsection of the "Tears and..." page.
On the same page Morgan defends
her earlier salt claims by saying, "It was all drawn from respectable academic
sources."
She's trying to defend her validity as a researcher by
saying hey, I was just repeating what the experts said.
This is not
true; check my site's pages I mentioned above for examples.
Her sweat
salt claims were false, they did not say what the experts said at the time,
including those she cited, and her claims violated known basic physiological
principles.
There's really no defense for that.
On page 119 she says that "The
credibility of the AAT would indeed be weakened if..." and goes on to offer
several things that would do so; the second and third are "...or if it
had not been based on scientific data that had appeared valid at the time;
or if I had continued to believe in it when the balance of the accumulating
evidence clearly swung against it;..."
Both these things are true,
and the evidence on salt, which she distorted from the start, is just one
of the examples of that fact.
Chapter 11: Oh no, it's more
ad hoc reasoning, about the larynx this time.
The descended larynx
of humans is apparently unique only in that the hyoid bone descends with it, and is not at all like the descended larynx of those
few aquatic mammals who have it, but that doesn't stop Morgan.
The most ad hoc part of her larynx reasoning can be seen in the fact
that it isn't descended for the first 2-5 years of our lives, unlike the
larynxes of aquatic mammals which have descended larynxes.
Remember that our baby fat is supposed to be an aquatic adaptation.
According to AAT/H reasoning, this means that our larynx says our first few years weren't
aquatic, but our fat says it was.
Also, fossil evidence shows
the larynx wasn't descended until millions of years after the supposed
aquatic phase.
Maybe it was a delayed reaction.
I do that sometimes;
someone says "boo" and I jump several million years later.
I struck through the preceding paragraph of text rather than simply replace it because I didn't want to pretend my mistake hadn't been made.
At the time I wrote it, I really should've known better, because by that time there was newer and quite different information available.
And in fact Morgan should've used that info as well.
It turns out the descended larynx isn't at all unique to humans among terrestrial animals -- older research had been done on dead rather than living animals, and newer techniques allowed researchers to discover that various animals, including chimpanzees and various deer species (red deer, wapiti, and fallow deer at least) have descended larynxes, and many other animals have larynxes that descend when vocalizing -- in fact, it seems to be a primitive rather than a derived trait.
There's more about this on my Breath-holding, the diving reflex, the larynx, and the AAT/H page.
We enter chapter 12; on page
138 Morgan points out that apes, like other quadrupeds, have little or
no motor control over the muscles of the diaphragm which help us when we
talk.
Those who study this subject tell us this was overcome due
to our erect posture and bipedal locomotion; the muscles which otherwise
would be constantly in use for locomotion of forelegs were freed up, and
this turned out to be a valuable side benefit for vocalization.
Perhaps this is why our larynx, also useful in vocalization, didn't descend
for some millions of years after we started walking upright.
More strikethrough on the larynx; from the newer research it seems likely -- extremely likely -- that the larynx descending was not a late trait, but probably a primitive trait; from comparisons with chimpanzees, however, it seems the descending of the hyoid bone (which helps in forming sounds for more effective communication) was a later trait, probably as part of the suite of communication helpers that included the improved breathing control that was a side benefit of bipedalism.
(Of course Morgan will have none of that, as we saw last chapter.)
On pg. 138 Morgan repeats a
mistake she's made before, and which she's been corrected about.
The details are on my page "Can AAT/H proponents research be trusted?".
When
she talks about aquatic diving mammals which are trained to dive on command,
she says "the amount of breath it takes before the dive varies according
to what the depth of the dive is going to be."
However, this
study she's referring to doesn't mention breathing at all; it's about bradycardia,
the slowing of the heart when diving.
Swimming baby alert on page
144!
See my page entitled, appropriately enough, "The 'Swimming Babies'
reference" for info on this universal mammalian feature presented by AAT/H proponents
as a unique human/aquatic feature.
Interesting to note that since this book came out in 1997, she was likely working on it at the very time she indignantly protested that her 1994 book had no mention of the swimming babies info:
"In The Scars of Evolution you will seek in vain for a mention of hair tracts or swimming babies or the direction of the nostrils.
Elaine Morgan, sci.anthropology.paleo on 13 Jul 1995
I guess she was saving it for this book.
Chapter 13 is a grab
bag of goodies.
On pg. 151 Morgan informs us that hymens
are "common among aquatic mammals"; while toothed whales, seals, and sirenia have hymens, Morgan neglects to mention a batch
of terrestrial mammals with hymens, including humans and lemurs, guinea pigs, mole rats, hyenas, horses, llamas, elephants, rats, horses, and some species of galago.
On pages 152-153, Morgan muses
about the menstrual cycle, wondering why its about the same as the lunar
cycle.
Well, it's the same as the oestrus cycle of chimps, so why
the amazement that we so closely resemble our nearest relatives?
It should also be noted that although the lunar cycle is extremely regular:
The occurrence of
menstruation is an irregular event in the sense that women do not have
a constant cycle length.
In no age group do 28-day cycles occur more
than 16 per cent of the time, and further, any given woman menstruates
at her mean cycle length on only 16 per cent of occasions."
E.W. Wilson, and P.I.C. Rennie,
1976, The Menstrual Cycle, pg. 36
Morgan is attempting to draw a
correspondence between lunar tides and menstrual cycles, but to do so she
simply ignores the fact that it doesn't really correspond at all.
(I'm struck by the irony of being male and having to explain menstruation
to a woman.
Thank god for books.)
More false facts on pp. 153-154:
"Sebum is an oily fluid whose only known function in mammals is waterproofing
the hair and skin."
Sebum is the product of sebaceous glands, and
its primary function in most mammals with sebaceous glands is for scent
(think pheromones), although seals have large sebaceous glands which aid
in keeping the skin pliable (check out the page on "Skin, sweat, and glands"
for info on seal skin and seal sweat -- amaze your friends with arcane
facts about seal sweat!).
How can you tell if an animal's sebaceous
glands are primarily a sexually selected feature used for scent?
By now you probably see the pattern -- if it's not sexually selected but
due to aquaticness, it's active and functioning when the creatures hit
the water; if it's sexually selected, it becomes active and functioning
at puberty, and probably differs between the sexes.
In seals these
glands are plentiful and workable by the first few months, when they start
swimming, and they are pretty much the same in males and females.
In humans these glands are incredibly scarce until puberty and those few
that do exist don't work much at all until puberty; plus they are far more
numerous in males, while females have better scent receptors.
That
screams sexual selection... it's a classic example of that type of feature
really.
Morgan suggests, on pg. 157,
that in humans the direction of the hair on the chest is good for
water flow around the body if you are "performing some approximation of
the breaststroke"; that would be an approximation which included keeping
the head (and beard remember) completely out of the water and the arms
held down along the sides.
I'd like to see someone actually do that.
I couldn't.
Pages 158-9 offers a pathological
condition often -- but not always -- due to exposure to water (ear exostoses)
as evidence of an aquatic past.
She's done something like this before
with an early Homo with signs of vitamin A poisoning (you'll see
this is "Relevant Questions for the AAT/H").
The problem is, if we
were adapted to an aquatic existence, why wouldn't this damaging susceptibility
to an ailment -- which causes ear infections and can rob us of hearing
-- have been weeded out through natural selection?
The fact that
it exists as a problem for us is evidence against an aquatic past
not for it.
This, by the way, is another classic logical fallacy,
called "Irrelevant Conclusion" (also called "Ignoratio Elenchi").
Pg 166 offers the idea that
differences in the percentages of haemogloblin and red blood cells in blood
of marine mammals and apes and humans constitutes evidence for the AAT/H.
Morgan, following the AAT/H proponent she got the info from, mentions the numbers
for apes and humans but not for marine mammals.
Wonder why?
Could it be because those numbers make the aquatic mammals seem just a
little too different?
For instance, about 60% higher percentage of
haemoglobin for seals as opposed to humans.
And that's just the tip
of the iceberg regarding these blood differences.
Marine mammals,
for instance, also have about twice the blood volume per kilogram
as humans, and ten times as much myoglobin in its muscles, which
is a protein which allows these mammals to store oxygen in their muscles
for diving.
They do this because they exhale when they dive, the
opposite of humans.
Morgan's AAT/H source, by the way, implies that
these other facts (marine mammals vs. humans) aren't known, and that this
is why he didn't provide them.
Well, they are known, and easily found at that (check out an encyclopedia for instance).
Why didn't he provide these facts that damage his case?
Why didn't Morgan?
Not mentioning available contrary evidence in this way is yet another logical fallacy,
the "Fallacy of Exclusion".
No one wants to mention contrary
evidence, but in science you have to -- if you want to be taken seriously.
Finally (I heard that sigh!)
we get to Morgan's last chapter, which is a page-long summary.
How
could you say anything incorrect in that small space?
Well, don't
underestimate Morgan, she's a trouper:
About the AAT/H, she says,
"The answers it offers are speculative, but no more so than those of any
other available model." (pg. 176).
I beg to differ.
No matter
what you call it -- theory, hypothesis, or model -- when it's built on
"false facts" and has so many holes that a first reading can find as many
as I have above, it's more than speculative.
It's way past speculative
and heading toward the realm of pseudoscience.
If AAT/H proponents want to
stay out of that realm, they need to heed the GIGO maxim, "Garbage in,
garbage out".
Unfortunately, if they do that, their "evidence" disappears.
Having been privy to the arguments
on sci.anthropology.paleo in the mid 1990s, I can see that Morgan was reading
and thinking about what was said.
Many of the arguments she makes
in The Aquatic Ape Hypothesis are reactions to critiques raised
there -- even the title itself and giving page numbers for quotes.
These points and many others were raised there, especially by Phil Nichols,
Alex Duncan, and me (it would've been nice if Morgan had given us a little
acknowledgment).
However, the point is that Morgan could have taken
these critiques to heart, because as that Carl Sagan quote I have on the
first page says, "Valid criticism does you a favor".
She could've
used the information we dug up to try to make a more valid theory,
but instead chose to just try to explain away some things, shovel over
others, and offer many of the same old discredited arguments and "false
facts" in a book which is superficially constructed to seem more scientific.
Sadly, rather than create a work of science, she chose to make a facsimile
of one.
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