What is the Aquatic Ape Theory (AAT/H)?
The Aquatic Ape Theory (aka AAT
or AAH - I'll generally use the term "AAT/H" on this site) hypothesizes that humans went through an aquatic or semi-aquatic stage in our evolution,
generally said to have occurred during the transition from the last common ancestor we shared with apes
(LCA) to hominids (although some AAT/H proponents claim it continued on through virtually the entire span of human evolution).
It claims that certain features are seen in human
anatomy and physiology which are only seen in humans and aquatic animals
and that these constitute proof that our ape ancestors went through an
aquatic phase in their transition from ape to hominid.
Using the principle of convergent evolution, it says that life in an aquatic environment
explains these features, and that a transition from ape to hominid in a
non-aquatic environment cannot.
Who thought up the Aquatic Ape Theory?
Note: there are links to more detail on several of the AAT/H proponents mentioned below; you may want to read them now, but they may make more sense if they're read after this page and the next one (on AAT/H methods and problems).
You can also reach those pages from the links at the bottom of the opening page.
The original theory was done by
Sir Alister Hardy,
a marine biologist (an expert on plankton), who late in his career in 1960,
gave a talk at the British Sub-Aqua Club (a scuba diving club) and a month later published in New Scientist an article on that talk called "Was Man More Aquatic in the
It presented most of the basic ideas, and definitely the method,
of the AAT/H.
Desmond Morris then mentioned
Hardy's theory with a 2 page write-up in
The Naked Ape in 1967.
Elaine Morgan, at the time
an Oxford grad in English and a TV scriptwriter, entered the scene in 1972
with the book Descent of Women, the idea for which she got from
Desmond Morris's book.
This was a pop book, with a pretty chatty style which seems
dated now but was popular then, and it sold quite well.
Looking back at
it, I wouldn't call it particularly female-oriented (compare Morgan's notion of early female hominid behavior being the result of continual rape to more fact-oriented ideas like Tanner and Zihlman's idea of the selective power of sexual choice by females in hominid evolution), but Morgan presented
it as "the" alternative to what she then called "The Mighty Hunter" theory.
Morgan followed up with The
Aquatic Ape in 1982, The Scars of Evolution in 1990, and another
that came out in 1994, The Descent of the Child. Morgan says the
books after her first one are supposed to be "more scientific", but most
of the statements in them still aren't adequately cited -- it's difficult
or impossible to tie many of the statements in the text with the relatively
few refs given in the back. This makes it extremely difficult to provide
the in-depth critique AAT/H proponents demand to counter their theory (even
though the theory itself lacks this depth -- a classic double standard).
Morgan also has a creative hand when it comes to quotations, especially
quoting out of context in the manner of creationists. This too is made
difficult to discover by Morgan's habit of rarely giving sources for her
quotes, and even more rarely giving page numbers. This is counter to scientific
and journalistic practice, and despite Morgan's protests that providing
these references makes a popular book unpublishable, doing so is standard
practice in many popular, even best-selling, non-fiction books -- popular
biographies, for instance.
Morgan has written another
book on this subject (The Aquatic Ape Hypothesis, 1997); as a refreshing
change this time, she has included references for some, but by no means
all of her statements (this is perhaps to be expected since many of those
statements are false).
I haven't yet checked the
references for her quotes to see if this book is a change to her well-established
pattern of using misquotation, but it does still use most of the AAT/H's
established "false facts" to support her theory, including the thoroughly
discredited material on fat, tears, the larynx, hymens, direction
of the nostrils, etc., which this site covers.
I've done a critique of this book here on my site (the link to it is on the first page).
And in 2008 Morgan, bare months after saying she didn't have enough material for a sixth AAT/H book, brought out a sixth AAT/H book; I've critiqued that as well and that link is also on the first page of this site.
There have been a few other
people who've done articles on the AAT/H, and they belie Morgan's claim that
you can't publish academic articles on the subject. (Good academic articles
seem to be another matter entirely.)
Chief among them is Belgian medical doctor
who has done a number of articles.
Although Verhaegen's articles do have
references, they also contain statements such as claiming that rhinoceros
are "predominantly aquatic", and several other howlers among their many errors.
There was a conference in Valkenburg, The Netherlands, on the
subject in 1987 with both pro and con participants, and a book from that,
Aquatic Ape: Fact or Fiction?, shows the relative strengths of their
Although I'm sure any AAT/H proponent would disagree, the pro-AAT/H
articles in that book are distinctly amateurish compared to the ones which
don't support the AAT/H.
It's a good book to take out and read sometime
if you can find it, as it does cover the basic arguments and has some good
arguments to the contrary.
A short note: as it happens, when I wrote the preceding paragraph, I was wrong that AAT/H proponents would necessarily disagree that the pro-AAT/H articles in The Aquatic Ape: Fact or Fiction? were amateurish.
It turns out that Elaine Morgan agrees with me:
"It is quite true that the style of the opponents is more professional."
She excuses this inexcusable state of affairs with the true but untrue statement that
"The opponents were professionals."
This statement is true, but implies the others weren't, which ignores the fact that many of the pro-AAT contributors in that book were university-level professionals in scientific fields, albeit professionals who did unprofessional work.
And if she was talking about style in some way absent any context (ie. ignoring substance) let me point out that I was referring to their articles' competence, not some matter of stylishness without substance.
One AAT/H proponent has been saying for some time that I should have the conclusions from the Valkenburg conference on my site, so I've done a short page on that: The Aquatic Ape: Fact or Fiction? Conclusions.
After reading it you might wonder why he wanted it done, but that will remain a mystery for the ages.
In recent years it's become popular to point to a German-language publication on an aquatic hominid past from well before Hardy's, by a German anatomist named Max Westenhöfer.
As a note of historical curiosity this could be sensible, but there seems to be a thought that it somehow legitimizes the idea of the AAT/H.
However, there is no indication that Westenhöfer's "aquatic human" work influenced anyone within the AAT/H community, much less outside it.
This should not be surprising, since from the excerpts I've seen translated it was really chock full of wildly mistaken notions, and concludes, in the words of one translator (Patrick Beck), that Homo sapiens cannot be a close relative of primates, and even uses fiction as evidence, as in the statement "For example, to me the story of Beowulf's struggle with the dragon under water is a hint that humans perhaps did live and fight with such dragons in water".
This, to me, is not someone I'd like to claim is on my side :).
P.S. One thing I found from
posting on this subject in sci.anthropology.paleo is that Elaine Morgan
A) doesn't like it when you
imply she is the primary proponent of this theory (she is certainly the
best known and widest read); and
B) doesn't like it when you
mention any claims made by AAT/H proponents other than her.
But this seems to be contagious; Marc Verhaegen now also often takes umbrage if you critique an AAT/H claim that he doesn't make himself.
But then taking umbrage seems to be a specialty with him; his online method tends toward gratuitous insults, often as the sole content of his newsgroup posts, and continually reposting the same, non-responsive, paragraphs (earning him the nickname "macro-man" after the usual technique for doing that), and, starting from his very first online post in 1998, comparing his position to Wegener, Galileo, etc.
These methods certainly don't help his argument, instead placing his online newsgroup contributions in the realm of the netloon.
Michael Crawford and Stephen Cunnane
are in the forefront of a group of nutrition specialists who, over the past decade or so, have embraced the AAT/H as supposedly giving support to their goal of promoting DHA in modern diets (this is the one of the fatty acids, often referred to as Omega-3 fatty acids, required for proper brain growth and is dealt with in more depth later on this site).
They're academics in the general field of nutrition and they are trying to do something good, but their AAT/H work shows them to be seriously ignorant of evolutionary theory.
The good thing they want to do is push the addition of DHA into foods, such as milk and eggs, much as we have long added vitamin D to milk.
This is useful because many people don't eat the kind of diet that would give them a proper dose of DHA or LNA, as our ancestors' diets would.
The push for additional DHA in modern diets is overall a good one, in my opinion,
but in trying to tie this laudable goal in with a dubious theory, they do themselves no favors.
is a former graduate student who has been writing (mostly online) about the AAT/H for several years now, and can often be found promoting the idea that bonobos are bipedal 92% of the time they are in water.
This statement comes from a 5-hour portion of a 3-day study he did for his masters thesis, and refers to a total of 38 seconds his bonobo group spent in water during that study period.
This percentage is curiously, and wildly, at odds with all other studies, which creates the question of why it's so different.
Although asking this "why?" question would be a normal part of any scientific observation and although I can readily think of several likely reasons for this difference, this obvious question appears not to have occurred to Kuliukas.
This, sadly, seems to be the norm for him, and along with other indications, makes it seem unlikely that he will break the pattern of poor AAT/H research.
Kuliukas uses as a time period for the AAT/H essentially the same "non-time period" as Verhaegen -- the entire span of human evolution.
He has also suggested (somewhat like Verhaegen) that hominids spent very little time in the water, but this supposedly "milder" view is actually more radical than Hardy's and Morgan's for reasons I explain in the page specifically about his ideas.
The BBC has done both a TV program (rebroadcast in North America in essentially the same form by The Discovery Channel) and radio program on the AAT/H, the TV program in 1998 and the radio program in 2005.
Both are rather credulous (particularly sad to say of the radio program, which was done by Sir David Attenborough) and both are critiqued on this site:
critique of BBC Radio 4 program, "Scars of Evolution" by David Attenborough and
Critique of BBC/Discovery Channel documentary The Aquatic Ape
When honest scientists have facts
pointed out to them which prove their line of evidence is wrong, they drop
that line of evidence.
AAT/H proponents rarely do, and even when they
do, others -- both active proponents and casual aficionados of the idea -- often continue to use it.
Sometimes the very same person who
says they've dropped it continues to use it (as in the Morgan example below).
But if some of this evidence has been dropped,
why do I bother documenting its inaccuracy here?
There are several reasons:
Although some of these ideas are
dropped by one AAT/H proponent, other AAT/H proponents continue to use them. For instance,
while Elaine Morgan says she dropped the "swimming babies evidence" after
her 1982 book, Marc Verhaegen has continued to use it (without noting that
it is a response common to all infant terrestrial mammals tested).
Even though an AAT/H proponent may say
they've dropped an idea, the same person may actually continue to
For instance, in the sci.anthropology.paleo newsgroup post quoted
below (from 13 July 95) Elaine Morgan says she dropped the "evidence" about
the direction of the nostrils after her 1982 book, but she subsequently
began using it again online -- starting 14 July 95: the following day(!).
She's also using that info, as well as the salt, sweat, and tears info
she said she'd dropped, in her latest book.
Also online, we've seen Elaine Morgan
sometimes publicly drop lines of evidence, yet in the next sentence she's
claimed that the evidence is mounting:
From: Elaine Morgan
in sci.anthropology.paleo on 13 Jul 1995:
Note: All these things, however,
were stated in 1982's The Aquatic Ape (although Morgan had also
falsely claimed her inaccurate statements about the evolution of the nose
only appeared in her 1972 book).
"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. New evidence for AAT comes in faster than
anything I have to keep in abeyance pending further facts."
From: Elaine Morgan
in sci.anthropology.paleo on 19 Jun 1995:
If they have indeed been dropped
from the roster of AAT/H evidence between then and 1990, it sounds like evidence
is disappearing rather than accumulating.
"The nose - yes, I did once
make the mistaken assumption that the nasal spine was in evidence prior
to H. erectus. That was about twenty years ago and was never repeated.
You really are scraping the barrel."
And finally there is that Darwin
quote you saw as you entered this site -- "False facts are highly injurious
to the progress of science, for they often endure long..." The AAT/H has
provided us with a plethora of "false facts", and even those which have
been dropped by some AAT/H theorists continue to pop up again and again.
Far more than the theory itself, these false AAT/H "facts" are indeed "enduring
long"; having to go back and painstakingly refute them each time they reappear
is time consuming and debilitating, and so they are -- as Darwin pointed
out over 100 years ago -- highly injurious to the progress of science.
What about credentials -- do they matter?
Not to me.
Some AAT/H critics
point out that AAT/H proponents don't seem to have any formal academic credentials
which prepare them to theorize about human evolution.
Alister Hardy, though
a respected marine biologist, had no background in anthropology-related
studies; Elaine Morgan was and remained a television scriptwriter; Marc Verhaegen is
a medical doctor; Algis Kuliukas is a post-graduate anthro student; Michael Crawford and Stephen Cunnane are academics who specialize in nutrition.
I don't think this matters one whit... as long
as AAT/H proponents do the research that's needed to build a new theory.
Unfortunately, to date none of them have.
Do scientists care about this lack of credentials?
I think some of them do, and they're wrong.
Does science care about formal credentials?
I have a two word answer: Alan Mootnick.
Alan Mootnick is a gibbon guy.
He has no formal academic credentials; and he's entirely self-taught, yet he's
He writes both academic and popular articles, gives
presentations at academic conferences, and has gained the respect of primatologists.
How did he manage this?
By doing the work.
If you do the work;
dig out real facts and report them accurately, and make logical conclusions
from those accurately reported bona fide facts, a self-taught non-academic
is listened to.
Unfortunately, this process of digging out actual
facts and reporting them accurately, and of making logical conclusions,
does not describe the AAT/H research to date.
A reader pointed out to me in feedback from this site that another widely known example of someone who does the work well, without formal credentials, and is widely respected for it, is Richard Leakey (or the entire Leakey family, for that matter), and that another, perhaps less well known example is Kamoya Kimeu, one of the better known fossil hunters in east Africa.