Controversial Aquatic Ape Hypothesis
man's ancient ancestors live in the sea? (Copyright
Lee Krystek, 2008)
A Zoology Professor's controversial theory about
how dwelling in water may have affected the evolution of man may
explain issues from our lack of body hair to our affinity for
expensive beach-front property.
In 1960 zoologist Sir Alister Hardy, the Linacre
Professor of Zoology in Oxford, made the decision to speak about
a theory he'd been ruminating over in the back of his mind for
almost 30 years. The theory was so unconventional that Hardy had
qualms about publishing it, but on March 5th he decided to present
his idea in a speech to the British Sub-Aqua Club in Brighton.
Shortly afterwards he also wrote two articles for the Journal
New Scientist about his theory and the Aquatic Ape Hypothesis
(though Hardy didn't call it that at the time) was born.
Hardy's theory was simply this: That during prehistory
man's hominid ancestors had spent considerably more time in shallow,
coastal or lake water than most scientists had previously thought.
This, in turn, changed the way humans had evolved. His thinking
came from a book by Wood Jones called Man's Place among the
Mammals. In this book Jones stated that man, unlike all other
land mammals, has his fat attached to his skin. Hardy, who was
an expert in animals such as whales, thought that this sounded
like the trait of marine mammal. This suggested to him that mankind
had spent enough time in the water to cause him to adapt to that
Hardy wasn't the first one to ponder this possibility.
As far back as the Greeks, the philosopher Anaximander proposed
that mankind had come from an aquatic species of animal. The German
scientist Max Westenhöfer also speculated about this in 1942.
It was Hardy's speech and writings; however, that really brought
the theory to the attention of the world
Though no evolutionary scientists took to Hardy's
hypothesis, other people liked it. The zoologist Desmond John
Morris talked about it favorably in his 1967, best-selling, popular
book The Naked Ape. Writer Elaine Morgan read about the
idea in Morris' work and liked it so much she promoted it in six
different books. Morgan, a feminist, found the theory appealing
in part because the accepted theory that man evolved on the savannah
as a hunter seemed too male centered to her.
Naked, Breath-Controlled, Bi-pedal Ape
Over the years supporters of the Aquatic Ape Hypothesis
have compiled a long list of characteristics they observed that
man has in common with aquatic animals, but not apes. Probably
the most obvious of these is the lack of body hair. With the exception
of the head, most humans have very little body hair as do whales,
dolphins, walruses and manatees. The thinking is that if these
animals found it advantageous to shed their body hair as they
spent more and more time in the water, it might be the same for
Another characteristic is breath control. While
people can take conscious control over their breathing, apes cannot.
Of course without this capability swimming underwater is nearly
impossible. Proponents of the Aquatic Ape Hypothesis argue that
humans developed this ability to take over the control of their
breathing because of their extended time in the water. They also
note that the human ability to control breathing, which would
have evolved from a diving skill, may have been pivotal in his
later developing the ability to speak.
Supporters of the theory also think that bi-pedalism,
the ability to walk on two legs, might have evolved because our
ancestors were forced to deal with lands that were continually
flooded. A tall, upright gait would have assisted them with keeping
their heads out of water. The buoyancy of the hominid's body in
liquid would also have helped to support the animal in this unnatural
position until evolution made the necessary adaptations.
Proponents of the Aquatic Ape Hypothesis think they
can even pinpoint a possible location where this all occurred.
The Afar Triangle, a low-lying area near the Red Sea, contains
some of the oldest human fossils ever found on the planet. This
area was flooded 7 million years ago and became the Sea of Afar.
Theory supporters envision some of our ancestors trapped on offshore
islands during this time while others lived in forests that became
swamps, salt marshes or lagoons. The primitive hominids there
would have to have adapted to the changes, moved or died out.
Finally, believers argue that our ancestors would
have found the open grasslands of the savannah, where competing
theories say man evolved, too exposed to predators such as leopards
or other large cats. By retreating into the sea, they could avoid
vs. Aquatic Ape
Believers in the Aquatic Ape Hypothesis claim that
the scientific establishment has unfairly ignored their theory
because one of its main champions, Morgan, was an outsider. Opponents
of the theory, however, argue that the problem with the hypothesis
is that it sorely lacks the real evidence needed to support it.
They claim that many of the characteristics listed as connecting
man with aquatic creatures are misinterpretations or simply based
on incorrect information.
Opponents of the theory admit that both man and
some aquatic mammals are hairless, but point out that so are some
land mammals like the elephant, some rhinos and hippos. While
hippos do spend a lot of time in the water, elephants and rhinos
don't, except for the occasional wallow. (Their hairlessness seems
more related to their need because of their large size to shed
excess heat). What's more, opponents point out, semi-aquatic mammals
- the category the theory places man in - includes otters, sea
lions and beavers, who retain their hair. The only aquatic mammals
that have lost their hair are those who have spent large amounts
of time in the sea for millions of years such as whales and dolphins.
However, these animals (which are some of the fastest in the ocean)
have lost their hair in order to reduce drag and give them a higher
top speed. Man, however, would get no appreciable gain in speed
from this change as he is simply too slow a swimmer in the first
place. It would be as effective as streamlining a riding mower.
The top speed of the mower is simply not fast enough for the aerodynamic
shape to help.
Skeptics also point out that while man has perhaps
the best breath control of all land creatures, other animals,
like dogs and even some apes, can control breathing in a limited
way. The standard theory that man's control over his breathing
is the result of developing a very advanced vocal language explains
why he is so good at it without needing to speculate about man's
ancestors being aquatic.
According to Aquatic Ape Hypothesis supporters,
man is the only land mammal that is bi-pedal. However, opponents
to the theory point out that there are also no aquatic mammals
that walk on two legs either. In addition birds (like storks)
that use their long legs to wade through deep water have lower
legs substantially longer than upper legs, something that people
in the wild can use group tactics to protect themselves
from big cats, but are still vulnerable to crocodiles if
they get too close to the water.(Wikimedia
Finally, opponents to the theory point out that
using the sea, or even a lake, as a haven from predators is problematic.
Modern chimps living near the savannah have little problem with
big cats, like leopards, as long as the chimps stick together
and use group tactics. However, even modern man with all his weapons
fears crocodiles which can inhabit fresh water lakes and rivers
or saltwater seas. Spending substantial time in the waters of
the ancient Sea of Afar would have been much more dangerous than
living on the savannah. Not only would man have been in danger
of crocodiles in the shallows, but as the water grew deeper it
would also carry the threat of sharks.
Front Property vs. Parks
The argument over the possibility of man having
an aquatic past is far from over. Proponents of the Aquatic Ape
Hypothesis continue to find reasons to argue that man is more
like an aquatic creature than other great apes, while opponents
from the scientific establishment point out problems with these
ideas. A sample of these items include the amount and arrangement
of fat on our bodies, the need for fatty acids to develop brain
size, the existence of large sweat glands on our body and the
ability to cry salty tears. Each of these characteristics leads
to interesting discussion on human development, but none prove
Interest in the theory was probably at its zenith
in 1987 when a conference, organized by the European Sociobiological
Society and the Dutch Association of Physical Anthropology, was
held in Valkenburg, Netherlands on the subject. Twenty-two papers
were presented. Twelve for the idea, ten against and two neutral.
The discussion as the meeting was animated, but in the end no
consensus on the topic was reached.
However, it was discovered recently that elephants
have an aquatic ancestor from 37 million years ago, the Moeritherium.
The existence of this tapir-like animal that probably had a lifestyle
not unlike modern hippos seems to have added some credence to
the Aquatic Ape Hypothesis as far as its supporters are concerned.
'If the elephants did it, why not humans?' is their thinking.
Even the most hard-line unbelievers in the theory
have to admit that of the great apes man seems by far the most
comfortable submerging himself in the water. The question is whether
our capability to do this, which depends on breath control, is
the result of evolving to be able to dive under water or a side
benefit from learning to talk.
Beach front property is some of the most expensive
and sought after real estate one can buy. Proponents suggest this
is because we have an affinity for it based on our ancestors'
aquatic habits. However an affinity for something does not prove
that it affected our evolution. One can even argue we also like
the savannah - an open grasslands punctuated with trees - just
as much. In fact, we build replicas of it wherever we go. We call
Krystek 2008. All Rights Reserved.