Andrew Hagen

The aquatic ape theory (AAT) postulates that human evolution has its roots in seagoing apes, or perhaps salt bog–trodding apes. (*) When I first ran into the AAT, I laughed almost all the way through, but then it seemed to make sense. Our ancestors would have lived in the trees. Their descendants lived in the water. Then, their descendants moved back to land. They became us.

In contrast, the standard theory of human evolution has human beings going from trees to savannahs, where our ancestors were hunters that stalked the plains. According to the standard theory, there was no aquatic interlude between trees and savannahs.

To sum up a few of the main AAT arguments: the relative lack of hairlessness on humans as compared to our closest living primate relatives, the bipedalism or erect walking of our species, the great amounts of sweat given off by human beings, and many other anatomical details put us in close relation to aquatic mammals. Analogues include whales, dolphins, and mammals such as elephants whose ancestors may have lived in the sea. One of the least scientifically compelling but most emotionally compelling arguments is that the strange human affinity for beaches is perhaps a hearkening back to a distant past.

Our aquatic ancestors would have lived approximately four to six million years ago. The evidence for the AAT is primarily anatomical. Fossil evidence does not exist. That might be explained by the lower likelihood of fossils forming in the wet environments where aquatic apes would have lived. Furthermore, the “Lucy” fossil has very long feet that Morgan has compared to flippers.

The AAT is not taken seriously by the scientific establishment. It has primarily been advanced in popular science books, like Elaine Morgan’s Scars of Evolution. This tends to stigmatize the theory.

Jim Moore has done the AAT a great service by attacking it. (†) Perhaps if the theory could be shown to withstand some good, hard critical scrutiny, it could attract more serious researchers.

My own thought is to take a group of human beings, move them to a secluded beach somewhere, take away all their technology, and have them to live as the aquatic apes would have. If we are a species in transition, we should be able to go back. As Thor Heyerdahl did (‡), the theory could be partially proven by re-enactment. If a group of humans could survive in such conditions, then that might be evidence for the AAT. (§)

Is AAT a scientific project that will advance our knowledge? That is not yet known. The AAT has a long way to go before it will be taken seriously by the scientific establishment. Still, the ability to know more about the human past is so important that it is worth the expending of great effort. If the AAT eventually falls, it falls. The higher goal is to advance scientific knowledge.

A discussion group is available. (**)

This entry was posted on Thursday, December 4th, 2003 at 01:53 and is filed under Natural science. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.