I became interested in the aquatic ape theory of evolution because it pointed me in a fruitful direction — testing omega-3 fatty acids (e.g., flaxseed oil), which turned out to have easy-to-detect benefits (better brain function, better gums). That is more than I can say for alternatives to that theory, such as the savanna theory. Marc Verhaegen, a Belgian doctor, has recently proposed a new version of the aquatic ape theory. Some of his main points:
- An extensive overview of the literature by Stephen Munro showed that virtually all known archaic Homo [= pre-Homo sapien] sites (including those in ‘savanna’) were associated with permanent water and edible shellfish.
- Only regular diving can explain archaic Homo’s pachy-osteo-sclerosis (POS), the extreme thickness and density of cranial and postcranial bones of most erectus-like fossils. . . . POS is only seen in slow littoral divers, e.g. dugong and manatee, walrus, Kolponomos, pakicetids, Odobenocetops, and Thalassocnus spp. Marine biologists agree POS has a hydrostatic function (ballast).
- The abundant brain-specific nutrients in aquatic foods (e.g. DHA, iodine) facilitated fast brain growth (sapiens’ poorer post-aquatic diet required a longer youth to grow the same brain size).
- Man is the opposite of a savanna inhabitant. Humans lack sun-reflecting fur, but have thermo-insulative subcutaneous fat layers, which are never seen in savanna mammals. We have a water- and sodium-wasting cooling system of abundant sweat glands, totally unfit for a dry environment. Our maximal urine concentration is much too low for a savanna-dwelling mammal. We need much more water than other primates, and have to drink more often than savanna inhabitants, yet we cannot drink large quantities at a time.
- Maps of human population densities show that, although we have become fully terrestrial today, we are still a waterside species, and almost half of human dietary calories still come from the water (e.g. rice, aquaculture, fish, shell- and crayfish).
I find the water-drinking point especially persuasive. We need to drink throughout the day, or at least feel bad if we cannot. Almost all workplaces, including cafes, have a source of water. This is inconsistent with savanna living and consistent with waterside living. The term aquatic ape is somewhat misleading. A better name would be aquatic-food ape.