Aquatic Ape Theory Revised

Did Humans Evolve from a Swimming Ape?

by Jerry Bergman, PhD

A strong indication of the scarcity of evidence for human evolution is easily seen—not only in the almost biannual major revisions of the theory (see my previous article, 18 April 2020)—but in the wide variety of contrasting theories proposed. On a regular basis, the news media announce new “paleoanthropological evidence has challenged [older] ideas about early hominid evolution.”[1] One of the most bizarre notions is the aquatic ape theory, the idea that humans evolved from some semi-aquatic creature. This is not a fringe theory. It has been widely and favorably covered in some of the leading peer-reviewed scientific journals since at least 1960.[2]

In 1960, eminent marine biologist Sir Alister Hardy suggested an aquatic phase in human evolution and, as evidence, noted Homo sapiens’ many major differences from the then-claimed human primate ancestors. In addition, proponents have cataloged many human similarities to other aquatic and semi-aquatic mammals.[3] Zoologist Desmond John Morris used Hardy’s aquatic ape hypothesis to explain “why we are so nimble in the water today, and why our closest living relatives, the chimpanzees, are so helpless and quickly drown.”[4]

Some impressive evidence has been marshaled in support of this theory, which needs to be addressed. It helps to solve, for instance, what paleoanthropologists agree is the major difficulty in human evolution: bipedal locomotion. Humans are the only bipedal mammal. Supporters of the aquatic ape theory postulate that imagining apes evolving in the water would help to resolve many other inconsistencies between man and the higher primates, such as the existence of paranasal sinuses in humans.

Other Homo sapiens–specific features that may be tied to a semi-aquatic stage of human evolution include erect posture, loss of body hair, deposition of subcutaneous fat, a completely different heat-regulation system from other primates, and kidneys that function much like those of aquatic mammals. This combination of characteristics, which do not exist in any other terrestrial mammal, would have gradually arisen over several million years.[5]

They also surmise that the aquatic theory may even account for man’s emergence as the dominant extant species in the world today, and even why the ‘missing link is still missing (because, the aquatic ape supporters claim we are not looking in the right place: an aquatic environment).[6]

The evidence noted above does less to prove the aquatic ape theory (AAT) than to illustrate the problems in the belief that humans and apes, orangutans and, the latest hypothesis, chimps, evolved from some common ape ancestor, which has been the only allowed teaching in science classes for the past century and a half. The reason it effectively helps to illustrate the problems is that relying on this bizarre theory accentuates the differences between humans and their proposed ape-like primate ancestors.[7] A new book by Dr. Peter Rhys-Evans outlines the fossil evidence and other considerations supporting the controversial aquatic ape hypothesis. Rhys-Evans describes the standard view:

[For] the past 150 years, scientists and laypeople alike have accepted a “savanna” scenario of human evolution. The theory, primarily based on fossil evidence, suggests that because our ancestral ape family members were living in the trees of East African forests, and because we humans live on terra firma, our primate ancestors simply came down from the trees onto the grasslands and stood upright to see farther over the vegetation, increasing their efficiency as hunter-gatherers.[8]

Rhys-Evans believes the standard view emerged from a paucity of fossils. He says, the reason the “savanna theory of human evolution became ingrained in anthropological dogma” was because the only evidence for human evolution in the 1800s was a few Neanderthal fossils and science then “had very little knowledge of genetics and evolutionary changes.”[9] As a result, the savanna theory became ingrained in tradition, not because of the evidence but because of habit. Dr. Rhys-Evans argues that once this view became entrenched, it “has remained the established explanation of early hominin evolution.”[10]

Dr. Rhys-Evans is an otolaryngologist (an ears-nose-throat doctor) in London. He covers an area of his expertise in his papers. His specialty regards bony swellings called exostoses “grow in the deep part of the external ear canal. We can see them quite easily when inspecting the ear.”[11] The most logical explanation for these growths, he argues, is that they are an adaptation to regular water immersion, protecting the thin tympanic membrane (eardrum) from the water pressure, which can be significant, especially when deep sea diving, and are very rarely seen in people who do not regularly swim. Because they are frequently seen in dedicated surfers, they are known colloquially as “Surfer’s Ear.”

Exostoses in ear canal.

The adaptations of mammalian hearing mechanisms differ in aquatic, terrestrial and semi-aquatic mammals, which their supporters believe is why the aquatic theory explains why humans bear similarities to semi-aquatic mammals like seals, all of which have mechanisms to narrow the ear canal from long term exposure to water.[12] In a recent evaluation of close to two dozen Neanderthal skulls (dated one to two million Darwin Years old), researchers have now found evidence of the features in human skulls. This finding actually better supports, not the aquatic ape origin, but the modern view that Neanderthals were just another human people group that were adapted to very cold weather.[13]

Problems with the Semi-Aquatic Theory

The first problem with the semi-aquatic theory concerns those benign growths of bone, called exostoses, that Rhys-Evans considers evidence for the theory: the way the exostoses grow, and how they narrow the ear canal. Water alone does not form these; significant long-term exposure to wind and cold can also do it.[14] These structures better support an alternate view that early humans adapted not in some semi-aquatic period but in a mini-ice age. That matches proposals for the Neanderthal’s early life in Europe. Furthermore, by comparing other aspects of anatomy and physiology of the skull, ear, nose and throat area in humans and other primates, one can find several other differences besides bony ear exostoses. These include swellings that are not seen in other terrestrial animals, although other semi-aquatic mammals have alternative mechanisms to close off or narrow the ear canal when swimming or diving. Another argument against the aquatic-human evolution theory concerns genetics. Genetic differences between those that have the narrowing mechanism likely play only a minor role in the development of this trait. Cold and water exposure are the main causative factors, not genetics.[15] As such, they are not heritable traits caused by genetic mutations and natural selection.

The Good Side of Exostoses

The view that exostoses are designed—not evolved—is supported by several factors. They are usually bilateral, for instance, and only grow when stimulated by the environment at 2 or 3 specific sites in the deep part of the ear canal near the delicate tympanic membrane. They grow nowhere else in the body, not even in other areas that may be exposed to water. They emerge from the bone growth plates that also form the ossicles in the middle ear (malleus, incus and stapes) that transfer sound energy from the tympanic membrane to the inner ear.

The purpose of the exostoses should be obvious: namely, to protect the delicate eardrum during swimming and diving. The protection mechanism narrows the ear canal to reduce the pressure on the thin, delicate eardrum which is prone to rupture. The closure is either a partial or a (temporarily) complete closing of the ear canal when under water.

Evidence of exostoses have also been found in the ear canals of early hominin skulls which Rhys-Evans claims is evidence of man’s evolutionary aquatic past.[16] This condition can also be found in certain people groups.[17] Actually, constant exposure to water stimulates the development of exostoses, so this is an environmental, not genetic, response. They can eventually close off the ear canal, causing occlusion which can lead to substantial hearing loss. That is why ear protection should be worn by those who spend a great deal of time in water, such as those who surf frequently,[18] in order to prevent the ear canal from constricting excessively, sometimes to the point of complete blockage.

Summary

Since the design view is now unacceptable to the secular academic community (thanks to the Darwinian revolution), a naturalistic evolutionary explanation is always sought, whether or not the evidence supports it. Evolutionists feel obliged to explain this delicate eardrum protection mechanism by imagining an evolutionary story: namely, an aquatic phase in early hominin evolution during which a number of unique features developed that are not seen in any other primate, nor even in any other terrestrial mammal. What has been found is actually yet another design feature that separates humans from putative ape-like ancestors. When a new structure is found, a better question would be, “What is this there for?” instead of “How did this evolve?”

References

[1] Rhys-Evans, P.H. and Cameron, M., Aural exostoses (surfer’s ear) provide vital fossil evidence of an aquatic phase in Man’s early evolution, Annals of The Royal College of Surgeons of England 99(8):594–601, November 2017.
[2] Rhys-Evans, P.H. and Cameron, M., Surfer’s Ear (Aural Exostoses) Provides Hard Evidence of Man’s Aquatic Past, Human Evolution 29(1-3):75-90, 8-10 May 2013.
[3] Hardy, A.  Was man more aquatic in the past? New Scientist 7(174):642–645, 17 March 1960.
[4] Morris, Desmond.  The Naked Ape: A Zoologist’s Study of the Human Animal, p. 29,New York, NY: Random House, 1967.
[5] Rhys-Evans, P.H., A recent book outlines fossil evidence supporting the controversial hypothesis, April 2020, https://www.the-scientist.com/reading-frames/did-human-evolution-include-a-semi-aquatic-phase–67306.
[6]  Rhys-Evans, P.H. The paranasal sinuses and other enigmas: an aquatic evolutionary theory. The Journal of Laryngology & Otology, 106(3):214-225, March 1992.
[7] Bergman, J. “Aquatic Ape Theory: Challenge to the Orthodox Theory of Human Evolution,” Journal of Creation, 21(1):111-118 2007.
[8] Rhys-Evans, P.H., Did Human Evolution Include a Semi-Aquatic Phase?, The Scientist, 1 April 2020, https://www.the-scientist.com/reading-frames/did-human-evolution-include-a-semi-aquatic-phase–67306.
[9]  Rhys-Evans, P.H.,2020.
[10]  Rhys-Evans, P.H, 2020.
[11] In Chapter 11 of Rhys-Evans, P.H., The Waterside Ape: An Alternative Account of Human Evolution, CRC Press, 29 July 2019. Also available at https://www.the-scientist.com/reading-frames/book-excerpt-from-the-waterside-ape-67360.
[12] Villotte, S., and Knüsel, C.J., External auditory exostoses and prehistoric aquatic resource procurement. Journal of Archaeological Science: Reports,6(4):633–636, 2016.
[13] Trinkaus, E. and Wu, X-J., External auditory exostoses in the Xuchang and Xujiayao human remains: Patterns and implications among eastern Eurasian Middle and Late Pleistocene crania. PLOS One, 12 December 2017.  https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0189390.
[14] Kroon, D., et al., Surfer’s Ear: External Auditory Exostoses are More Prevalent in Cold Water Surfers.
Otolaryngology–Head and Neck Surgery, 26(5):499-504, 2002.
[15]  Kroon, D., et al., 2002.
[16] Rhys-Evans, P. H. and Cameron, M., Surfer’s Ear (Aural Exostoses) Provides Hard Evidence of Man’s Aquatic Past. Human Evolution, 29(1-3):75-90, 8-10 May 2013.
[17] Hrdlicka, A. Ear Exostoses, Washington, D.C.: Smithsonian Institute, 1935.
[18] Exostosis aka Surfer’s Ear. California Ear Institute. https://www.californiaearinstitute.com/ear-disorders-exostosis-california-ear-institute-bay-area.php.

Dr. Jerry Bergman has taught biology, genetics, chemistry, biochemistry, anthropology, geology, and microbiology for over 40 years at several colleges and universities including Bowling Green State University, Medical College of Ohio where he was a research associate in experimental pathology, and The University of Toledo. He is a graduate of the Medical College of Ohio, Wayne State University in Detroit, the University of Toledo, and Bowling Green State University. He has over 1,300 publications in 12 languages and 40 books and monographs. His books and textbooks that include chapters that he authored are in over 1,500 college libraries in 27 countries. So far over 80,000 copies of the 40 books and monographs that he has authored or co-authored are in print. For more articles by Dr Bergman, see his Author Profile.