Aquatic Ape Human Ancestor Theory

Aquatic Ape Theory - What is it?

A Brief Summary of AAT - key arguments

A Brief History and Key Proponents of AAT

Current Aquatic Evolution Theories


Alternative theories of human evolution

Wikipedia and the scientific community

. Anatomical Evidence
... Bipedalism
... Birth and babies
... Brain
... Breath control
... Fat
... Fingers, toes and feet
... Furlessness
... Hair and baldness
... Kidneys
... Menopause
... Nose
... Olfactory sense
... Pachyostosis
... Paranasal Sinuses
... Platycephaly
... Sexual features
... Surfer's ear
... Sweating
... Tears
... Underwater vision

. Diet
. Language & Song
. Sleep (USWS)
. Waterside environments
. Sea Gypsies

. Homo erectus - shallow diver

. Fossil evidence
. Paleoecological evidence

A call to scientists...

Recent News and Updates

Books and publications

Videos links



Aquatic Ape Theory or Semi-Aquatic Human Ancestor Theory?

What is it? Controversy Surrounding A Name

The ‘Aquatic Ape Theory’ (AAT) aka ‘Aquatic Ape Hypothesis’ (AAH) has given rise to a great deal of controversy in recent decades, and not only among opponents of the theory. Perhaps it's because the name implies that an early ape-like human ancestor entered the sea millions of years ago, and then walked out of the sea as Homo sapiens millions of years later. This has encouraged opponents of the theory to regard it as a form of 'pseudo-science' and to dismiss the arguments of how water may have played a morphological role in the evolution of the human ancestor, without ever really considering the evidence.

But the majority of AAT advocates today no longer believe that the truth is quite so simplistic. For this reason, most supporters tend to prefer terms such as ‘Waterside Hypotheses of Human Evolution’ (WHHE) or ‘Waterside Hominid Theory' (WHAT) or 'Littoral / Coastal Dispersal Model', in order to move away from the false and often deliberately distorted nonsense arguments that our ancestors were some kind of “mermaid”. The modern arguments in favour of the Aquatic Ape Theory - or however you choose to call it - do not focus on an ape ancestor millions of years ago. Instead they tend to examine the ways in which water has had a profound influence on the evolution of Homo (and Homo ancestors), in various ways over the course of time, and continues to do so, even today.

Poster for the aquatic human

Human Aquatic Adaptations - by Chakazul
Click on the poster to open the full-size pdf version

So what is the Aquatic Ape / Semi-Aquatic Human Ancestor Theory / Hypothesis of Human Evolution?

The basic premise behind the Aquatic Ape Theory, and all its various denominations, basically states that at some period in history, or at various different times in history, water has played a morphological role in the evolution of our human ancestors, leading to many of the major differences between ourselves and the great apes, including, but not limited to: furlessness, bipedalism, subcutaneous fat, a larger brain, language, tears, protruding noses, eccrine sweat cooling, poor sense of smell, floating babies, superior breath-holding abilities, pyramidal kidneys, the ability to learn how to refocus our eyes underwater, etc.

However, there is or has been strong disagreement between proponents of AAT/AAH about 'when', 'where', 'how long for' and 'in what ways' the influence of water has played a role. There is also disagreement about what kind of water: salt water / marine or fresh water: rivers and lakes. This has led to discussion about the applicableness of the current term with some proponents stating that it is not about 'ape' at all, but more about 'Homo', and that it's not just water but more about coasts, that it's not about complete immersion, but more a waterside or coastal existence...

For this reason, and in order to try to reduce the ambiguity we have decided to use the term: (Semi) Aquatic Human Ancestor Theory (AHAT).

Possible aquatic adaptations in human - Arguments for the aquatic ape hypothesis and related water-based models Notes: The diagram demonstrates the arguments proposed in the aquatic ape hypothesis (AAH) and related water-based models (e.g. the shore-based diet model), that swimming, diving, and a semi-aquatic lifestyle may have influenced human evolution, caused numerous adaptations in human morphology, anatomy and physiology. This diagram is a plain description of the hypothesis and does not provide any support nor criticism to the arguments. It must be noted that the points listed are not facts, but hypothetical claims that require further scientific investigations to verify their accuracy, falsifiability, and relevance to human evolution. The possible adaptations are grouped into aspects: swimming, floating, diving, foraging, walking, running, pregnancy, infancy, gender, sex, and a zoom-in of the head and the upper body.

Chakazul - Own work based on: Hardy AC (1960) Was man more aquatic in the past? New Scientist 17 Mar 7 (174): 642-645 Morgan E (1982) The Aquatic Ape. Stein & Day Pub Morgan E (1990) The Scars of Evolution. Souvenir Press Morgan E (1997) The Aquatic Ape Hypothesis. Penguin Roede M, Wind J, Patrick J, Reynolds V (eds.) (1991) Aquatic Ape: Fact or Fiction? Souvenir Press Vaneechoutte M, Kuliukas AV, Verhaegen M (eds.) (2011) Was Man More Aquatic in the Past? Fifty Years After Alister Hardy - Waterside Hypothesis of Human Evolution. Bentham Science Publishers Cunnane SC, Stewart KM (eds.) (2010) Human Brain Evolution: The Influence of Freshwater and Marine Food Resources. Wiley-Blackwell Niemitz C (2010) The evolution of the upright posture and gait – a review and a new synthesis. Die Naturwissenschaften 97 (3): 241-263 Odent M (1996) We are All Water Babies. Celestial Arts Verhaegen M et al.: various publications in Medical Hypotheses (1985, 1987), Nutrition and Health (1993), Ecology Research Progress (2007) [1]

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