17 The Non-Aquatic Ape: The
Aquatic Ape Theory and the Evolution of Human Drowning and Swimming |
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SUMMARY From an analysis of the evolutionary processes that have led to the features that have diminished humans' adaptation for survival in the water, it appears that from a traditionally biological point of view we are indeed, like the apes, poorly adapted. However, the percentage of humans that actually die from drowning is relatively low - the result of other, counteracting, adaptations namely, our cognitive and manual abilities. A central question of the Aquatic Ape Theory debate, not hitherto addressed, is therefore: did the aquatic ape already possess these abilities, including those of transferring to conspecifics, especially offspring, the necessary knowledge? Indications from comparative morphology, physiology and ethology, and from paleoanthropology, appear to offer a negative answer to this question. The analysis, therefore, does not support the AAT. |
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INTRODUCTION Attempt to test the AAT with data.
MAN AND WATER: THE PARADOX LIFE AND WATER LOSS OF WATER ADAPTATION BUOYANCY Breathing in makes a big difference. BREATHING ASPIRATION, HYPOTHERMIA AND OSMOLARITY Cold water kills as does salt water. |
LOCOMOTION Humans in water for the first time tend to panic. With trial and error this can be avoided and swimming strokes be learned. The plasticity of our behaviour facilitates this as does the accumulation of knowledge and experience, language etc. and our extremely moveable shoulder joints from our arboreal past. HUMAN BEHAVIOUR EVIDENCE FROM THE APES? OCEANIC DESIRES THE AAT AND THE SWIMMING BABIES CONCLUSION |
COUNTER-ARGUMENTS Jan Wind makes some interesting points. I am particularly interested about his assertion that humans and apes share about the same level of incompetence in water. If this were true it would surely strongly argue against the AAH. However Wind did not address the distinctive hydrophobia of chimpanzees and bonobos and make any comparison with humans - particularly infants, which cannot be exposed to any culture or nurture - his main argument. That to me is the biggest weakness in his argument. Human babies are 15% fat, hence relatively buoyant as he admits. There is a very large difference between humans and chimps in this regard and it needs an explanation. The lack of buoyancy in human adults is surprising, but could explain why we have such powerful voluntary control over our breathing. I was also taken by the idea that technology and use of floating aids would clearly, paradoxically make us less well adapted to water. As hominid technology improved over the last 2 my this would probably have been a factor in our swimming abilities and might even explain why we are not much better in water than AAH opponents would like to predict. |