Because we're dealing with events from a unknowably distant period in Earth's history, all we can do is make informed conjecture based upon fossil evidence. Our knowledge of man's development is far from complete, and certain behavioral and physical traits still require explanation. Over the decades, various theories invariably come forward to fill these gaps. Some are carefully considered and firmly based upon observation of available data. Others are decidedly strange. The Aquatic Ape Hypothesis, which holds that modern man evolved from an amphibious hominid, belongs firmly in the latter category.
Here's the skinny: the idea first surfaced in 1930, when a British marine biologist named Alistair Hardy reasoned that man's ancestors were shoved from the trees by our competitive ape cousins and these proto-humans took to the shores to feed upon the shellfish. Eventually they adapted to their watery environment, and the vestiges of these adaptations can still be seen in modern humans. Not yet a credentialed scientist, Hardy was apprehensive about divulging his theory to the world and waited until 1960, in which he detailed his unique hypothesis to a meeting of British Sub-Aqua Club, subsequently publishing his lecture in the pages of New Scientist magazine.
The idea was immediately controversial. However, Hardy's theory did have its proponents, one being BBC television screen-writer Elaine Morgan. Morgan was convinced that the accepted theories about humanity's early days were born out of a male-dominated scientific world and failed to answer crucial questions because they were inherently sexist. In 1967, she read about Hardy's theory in its brief mention in The Naked Ape by Desmond Norris. Morgan was taken with the idea and became the theory's principle advocate.
Morgan asserts that the Aquatic Ape Hypothesis offers explanations for man's upright posture and general lack of hair, among other traits and condemns the paleontologist community for narrow-mindedness and conservatism. Still, the hypothesis hasn't won any major interest in the past forty years among serious scientists, primarily due to the crucial lack of supporting evidence. The skeletal remains of these water-loving ancestors were apparently carried off by the waves, as zero fossils have ever been discovered that corroborate with the theory. Additionally (and this will come as no surprise to anyone) modern aquatic and semi-aquatic mammals are remarkably different from humans in their design. With our long limbs and non-webbed hands, we make comparatively mediocre swimmers. If we ever had an aquatic stage, we'd look more like dolphins....which is a somewhat terrifying thought.
Elaine Morgan continues to write about the Aquatic Ape subject and deliver lectures at UK universities. We can't help but feel somewhat sad about her long, thankless mission. Frankly, her theory just doesn't hold water.
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