Did humans come from the seas instead of the trees?
Scientists, academics and medics will gather in London to discuss a
topic that has been virtually unmentionable in academic circles for
decades: are humans descended from "aquatic apes" that spent more time
swimming than dragging their knuckles on the ground?
The last time this question was asked, at a conference in 1992, there
was much scoffing and ridicule. Other academics sneered and Bernard
Levin wrote a full-page article lampooning the idea.
This week's conference, Human Evolution Past, Present and Future -
Anthropological, Medical and Nutritional Considerations, at the Grange
St Paul's Hotel, has also already been the subject of much derision.
Followers of the conventional and overwhelmingly accepted belief that
our ancestors were very much land-based are launching a parody campaign
online to argue we evolved from "space monkeys". Most scientists will
openly scoff at the idea of us deriving from water-bound primates.
But, perhaps emboldened by the presence of Sir David Attenborough -
who was booked to attend the conference for one session but asked at the
last minute if he could attend both days - the aquatic ape theorists are
The conference is chaired by Professor Rhys Evans, an ear, nose and
throat surgeon at the Royal Marsden Hospital, who is candid about the
scope of the conference. "We are trying to discuss the pros and cons of
the theory," he said. "But many of the things which are unique to humans
- such as a descended larynx, walking upright, fat beneath the skin, and
most obviously an extremely large brain - it seems can best be accounted
for as adaptations to extended periods in an aquatic environment." The
original aquatic ape theory, developed by Sir Alister Hardy and made
public in 1960, posited that a population of early humans, or hominoids,
was isolated during tectonic upheaval in a flooded forest environment,
similar to that of parts of the Amazon. Our ancestors, it was argued,
either adapted to water - and climbing in trees - or died out. Over many
generations, mutations that made swimming and diving easier reproduced
in the population at the expense of the more traditional, water-averse
Modern-day apes do not like water. In zoos all around the world, apes
are contained by moats of water. Even wadeable moats are sufficient: if
you drop a baby orangutan into water, it sinks like a stone. A human
baby, however, will close its larynx and automatically paddle its arms
and legs, giving you a few precious seconds to retrieve it.
The aquatic ape theory would explain this ability - unlike the
traditional savannah theory of human evolution. Widely accepted wisdom
states that when humans came out of the woods and on to the savannah,
walking upright gave them an increased field of vision and freed up
hands to use tools.
Bipedalsim also exposed less of the human body to the harsh sun and
humans shed hair and increased sweat production to cope with the heat.
But, the aquatic ape proponents point out, deer and antelope kept
their fur and their quadrapedal ways on the savannah. Our copious salty
sweat production, and water consumption requirements, they argue, are
far more indicative of life in the water. And lions co-operate in
hunting without evolving significantly larger brains than other cats.
The key ingredients for growing a large brain, according to Professor
Michael Crawford, from Imperial College London, are found in fish. "DHA,
or Docosahexaenoic Acid, is essential for developing brain tissue, and
in order for our brains to grow to the size we have now, our ancestors
must have had to eat a lot of fish."
This would have taken place over many hundreds of thousands if not
millions of years, and is part of the reason that the aquatic ape theory
has evolved since its last incarnation, into, tentatively, the waterside
"Molluscs, crabs and snails would be available in abundance in
coastal regions, flooded or swamp forests, lagoons and wetlands,"
Professor Evans said. "Such lifestyles, climbing and hanging vertically,
grasping branches above the water, wading on two legs, floating
vertically collecting foods amid floating vegetation - might help
explain hominoid body enlargement, tail loss, vertical spine, dorsal
shoulder blades, wide thorax and pelvis, great ape tool use and
thickening of enamel."
So waterside theorists are now proposing a prolonged exposure and
adaptation towards coastal living, stretching over several million
years. They argue that fossil evidence seems to back this up.
- The Independent