Are We Descended from Mermaids? July 4, 2012
The
Littoral People
Unlike the portrayal on Animal Channel’s special fictional
documentary, “Mermaids: the Body Found”, on Memorial Day weekend, we never
really turned into mermaids. We only
made it about a quarter of the way. We
really didn’t need to go all the way to aquaticness. We were shore-dwellers, living off the “fat
of the land”, and especially the fat of the sea, in this special ecological niche. It was the high level of omega-3 fatty acids
and cholesterol in seafood that gave our brains the fuel to expand and grow.
Littoral
apes become literary apes
Unlike your dog or cat, humans occasionally have the
misfortune of choking to death. If we
choke on a pretzel, it can stop our breathing.
This is because our breathing tube (trachea) and our eating tube
(esophagus) intersect. In other (land) animals they are separate. This was an
evolutionary adaptation for the ability to hold our breath while diving
underwater, a trait we share with other diving mammals, like whales and
dolphins. Breath control is a precondition
for speech. Dolphins, whales and seals can obviously hold their breath, for a
long time, in order to dive and swim underwater. Perhaps this is what allowed dolphins and
whales to develop their own extensive vocal communication systems, like whale
songs. John C Lilly was one of the first
scientists to study dolphin communication.
He later did interesting studies on human consciousness and wrote books
like Programming and Metaprogramming in the Human Biocomputer (1972).
Chimps may learn sign language, but they are incapable of ever learning
to speak.
What
would Semi-Mermaids eat?
What would shore-dwelling people eat? Food from the sea, as well as food from land
near the shore line, starting with things that were easy to catch, like
shellfish, seaweed, eggs of seabirds, and fruits and berries growing along the
shore, like blueberries and beach plums.
This would have been an extremely healthy diet, providing everything
needed for a growing brain.
Why
We Walk Upright
Wading out to sea to look for food, while keeping our heads
above water, long-legged creatures have an advantage. Our evolutionary path gave priority to long
straight legs, with a little webbing between our fingers and toes. For
swimmers, heavy, wet fur sure is a drag, so we became the Naked Ape. This is certainly a more reasonable
explanation that all the fanciful stories trying to justify the Savannah
theory. We retained the hair on our
head, to protect the brain from overheating in the sun. Elaine Morgan has speculated that the reason
women tend to have long hair on their head is to give their floating babies
something to hold onto.
Fat
Babies Float
Human babies are much fatter at birth than baby monkeys and
other apes. Why should this be? It is a great caloric expense to pregnant
mothers to produce all that fat, and requires an exceedingly rich, high fat
diet. Also it would be burdensome to have to carry that fat heavy baby
around. The simple answer is: fat babies float. Fat is less dense than water. Fat people float easily, while skinny, bony
people have trouble staying afloat. If
our ancestors were spending a lot of time in the water, fat babies would be
more likely to survive. New born babies
instinctively hold their breath and paddle when placed in the water, learning
to swim before they can walk. If not
exposed to water, they lose this instinct after a few months. Humans of all ages have a layer of
subcutaneous fat (of varying thickness), a trait they share with marine
mammals, but not other primates. This
fat layer serves as insulation to retain body heat in the water, and also
increases buoyancy.
Are
We Cousins to Dolphins?
Eventually, with our new tall, hairless body and big brain,
we moved from the shoreline to recolonize the land, becoming hunters and
gatherers on the African Savannah.
Perhaps some of us stayed in the sea and eventually became perfectly
adapted to it, like the dolphins. Dolphins,
like whales, have evolved from land animals.
No one knows what the land ancestor was like. Maybe it was us! Scientists at Texas A&M
were surprised to discover many similarities between dolphin and human genomes.
