    • The Observer,   • Jump to comments () Female western
lowland gorilla A female western lowland gorilla walks through a
river. Some scientists believe our ancestors lived an aquatic
lifestyle. Photograph: Getty    "Humans are very different from
other apes," said Peter Rhys Evans, an organiser of Human
Evolution: Past, Present and Future. "We lack fur, walk upright,
have big brains and subcutaneous fat and have a descended
larynx, a feature common among aquatic animals but not apes."
"Humans have particularly large sinuses, spaces in the skull
between our cheeks, noses and foreheads," he added. "But why do
we have empty spaces in our heads? It makes no sense until we
consider the evolutionary perspective. Then it becomes clear:
our sinuses acted as buoyancy aids that helped keep our heads
above water."   "I think that wading in a watery environment is
as good an explanation, at the moment, for our upright gait as
any other theory for human bipedalism," said Professor Chris
Stringer of the Natural Hist