For many years, it has assumed that our ancestors began walking
upright as a response to savannah encroaching on shrinking
rainforests in northeast Africa. The theory claimed that human
ancestors began walking to get around as there were fewer trees
to swing from and walking on two legs enabled them to see
predators and prey further afield, according to the Daily Mail.
But now a new analysis of the past 12million years' of
vegetation change in north-east Africa has raised question on
the long-held beliefs. about the world in which our ancestors
took shape - and, by extension, the impact it had on them It
found that while the shift to bipedalism seems to have occurred
somewhere between 4million and 6million years ago, rainforests
had been replaced by grasslands and seasonally dry forests some
time before 12million years ago. Not only that, the tropical
grasses and shrubs of the modern African savannah began to
dominate the landscape earlier than thought, replacing other
kinds of grasses better suited to a wett