The family that walks on all fours
...Scientists now say they don’t move like quadrupedal primates
The five brothers and sisters, aged between 18 and 34 and from a village in Hatay Province, south Turkey, have fascinated scientists across the world since they were first discovered in 2005.
They get around by
‘bear crawling’ on their feet and palms - and can only stand upright for a short time, with both knees and head flexed.
Earlier theories claimed the Ulas family’s quadrupedal gait was similar to the movement of primates, suggesting ‘a backwards stage in human evolution’.
But now, American scientists have concluded that the siblings’ walk is an adaptation to an unforeseen and rare disorder. In a report published in
the researchers said the family moves laterally - unlike primates, who walk in a diagonal sequence, repeatedly putting a hand on one side and a foot on the other.
They claimed the siblings’ walk is, in fact, a byproduct of a hereditary condition that causes cerebellar hypoplasia, complicating their sense of balance.
To adapt to this condition, the family have developed quadrupedalism, they said.
‘I was determined to set the record straight, because these erroneous claims about the nature and cause of the quadrupedalism have been published over and over again, without any actual analysis of the biomechanics of their gait, and by researchers who are not experts in primate locomotion,’ lead researcher Liza Shapiro, of the University of Texas, told The Washington Post.
‘We have shown
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