An intense scientific debate has ignited around a quiet but extraordinary family living in rural Turkey – a family with five adults who walk on all fours. Since bipedality has long been considered one of the defining characteristics of modern humans, such a discovery raises fascinating questions about genetics, society and the evolutionary history of our species. Is this the anthropological find of the millennium or simply a unique medical case? "NOVA" sets out to unravel the controversy and meet the individuals who have captured the imagination of scientists around the world in this moving documentary. Watch a preview.
NOVA: Family That Walks On All Fours
!["NOVA's" examination of a family that walks on all fours (pictured above) raises fascinating questions about genetics, society and the evolutionary history of our species.](https://cdn.kpbs.org/dims4/default/7e45808/2147483647/strip/true/crop/567x349+27+0/resize/880x542!/quality/90/?url=http%3A%2F%2Fkpbs-brightspot.s3.us-west-2.amazonaws.com%2Fimg%2Fphotos%2F2009%2F10%2F27%2Fnova-family-all4s.jpg)
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