Human ancestor Lucy died after falling from a tree

​New York: Lucy -- the common name accorded to the very famous fossilised remains of a human ancestor -- probably died after falling from a tree, according to a new study.

Lucy, a 3.18-million-year-old specimen of Australopithecus afarensis or 'southern ape of Afar' is among the oldest, most complete skeletons of any adult, erect-walking human ancestor and was discovered in 1974.

"It is ironic that the fossil at the centre of a debate about the role of arborealism in human evolution likely died from injuries suffered from a fall out of a tree," said John Kappelman, Professor at University of Texas in the study published in the journal Nature.

Kappelman and his teammates carefully scanned all of her 40 per cent complete skeleton and noticed that the end of the right humerus was fractured in a manner not normally seen in fossils, preserving a series of sharp, clean breaks with tiny bone fragments and slivers still in place.

"This compressive fracture results when the hand hits the ground during a fall, impacting the elements of the shoulder against one another to create a unique signature on the humerus," Kappelman added.

For the study, Kappelman consulted Stephen Pearce, an orthopedic surgeon at Austin Bone and Joint Clinic, using a modern human-scale, 3-D printed model of Lucy.