BOB HIRSHON (host):
Non-linear evolution. I’m Bob Hirshon and this is Science Update.
The evolution of hominin body size didn’t really follow a straight line like the classic image leading from a stooped ape to an upright human. This according to a study in the journal Royal Society Open Science. University of Cambridge researcher Manuel Will says gains in height and mass actually occurred in fits and starts, likely due to environmental factors. Will’s team analyzed 300 hominin specimens dating back 4 million years.
MANUEL WILL (University of Cambridge):
The evolution of body mass and stature followed different routes in our genus homo, and we found a sole increase in our stature at about 1.5 million years before today, only followed by a pulse in our body weight a million years later.
But Will says some of our now-extinct relatives became smaller, as did modern humans compared to their Pleistocene ancestors. I’m Bob Hirshon, for AAAS, the science society.
Story by Susanne Bard