The evolutionary tree of hominids continues to fill in as, over the decades, more skeletal remains are excavated in Africa, Europe and Asia. But the history of great apes, to which hominids share a recent common ancestor, has yielded far fewer clues.
If hominids, which include Homo sapiens, are the tree, great apes are its roots. Because humans share a common ancestor with the great ape family, finding and analyzing their ancient bones can help us better understand human evolution.
In 2002 in Spain, scientists unearthed an ape-like skeleton nearly 12 million years old, the dawn of the great ape evolution. Since evidence of hominid bipedalism goes back 4 million years, the fossil offered a rare glimpse to the evolutionary big bang of higher primates, which includes gorillas, orangutans, chimpanzees, bonobos and humans.
In an article in the March 2013 Journal of Human Evolution, Ashley Hammond, a Life Sciences Fellow in MU’s Department of Pathology and Anatomical Sciences, co-wrote that the skeleton’s hip suggests the ancient creature walked upright.
Hammond used a tabletop laser scanner attached to a turntable to capture detailed surface images of the fossil, which provided her with a 3-D model to compare the pelvis to the anatomy of today’s apes. She also compared the pelvis’s ilium to an older ape-like species dating back 18 million years. The Spain skeleton’s was wider, more like an ape’s than a monkey’s, and indicated the animal might have had the ability to sometimes walk as a biped. The creature also had flexible wrists like those of higher primates.
“We need to continue fieldwork to identify more fossils and determine how the species are related and how they lived,” Hammond said. “Ultimately, everything is connected.”