We’ve all watched enough true-crime dramas to know that our dental records can do wonders when it comes to telling investigators about our identity, our past, and our demise. Scientific investigators, it seems, are in on the secret, too, with new research coming out all based on the bite of one of the early hominids, Australopithecus sediba. So just what does this early partial biped’s bite tell us?
Australopiths have a long record in early hominid history, dating back 4 million years. A. sediba was, to the best of our scientific knowledge, a bit late to the scene, dating back around 2 million years. The species was discovered in 2008 by son of paleoanthropologist Lee Berger on the Malapa Nature Reserve just north of Johannesburg, South Africa. Berger’s son’s accidental discovery was only the mandible, though. It wasn’t until 2009 that they were able to find the entire remaining portions of the skull, enough to identify it as a juvenile male. In 2010, the team announced their discovery to the public.
Later skeletal remains from the species show the arms, legs, and narrow chest to resemble that of early australopithecines, while tooth trait and a broad lower chest, along with changes to the pelvis to indicate upright walking, are more similar to the genus Homo, which was evolving at about the time A. sediba walked the planet. The importance of this early ancestor has long been argued, as it may well give scientists an evolutionary mark for when the australopiths went from primarily or partial arboreality to a predominantly bipedal walking with shoulders shrugged and arms unswigging, something closer to that of a modern walk.
Now, six years after the species first went public, new research on the jawline of a preserved skull may help place the diets of early hominids as well as later Homo species.
What The Jaw Reveals
Many of the early australopiths had adaptations in the jaws that allowed them to work with food that was difficult to chew or crack open, including a strong bite. A. sediba, while still able to live off of a diet that included bark, was apparently far more limited in its jaw adaptations, new research suggests.
The limited bite force of A. sediba is something that is also found in modern humans, and is suspected to have occurred in earlier Homo species, as well. With A. sediba representing one of the closest relationships in the known evolution of man between early australopiths and later humans, the jawline of this skull gives scientists a lot of new information about how the human bite may have come about.
The discovery also allows science better understanding of the purpose and function of early species adaptations. Understanding the mechanics is one thing, but with that information in hand more work has been done regarding why this species had such a different food processing capability than any other species in the genus, and what that meant for its survival.