In August 2019, Dr Marine Cazenave of the Sefako Makgatho Health Sciences University branch of the Bakeng se Afrika project had the opportunity to present her ongoing research at the East African Association of Paleoanthropology and Paleontology Seventh Biennal Conference held at the National Museums of Kenya in Nairobi.
This conference provided the ideal opportunity to introduce the possibilities of paleoanthropological research in the Bakeng se Afrika project. The Bakeng se Afrika team is proud to share the abstract of the talk, entitled "The odontoskeletal maturational pattern of P. robustus compared to the evidence from A. sediba and H. erectus (KNM-WT 15000)" on our blog:
"The taxon Paranthropus robustus was established in 1938 by R. Broom following the discovery of the partial cranium and associated mandible TM 1517 at Kromdraai B, South Africa. Shortly after, Broom reported the discovery, nearby and from the same matrix, of a distal humerus (TM 1517g), a proximal ulna (TM 1517e), and a distal hallucial phalanx (TM 1517k).
Although the P. robustus holotype represents a dentally immature individual, no analysis has documented the possible presence of any remnant of still growing or recently fused bone on the likely associated three postcranial elements, but only the evidence that the humerus and the ulna articulate.
In the hominin fossil record, there are few craniodentally immature specimens unambiguously associated to postcranial remains, an essential condition for assessing the taxon-specific maturational patterns. Importantly, information on such pattern is still unreported for P. robustus. Using microCT scanning, we thus performed a study aimed at characterizing the degree of epiphyseal closure of the three postcranial remains from Kromdraai B.
In TM 1517, the M2 roots show not fully closed apices, while the M3 roots only reached 50-75% of their total length, which in extant humans corresponds to a developmental stage of 16.5±3 years. High-resolution 3D-based imaging shows that the distal humerus was likely completely fused, while the ulna and, to a lesser extent, the hallucial phalanx still display a subtle remnant of growing bone.
Our results thus support the attribution of the cranial and three postcranial remains to the same individual representing the P. robustus type specimen. They also indicate that TM 1517 more closely fits the Pan and, to a lesser extent, the human male maturational pattern, in line with the evidence observed for Australopithecus sediba and Homo erectus from Nariokotome. Nonetheless, the still uncertain sex attribution of TM 1517 represents an additional complicating factor."
We are happy to welcome Dr Cazenave home, and proud to have her on the team.
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