The fossil bones illustrated in this photo are two of four apparently cut-marked bones recovered from DIK-55, specifically from the Sidi Hakoma Member of the Hadar Formation. The Sidi Hakoma member is reckoned to have been laid down between 3.42 and 3.24 million years ago.
The top fossil in the photograph is the right rib of a large ungulate, probably about cow-sized. Two parallel marks (Mark A) are v-shaped in cross-section with internal micro-striations. Mark B is an obliquely oriented mark that apparently shows a stone tool shaved off the bone surface. Mark C is an indentation, which investigators have described as a hammerstone percussion mark.
The bottom fossil is the shaft of a femur from a goat-sized juvenile animal. Mark D is a cluster of striations exhibiting crushing of the bone surface. Marks E and H have shaved places. The Nature article includes close-up photos and scanning electron microscope images of each of the cutmarks they encountered.
Sources and Further Information
- Selam (the "Dikika Baby", A. afarensis discovered by Alemseleged et al.)
- Lucy (A. afarensis discovered by Donald Johansen)
- Australopithecus
Domínguez-Rodrigo M, Pickering TR, and Bunn HT. 2012. Experimental study of cut marks made with rocks unmodified by human flaking and its bearing on claims of ~3.4-million-year-old butchery evidence from Dikika, Ethiopia. Journal of Archaeological Science 39(2):205-214.
McPherron SP, Alemseged Z, Marean CW, Wynn JG, Reed D, Geraads D, Bobe R, and Bearat HA. 2010. Evidence for stone-tool-assisted consumption of animal tissues before 3.39 million years ago at Dikika, Ethiopia. Nature 466:857-860.
