Fossil hominins were first discovered in the Dinaledi Chamber of the Rising Star Cave system in South Africa during an expedition led by Lee Berger beginning October 2013. In November 2013 and March 2014, over 1550 specimens from at least 15 Homo naledi individuals were recovered from this site. This excavation remains the largest collection of a single hominin species that has been found in Africa. Rick Hunter and Steven Tucker found an additional 133 Homo naledi specimens in the nearby Lesedi Chamber in 2013, representing at least another 3 individuals – two adults and a juvenile. In 2017, the Homo naledi fossils were dated to between 335,000 and 236,000 years ago.
We don’t know everything about our early ancestors—but we keep learning more! Paleoanthropologists are constantly in the field, excavating new areas with ground-breaking technology, and continually filling in some of the gaps in understanding human evolution.
Below are some of the still unanswered questions about Homo naledi that may be answered with future discoveries:
1. How is Homo naledi related to other Homo species?
2. The hand morphology of Homo naledi suggests its use in climbing trees, whereas studies of the Homo naledi foot indicate adaptation to a terrestrial lifestyle. Why is this so? How did Homo naledi move and in what kinds of habitats?
3. Homo naledi appears to have lived near the same time as early ancestors of modern humans. Why did Homo naledi have a mixture of ancient and modern anatomical characteristics?
4. What was the diet of Homo naledi?
5. No tools have yet been found in the two cave chambers; what kinds of tools did Homo naledi make and use?
6. Were the individuals found in the Dinaledi and Lesedi chambers deliberately placed there? If so, was Homo naledi itself or another species responsible for this activity?
Berger, L.R., Hawks, J., de Ruiter, D.J., Churchill, S.E., Schmid, P., Delezene, L.K., Kivell, T.L., Garvin, H.M., Williams, S.A., DeSilva, J.M., Skinner, M.M., Musiba, C.M., Cameron, N., Holliday, T.W., Harcourt-Smith, W., Ackermann, R.R., Bastir, M., Bogin, B., Bolter, D., Brophy, J., Cofran, Z.D., Congdon, K.A., Deane, A.S., Dembo, M., Drapeau, M., Elliott, M.C., Feuerreigel, E.M., Garcia-Martinez, D., Green, D.J., Gurtov, A., Irish, J.D., Kruger, A., Laird, M.F., Marchi, D., Meyer, M.R., Nalla, S., Negash, E.W., Orr, C.M., Racovcic, D., Schroeder, L., Scott, J.E., Throckmorton, Z., Tocheri, M.W., VanSickle, C., Walker, C.S., Wei, P., Zipfel, B. 2015. Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa. eLife 4(e09560).
Other recommended readings:
Dirks, P.H., Berger, L.R., Roberts, E.M., Kramers, J.D., Hawks, J., Randolph-Quinney, P.S., Elliott, M., Musiba, C.M., Churchill, S.E., de Ruiter, D.J., Schmid, P., Backwell, L.R., Belyanin, G.A., Boshoff, P., Hunter, K.L., Feuerriegal, E.M., Gurtov, A., Harrison, J., Hunter, R., Kruger, A., Morris, H., Makhubela, T., Peixotto, B., Tucker, S. 2015. Geological and taphonomic context for the new hominin species Homo naledi from the Dinaledi Chamber, South Africa. eLife 4L e09561.
Kivell, T.L., Deane, A.S., Tocheri, M.W., Orr, C.M., Schmid, P., Hawks, J., Berger, L.R., Churchill, S.E. 2015. The hand of Homo naledi. Nature Communications 6: 8431.
Harcourt-Smith, W.E.H., Throckmorton, Z., Congdon, K.A., Zipfel, B., Deane, A.S., Drapeau, M.S.M., Churchill, S.E., Berger, L.R., DeSilva, J.M. 2015. The foot of Homo naledi. Nature Communications 6: 8432.
Dirks, P.H., Roberts, E.M., Hilbert-Wolf, H., Kramers, J.D., Hawks, J., Dosseto, A., Duval, M., Elliott, M., Evans, M., Grün, R., Hellstrom, J., Herries, A.I., Joannes-Boyau, R., Makhubela, T.V., Placzek, C.J., Robbins, J., Spandler, C., Wiersma, K., Woodhead, J., Berger, L.R. 2017. The age of Homo naledi and associated sediments in the Rising Star Cave, South Africa. eLife 6: e24231.
Hawks, J., Elliott, M., Schmid, P., Churchill, S.E., de Ruiter, D.J., Roberts, E.M., Hilbert-Wolf, H., Garvin, H.M., Williams, S.A., Delezene, L.K., Feuerriegel, E.M., Randolph-Quinney, P., Kivell, T.L., Laird, M.F., Tawane, G., DeSilva, J.M., Bailey, S.E., Brophy, J.K., Meyer, M.R., Skinner, M.M., Tocheri, M.W., VanSickle, C., Walker, C.S., Campbell, T.L., Kuhn, B., Kruger, A., Tucker, S., Gurtov, A., Hlophe, N., Hunter, R., Morris, H., Peixotto, B., Ramalepa, M., van Rooyen, D. Tskioane, M., Boshoff, P., Dirks, P.H., Berger, L.R. 2017. New fossil remains of Homo naledi from the Lesedi Chamber, South Africa. eLife 4: e24232.
Bolter, D.R., Hawks, J., Bogin, B., Cameron, N. 2018. Palaeodemographics of individuals in Dinaledi Chamber using dental remains. South African Journal of Science 114 (1/2), 1-6.
Due to the lack of other animal fossils or tools associated with Homo naledi, very little is known about the ecology and life of this species. Its teeth may provide ultimately offer clues regarding the diet and environment of this southern African species. Its teeth, in fact, differ from other Homo species that lived around the same time. So, it may be that Homo naledi inhabited a distinct environment from that occupied by other Homo species, despite having many other morphological similarities.
The placement of Homo naledi in the evolutionary tree of the genus Homo is currently unresolved. Homo naledi possessed a mixture of traits that are Australopithecus-like (particularly in the pelvis and shoulder) and Homo-like (particularly in the hands and feet, and the size of its brain). Further comparative research is needed in order to learn more about how Homo naledi was related to Homo erectus and other species of the genus Homo.