Fossil remains of new hominin species Homo naledi discovered in South Africa

Paleontologists have discovered the fossil remains of a new hominin species in a dark cave system in South Africa and published their preliminary results in eLife. The new species has been named Homo naledi, which means “star man” in Sotho, after the Dinaledi Chamber of the Rising Star cave system where it was found. Homo naledi is characterized by a small body and brain size, but it also features several adaptations of the hands and feet that are relatively similar to modern humans. The age of Homo naledi and its position in the phylogenetic tree of hominins is still unresolved, but it is believed to be one of the more primitive ancestors of mankind. So far, an unprecedented 1550 remains of at least 15 individuals of Homo naledi have been unearthed, representing the largest fossil assemblage of a single hominin species ever found in Africa. Given the richness and exceptional preservation state of these fossils, it is speculated that Homo naledi may have been capable of performing primitive burial rites.


Journal references:

Berger, L. R., Hawks, J., de Ruiter, D. J., Churchill, S. E., Schmid, P., Delezene, L. K., … & Zipfel, B. (2015). Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa. eLife4, e09560.

Dirks, P. H., Berger, L. R., Roberts, E. M., Kramers, J. D., Hawks, J., Randolph-Quinney, P. S., … & Tucker, S. (2015). Geological and taphonomic context for the new hominin species Homo naledi from the Dinaledi Chamber, South Africa. eLife4, e09561.

Image: Fossil remains of Homo naledi, the new hominin species discovered in South Africa. Source: Lee Berger, Wikimedia Commons.

Species extinction rates higher than previously thought

According to a new study performed by biologists, the current extinction rates of terrestrial animal and plant species associated with human activities may be up to 10 times higher than previously thought. By using fossil datasets and mathematical models, the scientists were able to estimate new natural background rates of species diversification and extinction. Their results indicate that until now, these background rates are likely to have been overestimated and should be in the order of 0.1 extinction per million species per year, rather than 1 extinction per million species per year. Because current rates of extinction are compared against background levels, these new results have major implications for the apparent impact of mankind on life on Earth: the effects may be even more severe than expected.


Journal reference: De Vos, J. M., Joppa, L. N., Gittleman, J. L., Stephens, P. R., & Pimm, S. L. (2014). Estimating the normal background rate of species extinction. Conservation Biology.

Image: Fossil remains of Archaeopteryx displayed in the Museum für Naturkunde in Berlin, Germany. Source: H. Raab, Wikimedia Commons.