Fossil hominid skull display at the Museum of Osteology By Sklmsta (Own work) [CC0], via Wikimedia Commons
Is it a new human species or just a variant of one already known? Tabitha M. Powledge discusses questions raised by the discovery of 1,550 hominin fossil bones from at least 15 individuals entombed, maybe intentionally, in South Africa: "Many are calling H. naledi a new human ancestor, including the project’s head guy, Lee Berger. But whether these people were actually our forebears or only our cousins is not at all clear. Knowing when they lived would be illuminating."