The human family tree just got a little bigger. The discovery of a new human species was announced earlier today by the National Geographic Society, South Africa's University of the Witwatersrand and the South African National Research Foundation.
The new species,
Homo naledi, was found in a cave known as the Rising Star in the Cradle of Humankind World Heritage Site, about 50km northwest of Johannesburg. "Naledi” means “star” in Sesotho, a local South African language. The initial discovery was made in 2013. The discovery, consisting of about 1,150 fossil elements, was made about 90m from the cave entrance, down an incredibly narrow chute. The two expeditions that discovered and recovered the fossils were led by Lee Berger, research professor in the Evolutionary Studies Institute at the University of the Witwatersrand and a National Geographic Explorer-in-Residence. The full story will be available in the October issue of
National Geographic Magazine; for more details on the expedition, click
here.
So what do we know about our new relative? For starters, the homo naledihas some human features and looks like a primitive member of the genus. John Hawks of the University of Wisconsin-Madison, a senior author on the paper describing the new species, says, "H. naledi had a tiny brain, about the size of an average orange (about 500 cubic centimeters), perched atop a very slender body." On average, the species was about 5ft-tall and weighed around 45kgs. H. naledi's teeth resemble those of the earliest-known members of our genus, while the shoulders resemble those of an ape. Curved fingers suggest climbing capabilities. Its feet, however, are just like ours.
The braincase of a composite male skull of H. naledi measures just 560 cubic centimeters in volume — less than half that of the modern human skull pictured behind it. The fossils were recovered from the Rising Star cave in South Africa by a team led by National Geographic Explorer-in-Residence Lee Berger of the University of the Witwatersrand. The find was announced by the University of the Witwatersrand, the National Geographic Society and the South African National Research Foundation and published in the journal eLife. Art: Stefan Fichtel. Sources: Lee Berger and Peter Schmid, Wits; John Hawks, University of Wisconsin-Madison/National Geographic
A composite skeleton of H. naledi is surrounded by some of the hundreds of other fossil elements recovered from the Dinaledi Chamber in the Rising Star cave in South Africa. The expedition team was led by National Geographic Explorer-in-Residence Lee Berger of the University of the Witwatersrand. The find was announced by the University of the Witwatersrand, the National Geographic Society and the South African National Research Foundation and published in the journal eLife. Photo by Robert Clark/National Geographic; Source: Lee Berger, Wits, photographed at Evolutionary Studies Institute
Another interesting fact about the new species is that it exhibited behaviours previously thought to be unique to humans. The fossils that were found — of children, adults and the elderly — were discovered in a chamber isolated from all other chambers. The bones are virtually untouched by carnivores and scavengers, suggesting that these bodies were intentionally disposed off in this specific room.
Lee Berger’s daughter, Megan, acting as a safety caver on the expedition, and underground exploration team member Rick Hunter navigate the narrow chutes leading to the Dinaledi Chamber of the Rising Star cave in South Africa where fossil elements belonging to H. naledi, a new species of human relative, were discovered. The find was announced by the University of the Witwatersrand, the National Geographic Society and the South African National Research Foundation and published in the journal eLife. Photo by Robert Clark/National Geographic
So remote and isolated was this chamber that the expedition had to bring in people of a certain physical build just to fit down the chute to the room. The 7-inch-wide cave opening meant that only a handful of really skinny and knowlegable scientists and cavers could retrieve the bones. These team members were selected from a global pool, after a call for applicants went out on social media. In the initial expedition, over a period of 21 days, more than 60 cavers and scientists worked to remove the bones.
