November 21, 2017

The Advocate's Toolbox

Meet “Homo naledi” | A Fascinating Discovery Surfaces

 

EH_MarcAaronson_CTS_perm2015I hope you were as transfixed as I was by the announcement of the discovery of Homo naledi. The discovery itself is only the beginning; the great news about this remarkable find is that it throws the science of human origins wide open—and invites generations of new scientists to join in the hunt—and the conversation—about who we are and where we came from.

In case you missed the excitement: two cavers working with Dr. Lee Berger outside of Johannesburg, South Africa, in an area referred to as the “Cradle of Humankind,” stumbled upon a previously unexplored chamber in the fossil-rich Rising Star Cave system. They noticed some bones on the ground, took grainy pictures, and showed them to Berger, who sent his 15-year-old son, Matthew, back through the tight passage to take more photos. Mathew—whose discovery of a fossil in 2008 led Berger to find Australopithecus sediba (which Berger and I wrote about in The Skull in the Rock, National Geographic, 2012)—shimmed into the cave and was transfixed. He spent an hour and a half shooting photos of what he was sure were human ancestor fossils. Berger knew that he had to see what was there. He sent out a Facebook query looking for trained paleoanthropologists who were comfortable working in confined spaces, had experience caving, and were “very thin.”  Immediately, Berger received more than 60 responses and selected six “Underground Astronauts”—all women—to go exploring.

The search for bones took place in late 2013 and early 2014. Since then a team of more than 60 scientists has been examining the more than 1500 fragments (from at least 15 individuals) that were recovered. They represent the full age range—babies to elders—of a new and previously unknown species. They were tall, thin, and walked on two feet, and had humanlike hands and feet and tiny, chimplike brains. All of this is fascinating—as is the reason why, for the time being, we cannot date the fossils. (Here’s a good explanation from The Atlantic.)

But the big news is the question why all of these bones (and the cavers say they have only brought up a tiny fraction of what is down there) are in the same spot. There is no evidence that animals dragged them in or chewed on the bones, or that water, wind, or another natural force swept the remains into the cave. There is no evidence of a disaster resulting in a mass death and indeed the layers of bones suggest they were put there over time. The only current and likely explanation is that they were placed there. In other words, some two million years ago (that is what the body type suggests), a creature more chimp than human (and perhaps an ancestor of ours), buried its dead. Before this discovery we had no evidence of burial before, say, 100,000 years ago. As Berger explains, and Frans de Waal, a prominent scientist, echoed in his New York Times opinion piece, “Who Apes Whom?” the line between us and chimps is disappearing.

We have new science, new questions, and a new type of inclusive discovery where Facebook and young people have played central roles. And we have the grand potential to bring it into schools. John S. Mead, a science teacher at the St. Marks School in Dallas, TX, met with Berger this summer and taped a set of video interviews with the scientist. If you want to share this discovery with your students—Berger; John Hawks of the University of Wisconsin; Matthew Berger; Megan Berger (Lee’s daughter, who spent more time in the cave than her brother); and many of the Underground Astronauts and cavers are represented in the videos.

What more could we possibly want–the most dramatic discovery shared in the most open manner? The door to the adventure of science has been thrown wide open. Please bring this story to your schools.

 

Extra Helping header

This article was featured in our free Extra Helping enewsletter.
Subscribe today to have more articles like this delivered to you twice a week.

Marc Aronson About Marc Aronson

Marc Aronson is a Rutgers University lecturer in the School of Communication and Information and the author of many notable nonfiction titles for children and young adults including, The Skull in the Rock, winner of the 2013 Subaru Prize from the American Association for the Advancement of Science. His book The Griffin and the Scientist (with Adrienne Mayor) will be published in April 2014. He was the first recipient of the Robert F. Sibert medal from the American Library Association for excellence in nonfiction writing for youth.

Share

Comments

  1. Marc – so glad you are writing about this – the day everything was announced my email blow up with comments as we have several teachers using The Skull in the Rock. One history teacher reads it with her whole 9th Grade. It has Science, History, Mathematics, and Discovery all rolled into one great book.
    Another resource for everyone to think about using is the NOVA Special that just aired about this
    NOVA: Dawn of Humanity – this has school year rights. Our BOCES Media Center received over 65 requests for off-air copies to use this school year.
    http://www.pbs.org/wgbh/nova/evolution/dawn-of-humanity.html
    Hope this motivates everyone to get students involved with Science, History, and Mathematics – all together!
    Sue Bartle

  2. marc aronson says:

    thanks for mentioning the NOVA special, it is available online, or at least it was, and tells the whole story.

  3. Thanks for this. A great discovery & excavation, but from a comparative viewpoint, Homo or Australopithecus naledi is no mystery (in fact predicted, see Trends Ecol.Evol.17:212-7, 2002, google: aquarboreal).
    It was no burial, no ancestor, no runner: prof.Berger’s interpretations are anthropocentric: they were bonobo-like forest-swamp or wetland waders who collected waterlilies etc. (google: bonobo wading), and died in the swamp (mud-stone indicates stagnant water):
    – The curved hand bones suggest vertical climbing in the branches above the swamps.
    – The long thumbs were less for tool use than for collecting floating herbs and/or for surface-swimming.
    – The broad pelvises (iliac flaring & long femoral necks) were for sideward movements of the legs (femoral abduction): for climbing and/or swimming rather than for running.
    – The flat humanlike feet are more flamingo- (plantigrade wader) than ostrich-like (digitigrade runner).
    Lowland gorillas often wade on 2 legs in forest swamps for papyrus sedges, frogbit etc. (google: gorilla bai), but naledi apparently exploited this special niche habitually: no wonder there were no or few other macro-fauna near the naledi fossils. It was no deliberate burial (small brains): when they died, their bodies sank in the mud, and afterwards later the underground eroded to become a cave system (cf geological uplift of S-Africa).
    If we go back in time towards the Homo/Pan last common ancestor, Homo shows more Pan-like features, and Pan shows more Homo-like features: what is “primitive” in Homo might sometimes be “derived” in Pan, and vice versa.
    IOW, naledi, in spite of its few primitive-Homo-like features (e.g. prenatal chimps have more humanlike feet), was more likely a close relative of Pan than of Homo (google: researchGate marc verhaegen).