Homo Naledi

Paleoanthropology was a field in which the number of professional researchers was greater than the number of fossils to study until the late 1990’s. To find a single finger-bone could make your career. Lee Berger had found two teeth years earlier and was still dining out on them, by his own account. We are now awash in new, largely unexplained hominids, and a good deal of that comes from a “wasted” three years of Berger’s career trying to find new sites using Google Earth, then suddenly finding the obstruction and patiently removing it. A great podcast from The Insight.    It’s long, so I recommend it for a walk or drive.

We have long envisioned human descent as a tree, with some branches dead-ending in no descendants and only the line to homo sapiens sapiens somehow weathering the storm. It is certainly what I was taught in Physical Anthropology 101 in the 1970’s. That was undermined when it became clear that we had interbred with Neandertals, and further so with the discovery of the Denisovans, who turn out to be many and widespread.  Now even Africa is being reexamined because of the new sites, including new species.  The metaphor now is of a braided stream of genetic descent, more like a river delta.

It is changing so fast that I fear this interview with Berger from 2018 may already be out-of-date. It’s fascinating for what the story tells us about scientific research in general, including how to relook at something that others have been looking at for a century, how failure might not be wasted, and how to question your own assumptions.  The adventurous parts are great as well, including sending very thin people along sheer underground cliffs and down impossibly thin shafts in the dark, 40 feet into the earth to study the bones at least fifteen hominids who are like us yet unlike us: infants, children, mature adults, and elderly creatures who had very small bodies and smaller brains. Yet they buried their dead, previously thought inconsistent with that cranial capacity. (Or maybe they didn’t and it was accidental.) A new species, Homo naledi.   Way more than a finger bone or a couple of teeth.

Because the site research team needed half-a-dozen very thin people with graduate degrees in paleoanthropology, that group was all women, apparently with considerable esprit de corps. Great story.

Because fossils were so scarce, professionals developed considerable skill in gradually extrapolating the rest of a skeleton from very few bones.  That they would overreach is hardly surprising.  Lee Berger’s comment on the abundance of material now is therefore fascinating.  He and other researchers no longer have to speculate.  They don’t have to come up with theories and try them out painstakingly one by one.  Answers pop up before theories can even be fully formed.