Friday, September 11, 2015

The Spiritual Evolution of Homo naledi

Whatever it means to belong to the genus Homo, it doesn’t seem to have much to do with brain size.  If Homo is more than an artificial category (like Socrates’ “all the numbers except 17”), if the homonini are a large trunk branching off from the chimpanzees, one branch of which led to Homo sapiens, the question arises whether all the homonini are indeed members of the human clade in some essential sense.  Are (or were) Homo erectus and Homo neanderthalensis human? 
This question occurred to me today as I listened to news of the discovery of a new hominid species, Homo naledi.  A treasure trove of naledi bones were discovered deep in a cave 30 miles from Johannesburg, South Africa.  Listening to one of the explorers describing how they reached the bones affected me so strongly I had to pull off the road.  I have explored a number of wild caves and suffered once from an almost disastrous case of claustrophobia.  She had to insert herself, pretzel-style, through a crack that was only seven inches wide.  She’s a better man than I am Gunga Din.  
Here is the creature they brought back:
Their feet were incredibly similar to those of modern humans, says Harcourt-Smith, who led the study of the newly discovered creature's feet. Homo naledi stood about 5 feet tall, and yet they had a skull whose volume was only about one-third of ours, a tiny brain in comparison with that of the modern human. Despite their ability to walk upright, with stiff feet and toes that couldn't grasp things as easily as more primitive animals, they had shoulders and hands indicating they would have been quite comfortable climbing through trees and, perhaps, through caves.
This is astonishing.  It has been generally assumed that as our ancestors evolved they maintained a more or less even aspect ratio‑feet getting bigger along with the ass and the elbows and the earlobes.  These critters seem to have been evolving from the ground up.  They had to buy size 9 shoes and hats that would fit a cabbage patch doll. 
And yet…  They were admirably fit for climbing up into trees or down into caves, but why the latter?  It must have easier for them to negotiate the narrow passage than it was for our modern day cavers but they had to do it in the dark.  So what the hell were they doing down there? 
Geological features show that the bodies arrived in the cave over a period of time, meaning this wasn't a one-off event or catastrophe of some sort. Teeth show that the remains come from individuals of many different ages, from young children to teenagers to elderly adults. There aren't signs of violence, falls, or cannibalism. And there are almost no remains from any other creature, indicating that this was a place that had to be sought out deliberately — not a place that some kind of creature dragged its prey.
The only explanation that stands at present is that this was a burial chamber.  They were going to a great deal of trouble to hide their dead. 

To crawl that deep into the dark in order to inter the remains of their loved ones suggests a consciousness of mortality that is fully human, despite their small brains.  Whatever changed when we and our nearer relatives branched off from the chimpanzees, it was more than just bigger or smarter brains.  It involved a much more sophisticated self-awareness.  We evolved not just into more sophisticated physically and mentally subtle forms.  We evolved in the direction of more sophisticated ideas.  That is spiritual evolution and it may yet be the next frontier in evolutionary theory.  


  1. "So what the hell were they doing down there?" Perhaps they were searching for ancient ancestors, but, because it was dark, failed to find an exit. More seriously, couldn't they have been hunting for food and unable to find any? Might they not have starved to death?

    And if they did use the cave as a burial chamber, can we be sure that this was a spiritual event or that those they buried were loved ones? Might they not have buried their dead in the cave to be rid of the smell of the corpses? Or might they not have hidden their dead to avoid attracting pests or predators?

  2. Miranda: Its fairly easy in a cave to tell when one thing was deposited before another. Layers of sediment will usually tell that story. The Naledi bones were deposited over time, not all at once; so it wasn't a single disaster.

    There are much easier ways of disposing the dead than crawling a great distance into a dangerous cave. If not burial, then simply discarding them at a distance. These are the things that many creatures do. Going to more trouble than that to protect the ancestors from animals and pests is the kind of thing we do when we start to think that the ancestors still matter somehow. A concern for the dignity of the dead strikes me as a definitive sign of spiritual awareness.

  3. Dr. Blanchard: Thank you for your answer. What you say makes sense to me and if the purpose truly was burial I certainly agree with you.