Discover is running a piece on the “forgotten race” of hominids the Boskops, the remains of which were discovered in South Africa in 1913:
The scientific community of South Africa was small, and before long the skull came to the attention of S. H. Haughton, one of the country’s few formally trained paleontologists. He reported his findings at a 1915 meeting of the Royal Society of South Africa. “The cranial capacity must have been very large,” he said, and “calculation by the method of Broca gives a minimum figure of 1,832 cc [cubic centimeters].” The Boskop skull, it would seem, housed a brain perhaps 25 percent or more larger than our own. […]
Boskop’s greater brains and extended internal representations may have made it easier for them to accurately predict and interpret the world, to match their internal representations with real external events.
Perhaps, though, it also made the Boskops excessively internal and self-reflective. With their perhaps astonishing insights, they may have become a species of dreamers with an internal mental life literally beyond anything we can imagine.
The authors of the piece, Gary Lynch and Richard Granger (who co-authored the book Big Brain: The Origins and Future of Human Intelligence), wonder why the Boskop discovery has been almost entirely forgotten. University of Wisconsin paleoanthropologist has an answer for them:
This is obscure knowledge, but for a good reason — it’s obsolete and has been for fifty years! […]
What happened is that a small set of large crania were taken from a much larger sample of varied crania, and given the name, “Boskopoid.” This selection was initially done almost without any regard for archaeological or cultural associations — any old, large skull was a “Boskop”. Later, when a more systematic inventory of archaeological associations was entered into evidence, it became clear that the “Boskop race” was entirely a figment of anthropologists’ imaginations. Instead, the MSA-to-LSA population of South Africa had a varied array of features, within the last 20,000 years trending toward those present in historic southern African peoples.
However:
To be sure, there has been a reduction in the average brain size in South Africa during the last 10,000 years, and there have been parallel reductions in Europe and China — pretty much everywhere we have decent samples of skeletons, it looks like brains have been shrinking. This is something I’ve done quite a bit of research on, and will continue to do so, because it’s interesting. But it is hardly a sign that ancient humans had mysterious mental powers — it is probably a matter of energetic efficiency (brains are expensive), developmental time (brains take a long time to mature) and diet (brains require high protein and fat consumption, less and less available to Holocene populations).