Cranial Evolution?

Question

"Scientists have found skeletons of a hobbit-like species of human that grew no larger than a three-year-old modern child (See pictures). The tiny humans, who had skulls about the size of grapefruits, lived with pygmy elephants and Komodo dragons on a remote island in Indonesia 18,000 years ago. "

(http://news.nationalgeographic.com/news/2004/10/1027_041027_homo_floresiensis.html)

I've seen several other articles related to this one. They indicate that even though these hobbit-humans had a brain size 1/3 that of the modern homo sapiens sapiens, the hobbit-humans were just as skilled at toolmaking as their early homo sapien neighbours.

What do you think this means for the theory that humans cognitively evolved through larger brain size?

Answer 1

No matter what brain size for proto-humans, or modern humans...it's how that brain and its functions are used that dictates intelligence...it's also how that intelligence is used that dictates whether or not it's 'intelligence'.

Good Morning!

Answer 2

You need to refresh the link. Fact of the matter is that while absolute size is less important than brain to body ratio and shape of the brain. As for tools, it is likely that they used tools developed by H. sapiens. Even neanderthals borrowed from the modern species of humans, and we have a large record of making fossils.

There is actually a lot of debate about the creators of tools, since it cannot be assumed that tools found at a site always will belong to a species found near that site.

Answer 3

Because the neandertal had a larger brain than did sapien, one might assume they were more intelligent, but their tool making remained static until about the time they encountered sapien.  Therefore, the sapien brain, though smaller, may have evolved to be more effecient.

Much dispute exists over the hobbit fossiles... some claiming they are modern sapiens suffering from a genetic disorder.  When MCPH1 (a gene that suddenly appeared ~37,000 yrs ago) has a defect, the brain growth is about 1/2 that of a normal human.  Others of course see them as Homo erectus that were subjected to dwarfism due to being confined on an island with limited food supplies.  So the debate over the Flores finds is still hot & heavy, with both sides having some valid points of evidence. The "Hobbit" has a smaller brain than did ancient Homo erectus.  More modern erectus finds had a brain size of about  3/4 the size of sapien.

I suspect the brain evolved to be both larger & more effecient cognitively as other abilities, such as smell & hearing ability were lost.