another recent species in genus Homo?

[eub]

http://www.newscientist.com/news/news.jsp?id=ns99996588

The remains of a tiny and hitherto unknown species of human that lived as recently as 13,000 years ago have been discovered on an Indonesian island.
[...]
The female skeleton, known as LB1 - or by the nickname "Ebu" - has been assigned to a new species within the genus Homo - Homo floresiensis. Examination of the remains shows members of the species stood just 1 metre tall and had a brain no bigger than a grapefruit.

Comments

[jinian.livejournal.com]

That's really cool. I don't quite understand why they're so surprised that human intelligence can reside in small skulls, though. Haven't there been very small people working as circus freaks every so often, and aren't they functional humans?

[eub.livejournal.com]

Yeah, I don't know. I wonder how small a small skull runs.

talk.origins says that the brain volume of a so-called normal modern human is about 1000 to 1600 cc, ranging down to 900. If this "grapefruit" is a five-inch sphere, that's (* (/ 4 3.0) 3.1416 (pow (/ (* 5 2.54) 2) 3) ) 1070 cc.

[jinian.livejournal.com]

This article says 380 ccs for H. floresiensis brains.

Strangely difficult to find information on very small H. sapiens brains. Here is a very odd page on which one can skip down to "15 VERY SMALL PEOPLE" or scroll through the little icons of the first ten men in space and other things. Clearly some of the very small people were intelligent, but it doesn't say anything about the size and quality of their organs.

[eub.livejournal.com]

Wow, my grapefruit was way out of whack.

That is an odd page indeed. Yeah, I can't find any information specifically on small people's organ volumes either. One wonders how H. floresieses were proportioned, head to body, compared with various small sapientes.

small brains

[hattifattener]

There's an obscure form of hydrocephaly in which the ventricles are hugely enlarged but the intracranial pressure is normal. It's not, apparently, fatal, and people with the problem lead normal lives --- unlike other kinds of hydrocephaly. But since the ventricles are enlarged, they have much less actual brain matter than most people. Still, they're usually of normal intelligence. So it seems that it's possible to have H.sap.-level intelligence with much less brain matter than we normally have.

Re: small brains

[eub.livejournal.com]

Oh, I'd forgotten about that. Haven't managed to google up any quoted brain volumes.

Seems there ought to be some reason for all of this expensive brain tissue. I wonder if people with that condition show less redundancy.