[furball4paws]

Ah, VR, I'm glad you are here.

i have a question that will make the creationists yelp for joy, but I think it needs some attention.

The area of human evolution is an area I know only rudimentary things about. There is much empahsis on braincase size on both sides.

1. I take it that it is not only the brain case size (volume) that is used to show lineage, but also what parts of the braincase are increasing?.

2. i ask this because of the common observation like this one: My neighbor on one side has a St. Bernard - really big and really stupid. My neighbor on the other side has a chihuahua, small yappy, but quite "smart". Considering the anatomy of a dog (all the same muscles, bones, etc. for both large and small dosg - is there increased nervous tissue in a large dog?), it seems that a chihuahua's brain would be capable of operating a St. Bernard. What's all that extra brain material doing in the St.Bernard? I think it's sawdust, my neighbor won't let me do an autopsy on that St. Bernard while he's still alive.

[VadeRetro]

I don't really know for sure. Part of it is the Saint's brain isn't as much bigger than the toy yap-yap thing's as its head size would indicate. Just for one thing, notice that toy dogs have an "infantile" look: huge eyes and smallish muzzles on rounded heads. There's a minimum dog brain (and eye) size and they're pushing it already. The Saint has big jaws and a thick skull.

Intelligence and brain size only correlate roughly. Dante's brain capacity was on the small size. (OTOH, I'm reading Divina Commedia in English and not finding it all that hot.) While Neanderthals had bigger overall brains than Cro-magnon Man, the regions enlarged were somewhat different. Whales and elephants have big brains, too. They're pretty smart in absolute terms but not particularly in proportion to brain size.