Sunday, December 16, 2007

Amber & Gorilla Heads

ALH is running around like crazy, so it's me, Amy, guest-blogging for her again. She worked at the ape house from 7 to 3:30 and now has to wash off the lemur poop in her hair, bundle up, and race back to Zoo Lights from 5 to 8:30. It's a very zoo-y day.

She shouted to me as she rushed into the shower that she learned today about why the older gorillas have such high head-backs. It's called a sagittal crest, and it's where the gorilla's powerful jaw muscles anchor. Older gorillas have more powerful jaws, and there's a part of the skull that sort of expands as they get older to allow for the muscle growth.

Silverbacks, the dominant male gorillas, have the most prominent sagittal crests. It's a secondary sex characteristic meant to impress the lady gorillas. Orang utans and my family, the Bili apes have them too.

Mrrow. Look at the head-back on this babe.

1 comment:

Anonymous said...

I never knew this about why the apes had funny bumps on top of their heads. Chimpy!