The OP: “Why don’t I have a bone in my penis?”
You mean you don’t?
Well MY husband has a bone in HIS penis. A big one, too.
At least, that’s what he tells me, and I haven’t seen anything to make me think it’s not true. 
Humans have the largest penises among the primates; larger than chimpanzees, orangutans and even gorillas.
…and nothing will impress people more than just casually mentioning you’re ten times as large as a gorilla…
If true, I think it’s obvious why they went away…the poor bastards couldn’t get any.