Are we really all so different?
What if we slept all day like cats?
Would this benefit us as a species? Probably not. Our muscles would atrophy and we'd end up like those people you hear about on the news who fuse to their mattresses and have to be airlifted to the ER. Then again, sleeping is pretty great, so maybe it's a fair trade off?
What if we shot blood from our eyes as a self defense mechanism like horned lizards?
Would this benefit us as a species? Absolutely. Plus it would make for a totally badass party trick, and bring a whole new facet to death metal concerts.
What if our faces ballooned to an enormous size like a pufferfish every time were were annoyed?
Would this benefit us as a species? Debatable. It would probably hurt. It might lead to a more honest society, however.
What if we gave birth to giant litters of babies like dogs?
Would this benefit us as a species? Nope. The world would quickly become overrun and you can't drop your brats off at the pound when you get sick of them.