The Big Bang Theory Season 1, Episode 11

...Homo habilis would've figured out to kill the guy with the runny nose.

The Big Bang Theory Season 1, Episode 6

...I thought that Homo habilis line really put him in his place.

The Big Bang Theory Season 2, Episode 5

...how does the biologically superior Homo novus get to work...

The Big Bang Theory Season 2, Episode 5

Homo novus doesn't know.

The Big Bang Theory Season 9, Episode 24

is that Neanderthals and Homo Sapiens frequently mated with each other.