It'd be more hygienic
if they had a plague-infested GIBBON...
The Big Bang Theory Season 2, Episode 4
But the GIBBON doesn't know
what it's categorized as.
The Big Bang Theory Season 8, Episode 8
...and his sister just successfully grew
a human pancreas in an adolescent GIBBON.
The Big Bang Theory Season 2, Episode 15
The GIBBON is the only member
of the ape family not classified as a great ape.
The Big Bang Theory Season 8, Episode 8
Why else would you grow
a pancreas in a teenaged GIBBON?
The Big Bang Theory Season 2, Episode 15