Every mammal in the world (except humans) have a “penis bone” or bacula to acquire an erection for mating. The longest being the blue whale at 6 ft.
It is perfectly normal to shed up to 200 strands of hair daily from your head.
Bugs don’t have lungs, they breathe by absorbing oxygen through their “skin”. They can’t grow as big as humans because their tissues would be too thick to get oxygen to vital organs.