Nicholas Humphrey and John Skoyles from the London School of Economics and Roger Keynes from Cambridge University have suggested that their gait is due to two rare phenomena coming together.
•
Kenichi Ito is a Japanese man who is famous for speed running on four limbs.
Since Patrick's alien form was quadrupedal (as opposed to bipedal, like Eve's form), bigger, and more 'brutish' in appearance than hers, it is assumed that this must be the common appearance of most of, if not all of, the males of the alien species.