Wandering an arid region of the ancient supercontinent of Pangea about 260-million years ago, the pre-reptile Bunostegos akokanensis is the oldest known creature to have walked upright on all fours, according to a newly published study.
Wandering an arid region of the ancient supercontinent of Pangea about 260-million years ago, the pre-reptile Bunostegos akokanensis is the oldest known creature to have walked upright on all fours, according to a newly published study.