Bipedalism A form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs.
Makes sense. Humans, as one of the afore mentioned organisms, have unrivalled travelling efficiency.
Didn't know that! Our lower appendages are awesome when you think about all the fantastic things we can do with them. On ya marks, get set, GO!
I prayed for freedom for 20 years but received no answer until I prayed with my legs. Frederick Douglass E N J O Y