Bipedalism Bipedalism Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning "two feet" (from the Latin "bis" for "double" and "pes" for "foot"). Types of bipedal movement include walking, running, or hopping. Few modern species are habitual bipeds whose normal method of locomotion is two-legged. Within mammals, habitual bipedalism has evolved multiple times, with the macropods, kangaroo rats and mice, springhare, hopping mice, pangolins and hominin apes (australopithecines and humans) as well
How many angels can dance on the head of a pin? about how many could perch at the same time on the head of a pin"". Dorothy L. Sayers argued that the question was "simply a debating exercise" and that the answer "usually adjudged correct" was stated as, "Angels are pure intelligences, not material, but limited, so that they have location in space, but not extension." Sayers compares the question to that of how many people's thoughts can be concentrated upon a particular pin at the same time. She concludes that infinitely many angels can be located on the head of a pin, since they do not occupy any space there: