Quick Answer. The function of motor neurons is to release the neurotransmitter acetylcholine, which are released at a junction known as the neuromuscular junction, that bind to postsynaptic receptors, causing the muscle fiber to respond and result into a muscle movement.
The critical element that culturally sets humans apart from other species is the functional superiority of the human brain. That existing human culture has three axial components, namely politics, religion, and technology, which influence the affairs of mankind, must be obvious to all with a passing interest in human behaviour.
Humans have been somewhat more efficient at this mode of locomotion. Like australopithecines , early humans were light in frame and relatively short. They were only about 3 ft. 4 in. to 4 ft. 5 in. tall (100-235 cm) and weighed around 70 pounds (32 kg) The evolution of larger bodies occurred later in human evolution. The differences between australopithecines and early humans are most noticeable in the head.