Final answer:
The scientific name for "upright man" is Homo erectus, a significant hominid species that lived approximately two million years ago and is known for being the first to walk entirely in an upright position.
Step-by-step explanation:
The scientific name for "upright man" is Homo erectus. This species, which emerged in East Africa around two million years ago, is believed to have evolved from Homo habilis. Homo erectus was the first hominid to live entirely on the ground and to walk or even run exclusively in an upright position.
Being upright had significant implications for the species, such as requiring a change in diet towards foods that were easier to digest, like nuts, fruits, tubers, honey, and meat. Although living on the ground presented increased danger from predators, the upright position allowed Homo erectus to use their hands for making and using tools, which became more sophisticated over time.
Known for their long legs and diminishing jaw protrusion in comparison to earlier hominids, Homo erectus had a cranial capacity averaging 900 cubic centimeters and exhibited physical features that were more similar to modern humans than previous species did. It represents a critical evolutionary stage in the development of the genus Homo, leading to the emergence of Homo sapiens later in prehistory.