Sphaeran humans are -biologically speaking- virtually identical to the humans of the planet Earth, and many Sphaeran human cultures remarkably parallel certain Earthly cultures; in this respect, they are virtually the "poster children" of convergent evolution.
Civilization and Culture
The modern human species, Homo sapiens, occurs naturally on two planets: Earth, in the Sol system, and Sphaera, in the Aurin system. In this respect they are unique among the sapient beings of the galaxy. Their ancestors, H. erectus, were discovered on Earth by the planet's former sapient inhabitants, the harpies and karura. The discovery of a fledgling sophont species on an easily accessible planet prompted the academic leaders of interstellar Venusian civilization to enact Project CINDER -using the primitive hominids as their control species. After the Collapse, hominid evolution on Sphaera progressed very similarly to its Earthly counterpart. This resulted in a long period of general societal confusion and vague existential dread immediately after Terran and Sphaeran humans encountered each other for the first time.