Biography
Named for the art of Frank Frazetta, Frazetta Man is the generic subhuman native of the Lost World, or else the relic of a bygone age frozen in the ice. He most likely wants our women, and is prepared to pursue them across hundreds of miles of jungle and savanna. He is applied in hordes, can rarely be reasoned with, and basically exists to be triumphed over by Mighty Whitey so the Hollywood Natives may be properly awed.
Your basic Frazetta Man has the wiry build of a chimpanzee, though he is generally around human size if not larger. He'll be covered in hair (usually not fur) and will rarely wield any weapon more sophisticated than a knobkerrie. Seldom if ever will females or children of the species be seen, perhaps explaining his fixation on the Nubile Savage in her Fur Bikini.note His language, if he has progressed beyond the grunting stage, will be simple and brutal, and his gods will exist primarily to excuse his bloodthirsty nature.
Although we tend to associate this trope with the Two-Fisted Tales and Jungle Opera of the early 20th Century, this trope is actually Older Than Dirt. There are a few very old instances in the Folklore section below, and an Ur-Example borderline Frazetta Man even acts as the Deuteragonist in one of the oldest surviving stories in the world.
In Real Life, there were indeed many species of "ape-men", those being various non-Homo hominids, many of which have been classified as australopithecines, with the best-known being the Australopithecus genus itself (often viewed as the ancestor of Homo). However, while these creatures were indeed "transitional forms", sharing characteristics of both modern humans and more typical apes such as chimpanzees, one of their more human-like traits was their gracile build, meaning they lacked the physical strength of a chimp, not helped by the fact that most australopithecines were seldom over 4 feet tall. Many of them also lived before the emergence of Homo (during the latest Miocene-Pliocene), though some did overlap with early humans such as Homo habilis and Homo erectus during the Early Pleistocene, most notably the robust australopithecines (Paranthropus), though they were still on the short side and largely herbivorous (much like gorillas), so when the two crossed paths, it's likely that the more human-like hominids would have been the aggressors. Homo erectus itself was another inspiration, as it was originally described from very incomplete remains as "Pithecanthropus erectus" (meaning "upright ape-man"), and some workers interpreted it as a "missing link" between humans and apes, leading to early reconstructions showing it as a 6-foot ape-man, but once we discovered more material of this species, it became clear that it was far more human-like than initially thought, leading to it being placed in Homo.
One possible modern take on this trope is Bigfoot, Sasquatch, and Yeti, which are speculated by some people to really be surviving prehistoric hominids, though of course their existence hasn't been proven. Though interestingly, these ape-like creatures aren't something new and have existed in the mythology of certain peoples for thousands of years, leading some to suspect that the oldest examples may be distorted accounts of now-extinct species of humanoid encountered by Early Man. Relatedly, ancestral memories of Frazetta Man may also be pitched as the slightly-more plausible inspiration behind legends of The Fair Folk, trolls, and the like. In anthropology, this is referred to as the theory of "fairy euhemerism", and is generally not taken very seriously.
More intelligent species of Frazetta Man exist, physically little different but typically adorned in primitive jewelry and using weapons as advanced as swords or axes. Such varieties often function as Mooks for the local Big Bad, and may shade over into orcish or Beast Man territory. Compare Killer Gorilla, where non-human apes get a similarly brutal, savage portrayal. See The Morlocks for Frazetta Man's subterranean cousins; where Frazetta Man merely retained ancestral primate traits, the Morlocks developed their atavistic features as an adaptation to living underground (or, in futuristic settings, to living and working in dingy industrial environments). Also see Pelts of the Barbarian, for when primitive humans wear clothes made of fur instead of simply being covered in hair themselves.
Contrast Handsome Heroic Caveman.