The phrase "ancestral man" is correct and usable in written English.
It can be used in discussions related to anthropology, evolution, or historical studies to refer to early human ancestors or species.
Example: "The study of ancestral man provides insights into the evolution of modern humans and their behaviors."
Alternatives: "early human" or "primitive human".
In his extreme male brain theory of autism, Baron-Cohen postulates that having a typically male brain was adaptive for ancestral men and having a typically female brain was adaptive for ancestral women.
On Kiwai, the large island at the mouth of the Fly River, initiation was marked by the display of naturalistic, almost life-size figures of ancestral men and women.
The evolutionary theory, though not new, goes something like this: Ancestral men, unlike women, could never be certain of the paternity of their offspring, and thus jealously guarded the potential mothers of their children so as not to waste time and resources raising another man's offspring.
Second, a narrow waist is a visual cue of the absence of pregnancy and therefore current fecundity a feature that ancestral men sought in women.
From our perspective, a remarkable exception to this rule is the ancestral men gene cluster that was, for unknown reasons, 'frozen' in the plastid genome of a single algal group, the Cyanidiales.
As reproductive gains from short-term mating would be largely eliminated if a female was not fertile, it is possible that ancestral men may have had an adaptive need to identify and pursue short-term partners who were healthy and fertile (Symons, 1979).
Also, all men carry the same Y chromosome, a surprising situation derived from the fact that in the ancestral human population some men had no children or only daughters, so that in each generation some Y chromosomes disappeared until only one was left.
All Y chromosomes fall on branches of a single tree, descended from one man in the ancestral human population.
Related site Overview of ancestral human species.
