[The term above has apparently been used by a Professor Fox, but in the sense of a superior, genetically "pure" species of homo sapiens, which is not how I am using the term.]
The title is the name I give, ex hypothesi et arguendo, to humans living in what Keith Stanovich calls the Age of Darwin. This is our age. It is the age in which Darwin's breakthrough has finally begun manifesting its deepest implications and broadest applications in society at large. It is the age in which arguing against Darwin, other than in order to refine his basic theory, is to assume a huge burden of proof and to hear in reply, "Adversus solum ne loquitor."
All I will say, now, about this sea change, as Stanovich would have it, is this:
The universalization of genetics (i.e., "geneticism") has merely biologized the dogma of original sin.
As you walk through any shop or on any street, the people you see may appear (phenotypically) fine and dandy. But what we know of genetics is that, in fact, lurking deep within, on the helical tracks of their very being, there could be any number of genetic disorders waiting to manifest. Everyone is, knowingly or unknowingly, the victim of a great fall from genetic purity and it is only a matter of time until the effects become apparent. Further, this primal corruption, which subjects the individual to the uncaring, unceasing vagaries of selfish nature, is transmitted by propagation, not by imitation (as at Trent, "... hoc Adae peccatum, quod origine unum est et propagatione, non imitatione tranfusum omnibus...."). No matter how virtuous or "integrated" a person may seem, the fact is, in the aetas Darwinum, they are corrupt, like everyone else.
What this shift indicates, of course, is a total demoralization of what the doctrine of the Fall means. Fr. Keefe, in volume 1 of Covenantal Theology, makes this point very clear. If the Fall is not seen as a radically moral, and therefore radically free, occurrence ,it loses its intrinsic intelligibility. The biologization of our fallenness then is but one indication of the intrinsically anti-freedom and amoral dynamic of our age. Our biological fallenness seems as chilling and alienating as any skewed version of the Fall. For unless Adam is seen as our metaphysical, and not necessarily temporal, head, humanity is just as subject to a temporal (i.e., amoral) necessitarianism as a biological one. What Adam did in his own time, a moment integrally coterminous with the Event of Creation, is the metaphysical basis for our own fallenness. His fall is ours, and vice versa, synchronically, and we can see this fallen link in the course of historically discrete diachronic consequences.
[P.S. I make no claims for the quality of my Latin. I use it for my own edification and I misue it, I appreciate being told how to correct it. Also, as the Solemnity of our Lady's Assumption was this week, I hope I can soon post a few thought from Fr. Keefe on that event.]