It also did not comprehensively assess adaptive divergence between the groups, including their ability to rapidly adapt to changing conditions.
If it changes more rapidly, few adaptive walks will be completed, and the population will be poorly adapted most of the time.
That means, in the absence of a human kind of critical judgment, that useless or harmful cultural behaviors are likely to accumulate more rapidly than adaptive ones.
It is worth noting that under new selective pressures, such as oseltamivir antiviral treatment, recombinant viruses with enhanced viral polymerase activity have been found capable of rapidly generating adaptive mutations that may enhance viral fitness [40].
Such a high number of gene duplicates would suggest that the venom is evolving rapidly under adaptive, positive selection.
This phenomenon occurs, for example, when taxa speciate rapidly during adaptive radiation, and has been repeatedly reported from the cichlid species flocks in the East African Great Lakes [ 15, 17- 20].
These results stand in stark contrast to previous research on guppies showing extensive, repeatable, and rapidly evolving adaptive divergence between other types of environments (e.g., high predation versus low predation; high productivity versus low productivity) (Reznick and Bryga 1996; Reznick et al. 1997; Grether et al. 2001; O' Steen et al. 2002; Arendt and Reznick 2005; Gordon et al. 2009).
It seems apparent from species invasions that adaptive change can occur rapidly and that severe population bottlenecks do not preclude rapid adaptation (Sax et al., 2007).
Two processes can facilitate persistence of populations challenged with a rapidly changing environment: adaptive phenotypic plasticity and genetic adaptation.
