De Vany has worked on the concept of evolutionary fitness (similar to the Paleolithic lifestyle).

Promiscuity increases the likelihood of having children, and thus evolutionary fitness.

But that doesn't mean their "evolutionary fitness" is increasing.

First, inbreeding forces competition with relatives, which decreases the evolutionary fitness of the species.

First, if the period for learning is short, language does not develop as well, and thus decreases the evolutionary fitness of the individual.

This can, among other things, result in the formation of complex social processes conducive to evolutionary fitness.

The central concept of natural selection is the evolutionary fitness of an organism.

Within the individual haystacks the selfish organisms benefit in terms of evolutionary fitness.

This greatly increases plants' ability to cross-pollinate, which maintains and possibly even improves their evolutionary fitness.

Socio-biology views human psychological traits to be ultimately understandable in terms of evolutionary fitness.