***Genes and inclusive fitness: genes are packets of DNA that are inherited by children from their
parents in distinct chunks. Genes are the smallest discrete units that are inherited by offspring intact,
without being broken up. According to modern evolutionary biologists, evolution operates by the
process of differential gene reproduction; define reproductive success relative to others. The genes of
organisms that reproduce more than others get passed down to future generations at a greater
frequency than do the genes of those that reproduce less. Survival is critical for reproductive success, so
characteristics that lead to greater survival get passed along. Success in mating is also critical for
reproductive success, and the qualities that lead to success in the same-sex competition or to success at
being chosen as a mate to get passed along.
The modern evolutionary theory based on differential gene reproduction is called inclusive fitness
theory. The “inclusive” part is the fact that the characteristics that facilitate reproduction need not
affect the personal production of offspring. They can affect the survival and reproduction of genetic
relatives as well.
***Products of the evolutionary process: All living humans are products of the evolutionary process, the
descendants of a long line of ancestors who succeeded in surviving, reproducing, and helping their
genetic relatives. The evolutionary process acts as a series of filters. In each generation, only a small
subset of genes passes through the filter. The recurrent filtering process lets only three things pass
through: adaptations; by-products of adaptations; and noise, or random variations.
*Adaptations: are the primary products of the selective process. An adaptation can be define as a
“reliably developing structure in the organism, which, because it meshes with the recurrent structure of
the world, causes the solution to an adaptive problem”. Adaptations might include a taste for sweet and
fatty foods, the drive to defend one’s close relatives, and preferences for specific mates, such as those
that are healthy. Let’s examine the components of the definition of adaptation. The focus on reliably
developing structure means that an adaptation. The focus on reliably developing structure means that
and adaptation tends to emerge with regularity during the course of a person’s life. The mechanisms
that allow humans to see, for example, develop reliably. But this does not mean that vision develops
invariantly. The development of the eye can be perturbed by genetic anomalies or by environmental
trauma. The emphasis on reliable development suggests that evolutionary approaches are not forms of
“genetic determinism”. Environments are always needed for the development of an adaption, and
environmental events can always interfere with or enhance such development.
The emphasis on meshing with recurrent structures of the world means that adaptations emerge from,
and are structured by, the selective environment. Features of the environment must be recurrent over
time for an adaption to evolve. The venomous snakes must be recurrently dangerous, ripe fruit must be
recurrently nutritive before adaptations to then can emerge.
Finally, an adaptation must facilitate the solution to an adaptive problem. An adaptive problem is
anything that impedes survival or reproduction. Stated more precisely, all adaptations must contribute
to fitness during the period of time in which they evolve by helping an organism survive, reproduce, or
facilitate the reproductive success of genetic relatives.