The genetic mutation which causes sickle-cell anemia is non-neutral because it affects survival and fitness.

Some genomic differences may not affect fitness.

But can the number of offspring affect fitness over the long term, into adulthood?

Epigenetic inheritance may only affect fitness if it predictably alters a trait under selection.

Duplicated genes have also been observed to affect fitness immediately after duplication (see Discussion), providing a short-term advantage for duplication.

They will be encouraged to consider the many factors which affect personal health and fitness.

S. musiva affects fitness in two ways, depending on how it manifests itself, either as a leaf spot or a canker.

Having a mating preference is advantageous in this situation because it directly affects reproductive fitness.

Choosing genetically compatible mates could result in optimally fit offspring and notably affect reproductive fitness.

Most teams are playing three games in eight days in the first round, and further compression of that schedule would begin to affect depth and fitness.