Or we may wish to maintain traits that reduce the fitness of individuals because these same traits are useful to us, as in the case of domesticated species (e.g., greater allocation to grain or seed set; Denison et al. 2003) or harvested wild species (e.g., big horns in game animals and large size in fish; Heino 1998; Harris et al. 2002).
While Pernès [ 79] predicted that the linkage of domestication genes can aid cross-pollinated crops in maintaining trait complexes that comprise the domestication syndrome, and further modeling has supported this prediction [ 80], empirical studies (including the present study) have indicated that these QTL clusters are also found in highly selfing crops [ 6, 81- 83].
Evolutionary theory has been successfully developed as a tool for investigating the ultimate causation of biological variation in multicellular organisms, and is increasingly being applied to explain why genetic variation is maintained for traits, such as virulence, in unicellular parasites.
Noticeably, Fdh was independently lost in H. mustelae, a species that has instead maintained the trait and an Sec-encoding SelD as the sole selenoprotein (see fig. 3).
Pleiotropy can also help maintain costly traits, such as cooperation, when the costly trait is functionally connected to another trait under strong positive selection [ 50, 51].
Gene culture coevolution, when utilized appropriately, takes note of the social processes that necessarily maintain cultural traits, allowing it to pay due respect to these aspects in addition to the psychological underpinnings of culture.
We conclude that GE algae can be successfully cultivated outdoors while maintaining GE traits, and that for the specific GE algal strain tested here they did not outcompete or adversely impact native algae populations when grown in water taken from local lakes.
Furthermore, the action of the immune system and antimicrobial treatments impose further population bottlenecks that may help to maintain social traits in microbial pathogens.
Well-established theories of sexual selection maintain that traits which are favorable in mate choice will be strongly selected for, even if natural selection does not favor these traits.
Maintaining deleterious traits within a population indefinitely is likely to require scheduled releases of new RNA-guided gene drives to periodically overwrite the broken versions in the environment.
