selection pressure

(redirected from Evolutionary pressure)
Also found in: Encyclopedia, Wikipedia.

se·lec·tion pres·sure

impact of effective reproduction due to environmental impact on the phenotype.

selection pressure

Any change in the environment that encourages particular mutations to succeed. For example, antibiotic use kills susceptible bacteria and allows microorganisms with resistant genes to survive and proliferate.

selection pressure

a measure of the amount of relative reproductive disadvantage of one phenotype over another of the same species living together in the same area. Such pressure is usually represented by the selection coefficients which can have a value from zero (no selective disadvantage, maximum FITNESS) to 1.0 (complete selective disadvantage leading to actual death or GENETIC DEATH, minimum fitness).
References in periodicals archive ?
Human facial recognition has been demonstrated in birds (pigeons especially), sheep, dogs, cows and horses--all creatures which possess a neocortex and have been domesticated and have possibly experienced evolutionary pressure to recognise humans.
This suggests that the higher prevalence of the protective AS3MT haplotype within the SAC individuals does not merely reflect general genetic differences between populations, but rather provides evidence for evolutionary pressure that led to arsenic-protective adaptation in the AS3MT gene.
Imagine all the evolutionary pressure placed on influenza to develop ways of evading a healthy immune system--and then imagine how freely it could run amok if it encounters a weak immunity!
Northern Europeans have variants in the lactase gene, which is meant to be switched off after you've weaned, but the development of dairy farming in Northern Europe was an evolutionary pressure because there's a lot of milk around.
Further, Wray and Grace (2007) argue that early hominin language would have been extremely formulaic and elliptical within a single linguistic culture, but would have met cultural evolutionary pressure to analyze when encountering a group speaking a different language.
In addition to general diversity patterns of different fossil groups, we will study three distinctive intervals in detail, which should document biodiversity and the intensity of evolutionary pressure in (1) greenhouse (Givetian), (2) beginning climate change (Early-Middle Frasnian; e.g.
Natural evolutionary pressure drove the transformation from inexpensive PCs to more expensive PCs.
This constant pressure of exposing newer antibiotics to an already aggressive species of organism is putting evolutionary pressure, at an alarming rate, to either transform the physiology of the microorganism or better control its environment.
The essence of such systems is to remove ambiguity; the evolutionary pressure of natural human knowledge exchange is to embrace ambiguity.
The problem with that hypothesis is that famine probably does not exert a lot of evolutionary pressure, Dr.
'The crew's Europeans would still prefer to eat face-to-face.'" No word on whether Europeans subjected to the evolutionary pressure of being cooped up with crew mates 24/7 might eventually sour on the notion of breaking bread with them at the end of every day.
The likely increased use of oral antibacterial drugs for patients with possible influenza and for prophylaxis and treatment of secondary bacterial pneumonia would enhance the existing evolutionary pressure toward resistance.

Full browser ?