selection pressure


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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 ?
419); behavioral patterns which have arisen from a selection pressure throughout our evolution.
The changing mix of enrollees and adverse selection pressure has likely been a significant cause of the large average premium increases," the ASPE said.
From round four (R4) through round seven (R7), the protocol for R3 was repeated with the exception of decreasing the RNA-cell incubation time, from 1 hour to 30 minutes with the intent of further increasing the stringency of the selection pressure.
The retention of cold-acclimation capacity in Kansas and Texas populations indicates that low temperature stress remains a potentially important selection pressure in these regions and this conclusion is consistent with climatic data indicating that these more southern locations still can experience freezing temperatures.
The former Harlequins stand-off makes the temporary switch from Newcastle Falcons to ease the selection pressure on the Pro12 champions.
Phylogenetic inference: The MEGA6 software (Tamura et al., 2013) was used for determining the best evolutionary model, for phylogenetic tree construction, estimation of evolutionary divergence, determining the amino acid composition and estimation of selection pressure on coding sequences.
The broad sense heritability was 99.9% and the narrow sense heritability was 57.3% indicating that number of bolls/plant is highly heritable and further significant amount of improvement up to the tune of 57% could be realized if progenies are selected under defined high selection pressure following pedigree progeny selection procedure.
With his Falcons side unbeaten in their three European Rugby Challenge Cup games to date and homing in on a quarter-final place, the 24-year-old believes there are wider benefits with a host of fringe players applying serious selection pressure ahead of the return to Premiership rugby.
Reliance on one method of weed control imposes selection pressure, which can lead to population shifts to tolerant species or selection of resistant biotypes.
That suggests that genes encoding those proteins come under intense selection pressure by the immune system during initial acute infection.