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 ?
It has been shown previously that a 5[degrees]C difference in water temperature can cause a selection pressure strong enough to result in genetic differentiation (Dahlhoff & Somero 1993, Lin & Somero 1995).
However, if the process seems immutable, does this imply that selection pressure remains stable over time?
Unlike anthelmintic treatment, the resistant host does allow some worms to survive, so the selection pressure on the worms is much lower,' Eady says.
For there to be significant inherent mental differences among racial groups, there would have to have been significantly different selection pressure.
This preference Schiefenhovel takes as a proximate cause, behind which population control under selection pressure stands as a final cause.
If such patterns conferred some survival advantage early in life they would have come under stronger selection pressure than any detrimental effects they produced late in reproductive life |11~.
Similarly, Lotus Corporation, despite the turbulence of the computer software industry, is buffered from selection pressure due to the phenomenal success of its initial product introduction.
Chapter 25 Environmental Microbial Communities Living Under Very High Antibiotic Selection Pressure
This analysis provides new evidence that regulators of innate immunity may exert selection pressure on tumors and play an active role in the natural history of colorectal cancer.
None of those thrown in took the opportunity presented them to place any kind of selection pressure on their manager.
None of the players thrown in took the opportunity presented to them to place any kind of selection pressure on their manager.