Search results
Results from the WOW.Com Content Network
One example of a study was found in the 'yellow' D.melanogaster, the mating of these males was only beneficial when it was dark outside, or when they were in a dark environment. The mutation is not yet known why it occurs this way, but studies have mentioned that the females of this fly species may be turned off by the certain colour of the ...
Genetic pollution is a term for uncontrolled [1] [2] gene flow into wild populations. It is defined as "the dispersal of contaminated altered genes from genetically engineered organisms to natural organisms, esp. by cross-pollination", [3] but has come to be used in some broader ways.
Adaptive mutation, also called directed mutation or directed mutagenesis is a controversial evolutionary theory. It posits that mutations , or genetic changes, are much less random and more purposeful than traditional evolution , implying that organisms can respond to environmental stresses by directing mutations to certain genes or areas of ...
In contrast, the same conditions that can cause extinction in a sexually reproducing population can aid in the avoidance of mutation meltdown. In a tested environment, where variables can be theoretically manipulated, the strong mutation-selection in a large sexually reproducing population can be prevented from mutational meltdown if the birth ...
Population bottleneck followed by recovery or extinction. A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events such as famines, earthquakes, floods, fires, disease, and droughts; or human activities such as genocide, speciocide, widespread violence or intentional culling.
In nature, the mutations that arise may be beneficial or deleterious—this is the driving force of evolution. An organism may acquire new traits through genetic mutation, but mutation may also result in impaired function of the genes and, in severe cases, causes the death of the organism.
There are several methods, or forms, of mutation that exist including spontaneous mutation, errors during replication and repair, as well as mutation due to environmental effects. [8] These origins of mutations can cause many different types of mutations which influence gene expression on both large and small scales.
Conditional mutation is a mutation that has wild-type (or less severe) phenotype under certain "permissive" environmental conditions and a mutant phenotype under certain "restrictive" conditions. For example, a temperature-sensitive mutation can cause cell death at high temperature (restrictive condition), but might have no deleterious ...