A type of selection that favors phenotypes at one extreme of a trait’s range is called directional selection. Directional selection occurs when one extreme phenotype is favored by natural selection. During stabilizing selection, the intermediate phenotype is favored and becomes more common in the population.
What pattern of natural selection changes the distribution of a trait in favor of the intermediate phenotype?
Diversifying (or disruptive) selection: Diversifying selection occurs when extreme values for a trait are favored over the intermediate values. This type of selection often drives speciation. Diversifying selection can also occur when environmental changes favor individuals on either end of the phenotypic spectrum.
How does natural selection change the distribution of a trait?
Natural selection on single-gene traits can lead to changes in allele frequencies and, thus, to changes in phenotype frequencies. Natural selection on polygenic traits can affect the distributions of phenotypes in three ways: directional selection, stabilizing selection, or disruptive selection.
What are three types of natural selection?
The 3 Types of Natural Selection
- Stabilizing Selection.
- Directional Selection.
- Disruptive Selection.
What is a good example of Intrasexual selection?
Intrasexual selection, on the other hand, occurs between members of the same sex. For example, male sea lions compete for dominance over rookeries of females. Here, intrasexual selection acts on the physiology of the sea lion, to make it large enough to compete with other males for a group of females.
What situations will lead to natural selection?
Only the successful competitors will reproduce, mortality is very high. Four (4) conditions for natural selection. Four conditions are needed for natural selection to occur: reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population.