Assortative mating
Encyclopedia
Assortative mating and the related concept Disassortative mating, is the phenomenon where a sexually reproducing
organism
chooses to mate
with individuals that are similar (positive assortative mating) or dissimilar (negative assortative mating or disassortative mating) to itself in some specific manner. In evolution
, these two types of assortative mating have the effect, respectively, of increasing or reducing the range of variation (trait variance), when the assorting is cued on heritable traits. Positive assortative mating, therefore, results in disruptive natural selection, and negative assortative mating results in stabilized natural selection. Assortative mating occurs along many dimensions, including religious beliefs, physical traits, age, socioeconomic status, intelligence, and political ideology, among others( Kail, Robert V., and John C. Cavanaugh. Human Development: a Life-span View. 5th ed. Australia: Wadsworth Cengage Learning, 2010. Print).
It is mirrored by selective fertilization in plants.
. For some populations there are two different resources for which different phenotypes are optimum. Intermediates between these two phenotypes are less favorable. It is then favourable if the organisms can recognize mates that are optimized for the same resources as they are themselves. If mutations that make such recognition possible appear, these will be selected for.
can lead to a strategy of negative assortative mating.
Assortative mating among computer scientist
s with Asperger syndrome
could be contributing to the rise in juvenile autism spectrum disorders in Silicon Valley
.
Homogamy
is marriage
based on assortative mating.
-dwelling goby fish. The species live in a small area of rare coral
in the ocean around Bootless Bay in southern Papua New Guinea
which the parent species shun. The daughter species has become reproductively isolated
from the parent species even though the parent species surrounds the daughter species so there is no geographic isolation
. The speciation in the early stages would depend on assortative mating in which the evolving goby fishes would prefer to mate with other fish that preferred to spawn in the same area of rare coral.
Sexual reproduction
Sexual reproduction is the creation of a new organism by combining the genetic material of two organisms. There are two main processes during sexual reproduction; they are: meiosis, involving the halving of the number of chromosomes; and fertilization, involving the fusion of two gametes and the...
organism
Organism
In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...
chooses to mate
Mating
In biology, mating is the pairing of opposite-sex or hermaphroditic organisms for copulation. In social animals, it also includes the raising of their offspring. Copulation is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization...
with individuals that are similar (positive assortative mating) or dissimilar (negative assortative mating or disassortative mating) to itself in some specific manner. In evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
, these two types of assortative mating have the effect, respectively, of increasing or reducing the range of variation (trait variance), when the assorting is cued on heritable traits. Positive assortative mating, therefore, results in disruptive natural selection, and negative assortative mating results in stabilized natural selection. Assortative mating occurs along many dimensions, including religious beliefs, physical traits, age, socioeconomic status, intelligence, and political ideology, among others( Kail, Robert V., and John C. Cavanaugh. Human Development: a Life-span View. 5th ed. Australia: Wadsworth Cengage Learning, 2010. Print).
It is mirrored by selective fertilization in plants.
General characteristics
Assortative mating has been invoked to explain sympatric speciationSympatric speciation
Sympatric speciation is the process through which new species evolve from a single ancestral species while inhabiting the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organisms whose ranges overlap or are even identical, so that...
. For some populations there are two different resources for which different phenotypes are optimum. Intermediates between these two phenotypes are less favorable. It is then favourable if the organisms can recognize mates that are optimized for the same resources as they are themselves. If mutations that make such recognition possible appear, these will be selected for.
Humans
In humans, genetic counselingGenetic counseling
Genetic counseling or traveling is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning...
can lead to a strategy of negative assortative mating.
Assortative mating among computer scientist
Computer scientist
A computer scientist is a scientist who has acquired knowledge of computer science, the study of the theoretical foundations of information and computation and their application in computer systems....
s with Asperger syndrome
Asperger syndrome
Asperger's syndrome that is characterized by significant difficulties in social interaction, alongside restricted and repetitive patterns of behavior and interests. It differs from other autism spectrum disorders by its relative preservation of linguistic and cognitive development...
could be contributing to the rise in juvenile autism spectrum disorders in Silicon Valley
Silicon Valley
Silicon Valley is a term which refers to the southern part of the San Francisco Bay Area in Northern California in the United States. The region is home to many of the world's largest technology corporations...
.
Homogamy
Homogamy
-In sociology:Homogamy is marriage between individuals who are, in some culturally important way, similar to each other. Homogamy may be based on socio-economic status, class, gender, ethnicity, or religion...
is marriage
Marriage
Marriage is a social union or legal contract between people that creates kinship. It is an institution in which interpersonal relationships, usually intimate and sexual, are acknowledged in a variety of ways, depending on the culture or subculture in which it is found...
based on assortative mating.
Goby fish
Positive assortative mating is believed to be the cause of the speciation of a daughter species from the parent species of coralCoral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
-dwelling goby fish. The species live in a small area of rare coral
Coral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
in the ocean around Bootless Bay in southern Papua New Guinea
Papua New Guinea
Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...
which the parent species shun. The daughter species has become reproductively isolated
Reproductive isolation
The mechanisms of reproductive isolation or hybridization barriers are a collection of mechanisms, behaviors and physiological processes that prevent the members of two different species that cross or mate from producing offspring, or which ensure that any offspring that may be produced is not...
from the parent species even though the parent species surrounds the daughter species so there is no geographic isolation
Allopatric speciation
Allopatric speciation or geographic speciation is speciation that occurs when biological populations of the same species become isolated due to geographical changes such as mountain building or social changes such as emigration...
. The speciation in the early stages would depend on assortative mating in which the evolving goby fishes would prefer to mate with other fish that preferred to spawn in the same area of rare coral.
See also
- Disassortative mating
- Intra-species recognitionIntra-species recognitionIntra-species recognition is recognition by a member of a species of a conspecific . In many species, such recognition is necessary for procreation....
- KoinophiliaKoinophiliaKoinophilia is a term used by biologist Johan Koeslag, meaning that when sexual creatures seek a mate, they prefer that mate not to have any unusual, peculiar or deviant features....
- Balancing selectionBalancing selectionBalancing selection refers to a number of selective processes by which multiple alleles are actively maintained in the gene pool of a population at frequencies above that of gene mutation. This usually happens when the heterozygotes for the alleles under consideration have a higher adaptive value...
- Directional selectionDirectional selectionIn population genetics, directional selection is a mode of natural selection in which a single phenotype is favored, causing the allele frequency to continuously shift in one direction...
- Disruptive selectionDisruptive selectionDisruptive selection, also called diversifying selection, describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups...
- Negative selection (natural selection)Negative selection (natural selection)In natural selection, negative selection or purifying selection is the selective removal of alleles that are deleterious. This can result in stabilizing selection through the purging of deleterious variations that arise....
- HypergamyHypergamyHypergamy is the act or practice of seeking a spouse of higher socioeconomic status, or caste status than oneself....