Reproductive isolation

reproductively isolatedisolating mechanismsisolating mechanismBarriers to reproductionreproductive barriersbarriers to hybridizationbehavioral isolationbut not with othersecological isolationgenetic differentiation
The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, behaviors and physiological processes critical for speciation.wikipedia
261 Related Articles

Speciation

divergedspeciatedtrichotomy
The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, behaviors and physiological processes critical for speciation.
Rapid sympatric speciation can take place through polyploidy, such as by doubling of chromosome number; the result is progeny which are immediately reproductively isolated from the parent population.

Allopatric speciation

allopatricvicarianceallopatry
Zoologist Ernst Mayr classified the mechanisms of reproductive isolation in two broad categories: pre-zygotic for those that act before fertilization (or before mating in the case of animals) and post-zygotic for those that act after it. The mechanisms are genetically controlled and can appear in species whose geographic distributions overlap (sympatric speciation) or are separate (allopatric speciation).
The barriers prevent the exchange of genetic information between the two populations leading to reproductive isolation.

Hybrid (biology)

hybridhybridshybridization
The reason for the absence of inter-species mating is that B. americanus mates in early summer and B. fowleri in late summer.
Species are reproductively isolated by strong barriers to hybridisation, which include morphological differences, differing times of fertility, mating behaviors and cues, and physiological rejection of sperm cells or the developing embryo.

Natural selection

selectionselectiveselected
Pre-zygotic isolation mechanisms are the most economic in terms of the natural selection of a population, as resources are not wasted on the production of a descendant that is weak, non-viable or sterile.
Ernst Mayr recognised the key importance of reproductive isolation for speciation in his Systematics and the Origin of Species (1942).

Ernst Mayr

MayrMayr, ErnstMayr E.
Zoologist Ernst Mayr classified the mechanisms of reproductive isolation in two broad categories: pre-zygotic for those that act before fertilization (or before mating in the case of animals) and post-zygotic for those that act after it. The mechanisms are genetically controlled and can appear in species whose geographic distributions overlap (sympatric speciation) or are separate (allopatric speciation).
He maintained that factors such as reproductive isolation had to be taken into account.

Evolution

evolvedtheory of evolutionevolutionary theory
The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, behaviors and physiological processes critical for speciation.
Barriers to reproduction between two diverging sexual populations are required for the populations to become new species.

Sympatric speciation

sympatricsympatrysympatrically
Zoologist Ernst Mayr classified the mechanisms of reproductive isolation in two broad categories: pre-zygotic for those that act before fertilization (or before mating in the case of animals) and post-zygotic for those that act after it. The mechanisms are genetically controlled and can appear in species whose geographic distributions overlap (sympatric speciation) or are separate (allopatric speciation).
He figured that if two ecological niches are occupied by a single species, diverging selection between the two niches could eventually cause reproductive isolation.

Species

specificspecific namespecific epithet
They prevent members of different species from producing offspring, or ensure that any offspring are sterile.
Speciation depends on a measure of reproductive isolation, a reduced gene flow.

Sympatry

sympatricsympatricallysyntopic
A large variety of mechanisms have been demonstrated to reinforce reproductive isolation between closely related plant species that either historically lived or currently live in sympatry.
Such speciation may be a product of reproductive isolation – which prevents hybrid offspring from being viable or able to reproduce, thereby reducing gene flow – that results in genetic divergence.

Interploidy hybridization

interploidal crossesinterploidy crosses
The failure of endosperm development and its subsequent abortion has been observed in many interploidal crosses (that is, those between populations with a particular degree of intra or interspecific ploidy), and in certain crosses in species with the same level of ploidy.
This reproductive bottle neck leads to a phenomenon called triploid block.

Theodosius Dobzhansky

DobzhanskyDobzhansky, TheodosiusDobzhansky Award for Outstanding Contributions to Behavior Genetics
The Dobzhansky-Muller model proposes that reproductive incompatibilities between species are caused by the interaction of the genes of the respective species.
On the basis of his experiments, he articulated the idea that reproductive isolation can be caused by differences in presence of microbial symbionts between populations.

Species complex

species groupsuperspeciescryptic species
For example, in the semi-species of the group D. paulistorum the hybrid females are fertile but the males are sterile, this is due to the presence of a Wolbachia in the cytoplasm which alters spermatogenesis leading to sterility.
They are identified by the rigorous study of differences between individual species, making use of minute morphological details, tests of reproductive isolation, or DNA-based methods such as molecular phylogenetics or DNA barcoding.

Reinforcement (speciation)

reinforcementspeciation by reinforcementreinforcement of reproductive barriers
Namely, if selection reinforces the degree of reproductive isolation that exists between two species due to the poor adaptive value of the hybrids, it is expected that the populations of two species located in the same area will show a greater reproductive isolation than populations that are geographically separated (see reinforcement).
Reinforcement is a process of speciation where natural selection increases the reproductive isolation between two populations of species.

Species problem

biological species conceptspecies conceptgood species
Species problem
There is a continuum from reproductive isolation with no interbreeding, to panmixis, unlimited interbreeding.

History of evolutionary thought

evolutionary thoughtevolutionevolutionary theory
History of evolutionary thought
This form of speciation occurs when the geographical isolation of a sub-population is followed by the development of mechanisms for reproductive isolation.

Physiology

physiologistphysiologicalphysiologically
The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, behaviors and physiological processes critical for speciation.

Offspring

broodprogenybroods
They prevent members of different species from producing offspring, or ensure that any offspring are sterile.

Gene flow

geneflowgenetic exchangemigration
These barriers maintain the integrity of a species by reducing gene flow between related species.

Fertilisation

fertilizationconceptionfertilized
Zoologist Ernst Mayr classified the mechanisms of reproductive isolation in two broad categories: pre-zygotic for those that act before fertilization (or before mating in the case of animals) and post-zygotic for those that act after it. The mechanisms are genetically controlled and can appear in species whose geographic distributions overlap (sympatric speciation) or are separate (allopatric speciation).

Mating

matematescopulation
Zoologist Ernst Mayr classified the mechanisms of reproductive isolation in two broad categories: pre-zygotic for those that act before fertilization (or before mating in the case of animals) and post-zygotic for those that act after it. The mechanisms are genetically controlled and can appear in species whose geographic distributions overlap (sympatric speciation) or are separate (allopatric speciation).

Animal

animalsmetazoanmetazoa
Zoologist Ernst Mayr classified the mechanisms of reproductive isolation in two broad categories: pre-zygotic for those that act before fertilization (or before mating in the case of animals) and post-zygotic for those that act after it. The mechanisms are genetically controlled and can appear in species whose geographic distributions overlap (sympatric speciation) or are separate (allopatric speciation).

Genetics

geneticgeneticistgenetically
Zoologist Ernst Mayr classified the mechanisms of reproductive isolation in two broad categories: pre-zygotic for those that act before fertilization (or before mating in the case of animals) and post-zygotic for those that act after it. The mechanisms are genetically controlled and can appear in species whose geographic distributions overlap (sympatric speciation) or are separate (allopatric speciation).

Habitat

habitatsmicrohabitatnatural habitat
The types of barriers that can cause this isolation include: different habitats, physical barriers, and a difference in the time of sexual maturity or flowering.

Sexual maturity

sexually maturemature sexuallymaturity
The types of barriers that can cause this isolation include: different habitats, physical barriers, and a difference in the time of sexual maturity or flowering.

Stickleback

sticklebacksBrook sticklebackGasterosteidae
An example of the ecological or habitat differences that impede the meeting of potential pairs occurs in two fish species of the family Gasterosteidae (sticklebacks).