What is genetic reproductive isolation?

What is genetic reproductive isolation?

: the inability of a species to breed successfully with related species due to geographical, behavioral, physiological, or genetic barriers or differences.

Is reproductive isolation the only way an individual species can develop?

Reproductive isolation is unique in evolution because it is not a trait possessed by members of a single species, but a composite character that is the joint property of a pair of species. A single species can be reproductively isolated only with respect to another.

Does reproductive isolation prevent gene flow?

They prevent members of different species from producing offspring, or ensure that any offspring are sterile. These barriers maintain the integrity of a species by reducing gene flow between related species. The mechanisms of reproductive isolation have been classified in a number of ways.

Is there a relationship between reproductive isolation and genetic distance?

In animals, the strength of reproductive isolation is generally positively associated with genetic distance and therefore presumably with time since species divergence (Coyne & Orr, 1989, 1997; Sasa, Chippindale & Johnson, 1998; Presgraves, 2002; Mendelson, 2003).

What are the types of reproductive isolation?

There are two main categories of reproductive isolation: prezygotic and postzygotic. Prezygotic isolation occurs before the formation of a zygote can take place. In most cases mating does not even occur. Forms of prezygotic isolation include spatial, behavioral, mechanical and temporal isolation.

What causes postzygotic reproductive isolation?

Postzygotic isolation occurs after members of two different species have mated and produced a zygote. The offspring of such a mating is called a hybrid. Hybrids are frequently unable to reproduce themselves, so the production of a hybrid is not considered a successful mating.

What factors contribute to reproductive isolation?

They result from natural selection, sexual selection, or even genetic drift:

• The evolution of different mating location, mating time, or mating rituals:
• Lack of “fit” between sexual organs:
• Offspring inviability or sterility:

Does reproductive isolation lead to speciation?

New species form by speciation, in which an ancestral population splits into two or more genetically distinct descendant populations. Speciation involves reproductive isolation of groups within the original population and accumulation of genetic differences between the two groups.

How does genetic analysis help with reproductive isolation?

Finally, genetic analysis can help localize small sections of chromosomes containing genes causing reproductive isolation, a necessary prelude to cloning and sequencing these genes.

Can a single species be reproductively isolated from another?

A single species can be reproductively isolated only with respect to another. Moreover, by its very nature, reproductive isolation is a trait that almost always involves epistatic interaction between alleles – but alleles occurring in different species.

Why does reproductive isolation occur in divergent evolution?

Because of divergent evolution, however, reproductive isolation continues to accumulate even after species cannot exchange genes, but such isolation is incidental to speciation. A proper study of speciation thus requires identifying the isolating mechanisms leading up to complete isolation (there may, of course, be more than one).

How does reproductive isolation lead to speciation in Drosophila?

Changes in sexual behavior can result in reproductive isolation between populations, leading to speciation. Studies of sexual behaviors in Drosophila species have led to different conclusions about the number of genes involved in speciation by this mechanism (Doi et al.