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Hybrid incompatibility occurs when the offspring of two closely related species are not viable or suffer from infertility. Charles Darwin posited that hybrid incompatibility is not a product of natural selection, stating that the phenomenon is an outcome of the hybridizing species diverging, rather than something that is directly acted upon by selective pressures. [4]
In humans, barring intersex conditions causing aneuploidy and other unusual states, it is the male that is heterogametic, with XY sex chromosomes.. Haldane's rule is an observation about the early stage of speciation, formulated in 1922 by the British evolutionary biologist J. B. S. Haldane, that states that if — in a species hybrid — only one sex is inviable or sterile, that sex is more ...
This is a list of genetic hybrids which is limited to well documented cases of animals of differing species able to create hybrid offspring which may or may not be infertile. Hybrids should not be confused with genetic chimeras , such as that between sheep and goat known as the geep .
The hybrids between both species are not sterile, in the sense that they produce viable gametes, ovules and spermatozoa. However, they cannot produce offspring as the sperm of the hybrid male do not survive in the semen receptors of the females, be they hybrids or from the parent lines.
Genetic incompatibility describes the process by which mating yields offspring that are nonviable, prone to disease, or genetically defective in some way. In nature, animals can ill afford to devote costly resources for little or no reward, ergo, mating strategies have evolved to allow females to choose or otherwise determine mates which are more likely to result in viable offspring.
Human-alien hybrids fill science fiction stories, and the most famous of these is Mr. Spock from Star Trek — the logical science officer of the starship Enterprise.
Heterospecific mating between the gray treefrog and Cope’s gray treefrogs also can form an infertile hybrid which is highly costly to both parents due to the wastage of gametes. [8] Chemical signalling in ticks – Female ticks produce a pheromone that is a species-specific signal to attract conspecific males that are attached to the host ...
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