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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 .
A mule is a sterile hybrid of a male donkey and a female horse.Mules are smaller than horses but stronger than donkeys, making them useful as pack animals.. In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction.
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]
A form of hybrid speciation that is relatively common in plants occurs when an infertile hybrid becomes fertile after doubling of the chromosome number. Hybridization without change in chromosome number is called homoploid hybrid speciation. [1] This is the situation found in most animal hybrids.
Mature egg cells are produced by mitotic divisions, and these cells directly develop into embryos. In flowering plants, cells of the gametophyte can undergo this process. The offspring produced by apomictic parthenogenesis are full clones of their mother, as in aphids. [citation needed]
In the hybrids, specific gene products contributed by one of the parents may be inappropriately recognized as foreign and pathogenic, and thus trigger pervasive cell death throughout the plant. [68] In at least one case, a pathogen receptor, encoded by the most variable gene family in plants, was identified as being responsible for hybrid necrosis.
Such fusion of vegetative cells and subsequent parasexual mating with mitotic crossover may generate recombined hybrid cells. [148] For hybrid species to evolve, reproductive isolation against the parent species is required. The ease by which such reproductive isolation arises is thus also important for the rate at which stable hybrid species ...
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a different organism is called a ...