Encyclopedia  |   World Factbook  |   World Flags  |   Reference Tables  |   List of Lists     
   Academic Disciplines  |   Historical Timeline  |   Themed Timelines  |   Biographies  |   How-Tos     
Sponsor by The Tattoo Collection
Hybrid
Main Page | See live article | Alphabetical index

Hybrid

This article is about a biological term. See hybrid (disambiguation) for other meanings.

In biology, hybrid has two meanings. The first meaning is either the offspring of two different species, or of two different genera. The second meaning of "hybrid" is crosses between populations or cultivars ("cultivated varieties") of a single species. This second meaning is often used in plant breeding. Hybrids between species of the same genus are sometimes known as interspecific hybrids or crosses. Hybrids between different genera are sometimes known as intergeneric hybrids.

Ernst Mayr wrote of Gregor Mendel, "He was uncertain about the nature of the kinds of peas he crossed, and, like most plant breeders, he called heterozygotes "hybrids." When he tried to confirm the laws he had found by using "other hybrids" that were actually real species hybrids, he failed. The use of the same term "hybrid" for two entirely different biological phenomena thwarted his later efforts." (This is Biology, 1997, p58f).

Some dog hybrids (used in sense two, above), are becoming increasingly popular and are being bred selectively.

Plant hybrids, especially, may or may not be stronger than either parent variety, a phenomenon which when present is known as hybrid vigour. To create specialised plants is called cross-fertilisation. In animals, hybrids often manifest reduced fertility or, like the mule are sterile.

Some interspecies hybrids are:

Hybrids should not be confused with chimaeras.