Nature reflects our nature
HYBRID ORGANISMS k | ltlaDa
In biology , a hybrid is an offspring of two animals or plants of different breeds , varieties , species , or genera . The term hybrid , therefore , has a wider application than the terms mongrel or crossbreed , which usually refer to animals or plants resulting from a cross between two races , breeds , strains or varieties of the same species .
Hybrids between different species within the same genus are sometimes known as interspecific hybrids or crosses . Mules , hinnies , and other normally sterile interspecific hybrids cannot produce viable gametes because the extra chromosome cannot make a homologous pair at meiosis , meiosis is disrupted , and viable sperm and eggs are not formed . Hybrids between different sub-species within a species are known as intraspecific . An example of an intraspecific hybrid is a hybrid between a Bengal tiger and an Amur ( Siberian ) tiger .
The process of hybridization is important biologically because it increases the genetic variation within a species , which is necessary for evolution to occur . If climatic or habitat conditions change , individuals with certain combinations may be eliminated , but others with different combinations will survive . The Lonicera fly is the first known animal species that resulted from Natural hybridization . Until the discovery of the Lonicera fly , this process was known to occur in nature only among plants .
Mule ( Male Donkey + Female Horse ) Liger ( Lion + Tiger )
SIBLING SPECIES ( Cryptic Species ): Two or more groups of organisms that cannot be readily distinguished by their appearance or other traditional taxonomic criteria but whose members cannot interbreed successfully ( reproductively isolated ). Sibling species may arise as a result of allopatric speciation through geographic isolation , parapatric speciation , or sympatric speciation . The important thing is to note is that sibling species are separate biological species . The biological species concept , proposed by Ernst Mayer in 1942 emphasizes reproductive isolation as the basis of defining a species .
Although they have been discovered in organisms from protozoans to elephants , they are probably best known and abundantly documented among the insects . As small organisms , insects can exploit a multitude of niches , changing physiologically and behaviorally during speciation while retaining their structural similarity . Sibling species can exist in different niches in the same community without appreciable differentiation in those morphological characters that are used by taxonomists in their classification .
Examples : Many North American species of cricket , occupying the same geographical range , can be distinguished only by their song . Malaria carrying mosquito of Europe , Anopheles maculipennis , and Anopheles atroparvus are morphologically similar and have the same group but they are reproductively isolated and they are unable to produce fertile hybrids .
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