Some breeds are almost outside of homogeneity and common origin criteria, based on a desire to organize the breeding of a species. This is the case of certain breeds of cows that have been "created" by merging several local races, or the horse and told Saddle French Saddle Pony, for which permits limited background and crosses but heterogeneous (TICA ragdoll breeders).
These breeds are formed with use objectives, production, and to collect and identify a type of animal. They can be called later be "closed" to new contributions or instead be constantly fed with products of first generation crosses of other races, as is the case of saddle ponies from pony breeds and arabian.
This article relates more particularly to use of word "race" to refer to groups of same species. Botanical nomenclature and mycological hence the term "race" is not a codified taxonomic rank, we speak of variety. It remains possible to use the word "animal variety" 4 to designate a selected domestic animal population consists of a fraction of animals of a species that special treatment selection have resulted distinguished from other animals of case by a small number of characters whose enumeration defines the model.
Drafting laws of heredity based on the work of Gregor Mendel used to connect a breed with a particular genotype. To understand this relationship, it is necessary to distinguish two notions: observable characters (the individual's phenotype) and the information carried by the genome (genotype of individual).
Individuals of subspecies always remaining interbreeding, often observed within a species of being isolated populations, sometimes with morphological differences, sometimes ecological differences (ecotypes) no necessary correlation with their condition genetic differentiation.
The terms "pure race" or "racial fixed" often do not correspond to an objective reality given the history of races, and selection which they are subject. The horse says thoroughbred for example, is a cross between British mares and stallions beards, from the Maghreb, and probably of Arabian horses. However, these terms can be taken with a relative sense, and there are homogeneous and ancient races.
For animal species used in breeding or plant species cultivated for food, industrial, ornamental, the selection pressure exerted by the man leads to greater homogeneity (relative to genes governing the desired phenotypes) of population and correspondingly to a loss of genetic diversity, which weakens vis-a-vis population aggression of any kind, such as disease. Commercial requirements lead to many standard set of breeds or varieties corresponding to different needs; well, animals or plants which do not correspond to standard of a race (or variety) are not involved in reproduction. The microorganisms used in industry have also been long since similar selections (eg yeast).
Recently, genetic engineering to modify the genes from one species to create genetically modified or transgenic species, including the new properties that meet the needs of those who exploit them. In classification of living things, the species (that is to say, a set of individuals generally interbreeding) is the last subdivision (or taxon) unanimously accepted.
These breeds are formed with use objectives, production, and to collect and identify a type of animal. They can be called later be "closed" to new contributions or instead be constantly fed with products of first generation crosses of other races, as is the case of saddle ponies from pony breeds and arabian.
This article relates more particularly to use of word "race" to refer to groups of same species. Botanical nomenclature and mycological hence the term "race" is not a codified taxonomic rank, we speak of variety. It remains possible to use the word "animal variety" 4 to designate a selected domestic animal population consists of a fraction of animals of a species that special treatment selection have resulted distinguished from other animals of case by a small number of characters whose enumeration defines the model.
Drafting laws of heredity based on the work of Gregor Mendel used to connect a breed with a particular genotype. To understand this relationship, it is necessary to distinguish two notions: observable characters (the individual's phenotype) and the information carried by the genome (genotype of individual).
Individuals of subspecies always remaining interbreeding, often observed within a species of being isolated populations, sometimes with morphological differences, sometimes ecological differences (ecotypes) no necessary correlation with their condition genetic differentiation.
The terms "pure race" or "racial fixed" often do not correspond to an objective reality given the history of races, and selection which they are subject. The horse says thoroughbred for example, is a cross between British mares and stallions beards, from the Maghreb, and probably of Arabian horses. However, these terms can be taken with a relative sense, and there are homogeneous and ancient races.
For animal species used in breeding or plant species cultivated for food, industrial, ornamental, the selection pressure exerted by the man leads to greater homogeneity (relative to genes governing the desired phenotypes) of population and correspondingly to a loss of genetic diversity, which weakens vis-a-vis population aggression of any kind, such as disease. Commercial requirements lead to many standard set of breeds or varieties corresponding to different needs; well, animals or plants which do not correspond to standard of a race (or variety) are not involved in reproduction. The microorganisms used in industry have also been long since similar selections (eg yeast).
Recently, genetic engineering to modify the genes from one species to create genetically modified or transgenic species, including the new properties that meet the needs of those who exploit them. In classification of living things, the species (that is to say, a set of individuals generally interbreeding) is the last subdivision (or taxon) unanimously accepted.
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