Breeding back
Breeding back is a form of
It must be kept in mind that a breeding-back breed may be very similar to the extinct wild type in phenotype, ecological niche, and to some extent genetics, but the gene pool of that wild type was different prior to its extinction. Even the superficial authenticity of a bred-back animal depends on the particular stock used to breed the new lineage. As a result of this, some breeds, like Heck cattle, are at best a vague look-alike of the extinct wild type aurochs, according to the literature.[1]
Background
The aim of breeding back programs is to restore the wild traits which may have been unintentionally preserved in the lineages of domesticated animals. Commonly, not only the new animal's phenotype, but also its ecological capacity, are considered in back-breeding projects, as hardy, "bred back" animals may be used in certain conservation projects. In nature, usually only individuals well suited to their natural circumstances will survive and reproduce, whereas humans select animals with additional attractive, docile or productive characteristics, protecting them from the dangers once found in their ancestral environment (predation, drought, disease, extremes of weather, lack of mating opportunities, etc.). In such cases, selection criteria in nature differ from those found in domesticated conditions. Because of this, domesticated animals often differ significantly in phenotype, behaviour and genetics from their wild forerunners. It is the hope of breeding-back programs to re-express, within a new breeding lineage, the wild, ancient traits that may have "lain buried" in the DNA of domestic animals.
In many cases, the extinct wild type ancestors of a given species are known only through skeletons and, in some cases, historical descriptions, making their phenotype poorly understood. Given that situation, there is currently no certainty of achieving success with a back-breeding attempt, and any results must be reviewed with great caution. In order to test genetic closeness, DNA (both mitochondrial and nuclear) of the breeding animals must be compared against that of the extinct animal.
Successful breeding back might be possible: humans have selected animals only for superficial traits, and as a rule did not intentionally change less-observable traits, such as metabolic biochemistry.[1] Further, since many domestic species show behaviours derived from their wild ancestors (such as the herding instinct of cattle or the social instincts of dogs), and are fit to survive outside the sphere of human interference (as evidenced by the many feral populations of various domestic animals), it can be presumed that "bred back" animals might be able to function like their wild ancestors.[1] For example, food preferences are assumed to be largely the same in domesticated animals as in their wild type ancestors.
Natural selection might serve as an additional tool in creating "authentic" robustness, "authentic" behaviour, and perhaps, the original phenotype as well. In some cases, a sufficient predator population would be necessary to enable such a selection process; in today's Europe, where many breeding-back attempts take place, this predator population is largely absent.
Use
Bred-back breeds are desirable in
Examples
Aurochs
Ideas for creating an
European wild horse
The Polish Konik horse is often erroneously considered the result of a breeding-back experiment to "recreate" the phenotype of the Tarpan. The Konik is actually a hardy landrace breed originating in Poland, which was called Panje horse before agriculturist Tadeusz Vetulani coined the name "Konik" in the 1920s. Vetulani started an experiment to reconstruct the Tarpan using Koniks; ultimately, his stock made only a minor contribution to the present-day Konik population.[2]
During the Second World War, the Heck brothers crossed Koniks with
Pigs
Quagga
The Quagga Project is an attempt, based in South Africa, to breed animals which strongly resemble the now-extinct quagga, a subspecies of the plains zebra which died out in 1883. Accordingly, the project is limited to selecting for the physical appearance of the original, as recorded by twenty-three mounted specimens, many contemporary illustrations, and a number of written accounts of the animals.[5]
The two most noticeable characteristics of the quagga, fewer stripes and a darker
The project has been criticized for its focus on the morphological characteristics of the quagga, as the extinct animal may have possessed unrecorded behavioral or non-visible traits that would be impossible to reliably breed back from plains zebras.[5]
Wolf
Although the
Although extinct,
The Dire Wolf Project, started in 1988, aims to bring back the look of the extinct prehistoric dire wolf by breeding different domestic dog breeds that resemble it.[8]
See also
References
- ^ ISBN 954-642-235-5
- ISBN 3-89432-913-0
- ^ Bunzel-Drüke, Finck, Kämmer, Luick, Reisinger, Riecken, Riedl, Scharf & Zimball: "Wilde Weiden: Praxisleitfaden für Ganzjahresbeweidung in Naturschutz und Landschaftsentwicklung
- ^ ISBN 978-1-55407-469-3.
- ^ a b c The Quagga Project explained
- ^ Heywood, Peter. "The Quagga and Science" (PDF). quaggaproject.org.
- .
- ^ "The Dire Wolf Project". www.direwolfproject.com. Archived from the original on 6 May 2020. Retrieved 16 July 2019.
Further reading
- Koene, P., & Gremmen, B. (2001). Genetics of dedomestication in large herbivores. In 35th ISAE Conference, Davis, California, 2001 (pp. 68–68).