Dedomestication
Under feral animal or Entdomestizierung , commonly known as naturalizing , refers to the reversal of the domestication ( domestication ), the emergence of a so-called Paria form of domestic animals . It contrasts with the wild form , which only denotes animals that are not domesticated by humans.
In the case of dedomestication, wilding is brought about by natural selection . Another process is the targeted introduction of domestic animals to their wild forms through human breeding ( breeding of images ).
process
While animals survive and reproduce in nature, which are well adapted to the prevailing environmental conditions, humans specifically select particularly sociable, particularly conspicuous or particularly productive animals for breeding in the course of domestication . Thus, the selection conditions differ in nature and in the care of humans, which is why animals in domestication change in terms of appearance, behavior and genetics . Dedomestication occurs when a population of domestic animals leaves human custody and is henceforth exposed to natural selection .
Characteristics preferred by humans, such as sociability, special color variations, productivity with regard to meat or milk , extravagant physical characteristics, etc., are meaningless or obstructive and are selected out by predatory pressure and lack of food, which requires energy savings. Those individuals who show escape, defensive or hunting behavior, have an inconspicuous camouflage color or have a frugal physique have an advantage . Provided that specimens with such alleles are still present in the free- living domestic animal population, they will prevail more or less quickly, and after a period of time that depends on the duration of generation and selection pressure, a pariah form will stabilize, which is adapted to the respective living conditions. Dedomestication does not automatically create a population that corresponds to the former wild form of the domestic animal. Not all traits of the wild form are present in the left pet population or can be reversed, and some traits that appeared after domestication need not necessarily have a fitness- reducing effect. Feral domestic dogs, for example, do not necessarily become “wolves”, as the example of the dingoes or the Carolina dogs shows. Also, in the case of large animals, a camouflage color is not absolutely essential for life, which is why feral ungulate populations can sometimes be very heterogeneous in terms of color and can also have the piebald markings typical of pets (e.g. mustangs ).
Examples
There are a number of examples of dedomestication, mainly in mammals . They are either pets that accidentally escaped and feral, or they were deliberately abandoned - for example for hunting or nature conservation purposes . The wilding of pets is sometimes environmentally problematic, since z. For example, wild domestic cats threaten the purity and availability of habitat of the European wildcat .
Wild rabbits
The wild rabbit , Oryctolagus cuniculus , was originally found mostly only on the Iberian Peninsula, but was introduced to various regions of Europe in the course of antiquity and the Middle Ages. Domestic rabbits continued to be released in Australia , New Zealand , South Africa, and North and South America , where they developed a phenotype very similar to that of the wild .
Mustangs and other feral domestic horses
In the North American prairie are Mustangs known since the 16th century. These are descendants of European domestic horses that escaped and feral. Mustangs are small, tough, compact ponies cm 140-150 Height reach. They are very frugal and have a stubborn and independent character. Their exterior (appearance) includes hard and small hooves, a stable foundation, rams head , a low neck, little withers and a strong back with sloping croup . The coat colors and markings of the Mustangs are very heterogeneous and do not differ from those of most other domestic horse breeds.
In Europe, too, there are wild domestic horses of various breeds and in various regions. Examples of these are the Exmoor ponies in the Exmoor National Park , Pottoks in the Basque Country , Retuerta in the Coto de Doñana National Park , Koniks in Oostvaardersplassen , Giara horses in some regions of Sardinia and a few others.
In the case of semi-wild domestic horses it can be observed that, unlike other grazing animals, their nature does not easily go wild. In contrast to Przewalski horses , semi-wild domestic horses are usually just as easy to handle as horses that are kept in the usual way.
Wild domestic cattle
There are a variety of wild domestic cattle populations . For example, the Monstrenca cattle in Doñana National Park , the Betizu and Divjaka cattle in Spain and wild Camargue cattle in southern France. There are also wild domestic cattle populations on islands near New Zealand, the Falkland Islands and also on the Seychelles . In Portugal, feral herds of the primitive Maronesa breed exist in mountainous regions . From the Texas Longhorn cattle there are u. a. a wild population in the Wichita Mountains Wildlife Refuge . Chillingham cattle, which are very rare today, have been grazing wildly for centuries in Northumberland , England, with no significant human influence . Heck cattle have been living in Oostvaardersplassen since 1992 without additional feeding in winter or stock control. The animals are only shot when they are severely weakened in order to prevent avoidable suffering.
With the exception of the Chillingham cattle, Betizuaks, Maronesa or Camargue cattle, most feral domestic cattle are very heterogeneous in terms of coat color or horn shape, as there is usually no hunting pressure from predators. It has been found that behavioral behavior makes cattle feral. A few weeks away from human care are enough for cattle to show their natural behavior again.
Feral domestic dogs
Dingoes are descended from native indigenous domestic dogs that were feral in Australia thousands of years ago and have developed into a homogeneous pariah form adapted to their habitat, which is currently threatened by interbreeding with other domestic dogs. The biology of these dedomesticated domestic dogs has been well researched. Dingoes have been the "new" larger carnivores in Australia for millennia, occupying a niche that has been vacated by the disappearance of predatory poults such as the marsupial lion and the pouch wolf .
Another pariah dog is the Carolina Dog in the southeastern United States, which has only been known for a relatively short time and is not unlike the dingo.
Feral domestic pigs
In North America there has been a population of feral domestic pigs known since the 16th century , the so-called razorbacks . Through natural selection, these have acquired a resemblance to the Eurasian wild boar , from which they descended as domestic pigs. In some cases, however, razorbacks have mixed with imported wild boars.
European mouflon
The westernmost populations of the mouflon were found on the European continent at the earliest 5000 years ago. Features such as the reduced brain volume and the high proportion of hornless females in the European mouflon suggest that this is not a real wild animal, but the offspring of feral, original domestic sheep . Accordingly, the European mouflon would be a pariah form. In addition, various original domestic sheep have repeatedly been introduced into the European mouflon population, which is why this can sometimes differ from region to region.
Feral domestic pigeons
House pigeons are domesticated rock pigeons , the city pigeon is a feral form of the house pigeon. They are by no means homogeneous in their appearance. There are numerous animals that are very similar to the wild form. These have a blue-gray plumage with two almost black stripes (technically "blue with black bands") or many small dark spots on the wing (technically blue-hammered), but there are also ashen (technically "red pale") animals with smaller or larger ones white spots in the otherwise colored plumage or black and white piebald color morphs . As a cultural follower , they occur on almost all continents and mainly prefer cities as living space.
literature
- Ilse Haseder , Gerhard Stinglwagner : Knaurs Großes Jagdlexikon , Weltbild, Augsburg 2000, keyword: Wilderness, ISBN 3-8289-1579-5 .
Web links
Individual evidence
- ↑ Haseder, p. 836.
- ^ Leo Linnartz, Renée Meissner: Rewilding horses in Europe. Background and guidelines - a living document. Publication by Rewilding Europe, Nijmegen (NL) 2014, ISBN 978-90-822514-1-8 PDF .
- ↑ a b c d Bunzel-Drüke, Finck, Kämmer, Luick, Reisinger, Riecken, Riedl, Scharf & Zimball: Wilde Weiden: Practical guidelines for year-round grazing in nature conservation and landscape development.
- ↑ Robert F. Schloeth : The social life of the Camargue cattle. Qualitative and quantitative studies of the social relationships - especially the social ranking - of the semi-wild French fighting cattle , Berlin 1959.
- ↑ Cis van Vuure: Retracing the aurochs - History, Morphology and Ecology of an extinct wild ox. 2005, ISBN 954-642-235-5 .