Where are Horses from

What's with the horses?

The horse bones from this period, the late Pleistocene, can be found in Europe, Eurasia, Beringia and North America. Think of a world where horses of all colours, shapes and sizes travelled the world, some barely bigger than a small dog. Surprising story of America's wild horses Today's horses, lemurs and donkeys are part of the Equus species, the only remaining species in a once multifaceted familiy, the Equidae. On the basis of fossilized recordings, the species seems to have emerged about 4 million years ago in North America and expanded to Eurasia 2 to 3 million years ago (probably by traversing the Bering country bridge).

After this initial migration, further western migration to Asia and repatriation to Northern America followed, as well as the extinction of Equus specimens in Northern America. Last pre-historic horses from the United States of America passed away 13,000 to 11,000 years ago, at the end of the Pleistocene, but by then Equus had expanded to Asia, Europe and Africa.

On palaeontological soil, ponies that could be identified as varieties of the present-day equine genus came from North America 1 million to 2 million years ago. But when Linnaeus gave the name to the breed, E. caballus, he only had the pet in his mind. His next savage progenitor may have been tartan, often referred to as E. ferus, but there is no proof that tartan was any other kind.

However, the home made animal was probably not created in a unique place and at a unique moment, but was raised by Euro-Asian shepherds from several game types. Over the last few years, biomolecular research has provided new instruments for studying the relationship between equine and equine specimens and their related relations to each other. Ann Forstén of the Zoological Institute of the University of Helsinki estimates that E. Caballus was formed about 1.7 million years ago in North America on the basis of gene expression mutations for Mitochondrial Genetic Material (mtDNA).

Even more precise is her interpretation of E. Iambei, the Yukon-Pferd, which was the youngest Equus breed in North America before the Equus disappeared from the mainland. Your study of E. llambei mtDNA (preserved in Alascan permafrost) showed that the strain is equivalent to E. caballus in genetic terms.

Michael Hofreiter, Department of Evolutionary Genetics at the Max Planck Institute in Leipzig, Germany, supports this finding by stating that the variations lie within those of contemporary horses. Domestic horses are known to have been imported to North America, beginning with the Spaniards' capture, and escape horses later spreading to the American Great Plains.

Usually such game-horses, that survived today, are called "wild" and are considered as obtrusive, exotic creatures, in contrast to the indigenous horses, that became extinct at the end of the Pleistocene. As E. caballus they are not so strange. Horses were domestically farmed before their reintroduction, which means little from a biologic point of view.

In fact, hometication has changed them little, as can be seen from how quickly horses return to old natural behaviour models. Mongolia's hippopotamus (E. prizewalskii or E. caballus prizewalskii) vanished a hundred years ago from its natural environment in Mongolia and North China.

In the 90s, excess wildlife was set free and is now repopulating part of their home territory in Mongolia and China. Or are they a re-introduced indigenous or not? How does their aspiration to end-emism differ from that of E. caballus in North America, apart from the length and level of imprisonment?

In the United States, the U.S. is generally classified as non-native by most U.S. and U.S. government agency responsible for keeping animals in the wild, whose statutory mission is typically to conserve indigenous animals and avoid non-indigenous animals having environmentally damaging impacts. However, the two keys to the definition of an organism as a indigenous specie are where it originates and whether it has developed with its environment or not.

E. Caballus can say to do both in North America. A good reason can therefore be put forward that it too should be protected as a local animal species. Kirkpatrick, who received his PhD in reproduction psychology from the College of Veterinary Medicine at Cornell University, completed his studies in feral horse fecundity monitoring.

M. Fazio, a research associate at the Science and Conservation Center, received a PhD in Environment Studies from Texas A&M University. She is interested in reproductionhysiology, the surveillance of feral horses and the equine evolvement.

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