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Re: [RC] Wild Horses Letter in NY Times..on the mark - heidiSomeone passed the me on a paper of a study that claims that the wild horses are in fact the same genetically as those that evolved in the North America which calls into question the assumption that the wild horses are all feral. An excerpt below along with the references.Horses have traditionally been considered non-native, "feral," and exotic in North America. This was based on the argument that E. caballus (or the caballoid horse) was not present on this continent when horses disappeared 11,000 to 13,000 years ago. The horse brought back by the Spanish was thought to be a different species than the species present in North America at extinction. However, the relatively new (27-year-old) field of molecular biology, using mitochondrial DNA analysis, has recently found that the modern horse, E. caballus, is genetically identical to E. lambei, a horse, according to fossil records, that represented the most recent Equus species in North America prior to extinction. Not only is E. caballus genetically equal to E. lambei, but no evidence exists for the origin of E. caballus anywhere except North America.[5] Somebody is misinterpreting the meaning of mtDNA, I'd suspect. First of all, there are several types of mtDNA among Equus caballus. This is how different dam lines can be sorted out. That said, since mtDNA could well go back several thousand years, it is also not untoward to think that different subspecies could easily share the same mtDNA, even if there has been considerable change in their genetic makeup--enough to make them not the same critter at all. The dispute is not about where E. caballus originated--the fact is that equids became extinct on this continent, were extinct for several thousand years, and then were reintroduced as feral animals after domestication had occurred. Heidi =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Ridecamp is a service of Endurance Net, http://www.endurance.net. Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp Ride Long and Ride Safe!! =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
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