Researchers discovered this finding by comparing the skulls of domesticated dogs to those of different species that also belong to the Carnivora group, which includes cats, bears and even walruses. They found that dogs’ skull shapes were extremely varied when compared to other animals in the group and also when compared to other dog breeds. The article gives the example of a Collie’s skull, which was found to be shaped more differently from the skull of a Pekingese than a cat’s skull is from a walrus’s.
A lot of this variation is due to the selective breeding of dogs, explained the researchers, which has led to skull shapes that are “entirely novel," thereby taking Charles Darwin’s theory of evolution by natural selection to an new level.
“Domestic dogs are boldly going where no self-respecting carnivore ever has gone before,” Dr. Chris Klingenberg, a biologist and coauthor of the report, explained to ScienceDaily.
Though this evolutionary leap has led to a lifetime of luxuries such as canned dog food, sleeping on the sofa and, of course, unconditional love, some domestic dogs probably wouldn’t survive very well in the wild because these biological variations that make them seem cuter, may also hinder them in a more challenging setting. For example, the pushed-in face of a pug can make even tough guys melt, but it also means that the dog has a shorter breathing passage and is, therefore, highly susceptible to overheating in hot weather.
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