you will no doubt remember the dire wolves,
fearsome creatures, that grew up to 6 feet long, well they did actually exist, above two grey wolves (lower left) confront a pack of dire wolves
over a bison carcass in southwestern North America 15,000 years ago, (Illustration by Mauricio Anton / UCLA), they were real dogs that grew up to six feet long in
order to hunt the megafauna of North America tens of thousands of years ago, quite a few of their remains were preserved in the La Brea tar pits, dire
wolves were identified as a species in the 1850s, but now DNA analysis tells us
more about them. For example, they weren't really wolves, which I must admit I found surprising, after sequencing five genomes from dire wolf fossils between
50,000 and 13,000 years old, the researchers found that the animals belonged to
a much older lineage of dogs. Dire wolves, it now appeared, had evolved in the
Americas and had no close kinship with the grey wolves from Eurasia; the last
time grey wolves and dire wolves shared a common ancestor was about 5.7 million
years ago. The strong resemblance between the two, the researchers say, is a
case of convergent evolution, whereby different species develop similar
adaptations—or even appearances—thanks to a similar way of life. Sometimes such
convergence is only rough, such as both birds and bats evolving wings despite
their differing anatomy. In the case of dire and grey wolves, lives of chasing
large herbivores to catch some meat on the hoof resulted in two different canid
lineages independently producing wolf like forms, the DNA study is causing scientists to rethink how and why dire
wolves went extinct, and how they should be classified, you can read more about these monster that were at one time real live dogs at Scientific American, another case of seeing a monster in a movie, that was not a figment of a writers imagination.
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