002A-00 woolly mammoth
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Romulus and Remus are doing what puppies do: chasing, tussling, nipping, nuzzling. But there’s something very un-puppylike about the snowy white 6-month olds—their size, for starters. At their young age they already measure nearly 4 ft. long, tip the scales at 80 lb., and could grow to 6 ft. and 150 lb. Then there’s their behavior: the angelic exuberance puppies exhibit in the presence of humans—trotting up for hugs, belly rubs, kisses—is completely absent. They keep their distance, retreating if a person approaches. Even one of the handlers who raised them from birth can get only so close before Romulus and Remus flinch and retreat. This isn’t domestic canine behavior, this is wild lupine behavior: the pups are wolves. Not only that, they’re dire wolves—which means they have cause to be lonely.
The dire wolf once roamed an American range that extended as far south as Venezuela and as far north as Canada, but not a single one has been seen in over 10,000 years, when the species went extinct. Plenty of dire wolf remains have been discovered across the Americas, however, and that presented an opportunity for a company named Colossal Biosciences.
Relying on deft genetic engineering and ancient, preserved DNA, Colossal scientists deciphered the dire wolf genome, rewrote the genetic code of the common gray wolf to match it, and, using domestic dogs as surrogate mothers, brought Romulus, Remus, and their sister, 2-month-old Khaleesi, into the world during three separate births last fall and this winter—effectively for the first time de-extincting a line of beasts whose live gene pool long ago vanished. TIME met the males (Khaleesi was not present due to her young age) at a fenced field in a U.S. wildlife facility on March 24, on the condition that their location remain a secret to protect the animals from prying eyes.
The dire wolf isn’t the only animal that Colossal, which was founded in 2021 and currently employs 130 scientists, wants to bring back. Also on their de-extinction wish list is the woolly mammoth, the dodo, and the thylacine, or Tasmanian tiger. Already, in March, the company surprised the science community with the news that it had copied mammoth DNA to create a woolly mouse, a chimeric critter with the long, golden coat and the accelerated fat metabolism of the mammoth.
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