Dallas scientists claim to have resurrected an extinct dire wolf, but critics question whether the new pups can be considered true descendants the species that roamed North America thousands of years ago. 

Colossal Biosciences CEO Ben Lamm says the company successfully birthed three dire wolves using DNA from a 13,000-year-old tooth and a 72,000-year-old skull to analyze the full genome of the species and create three healthy dire wolf puppies, CBS and other news outlets reported earlier this week. Dire wolves have been extinct for more than 12,500 years.

The scientists named the three puppies Romulus, Remus, and Khaleesi. The first two male puppies were named after the founders of the city of Rome who, according to the legend, were raised by a female wolf. The female puppy was named after one of the Game of Thrones TV series characters because the show featured dire wolves.

However, critics think the scientists did not resurrect the species because the puppies do not resemble their alleged ancestors physically and genetically.

"All you can do now is make something look superficially like something else," said Vincent Lynch, a biologist at the University at Buffalo who was not involved in the research. "Whatever ecological function the dire wolf performed before it went extinct, it can't perform those functions" in today's environment.