Colossal Biosciences asserts that three recently born pups are dire wolves, but they are, in reality, genetically modified grey wolves designed to mimic the extinct species.
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*New Scientist: Bringing you insights from expert journalists on advances in science, technology, health, and the environment through articles and our magazine.* Colossal Biosciences presents genetically modified grey wolves Romulus and Remus.
A company named Colossal Biosciences claims to have resurrected an extinct species— the dire wolf. Their website states, "On October 1, 2024, for the first time in human history, Colossal successfully restored a once-eradicated species through the science of de-extinction. After a 10,000-year absence, our team is thrilled to return the dire wolf to its rightful role in the ecosystem." So, what's the reality behind this assertion? What's the latest development?:
Colossal is claiming that three genetically altered grey wolf pups—two males, Remus and Romulus, born in October, along with a female named Khaleesi born in January—are actually dire wolves. The company has also announced progress on creating woolly mice and nearly complete genomes of thylacines (Tasmanian tigers). What exactly is a dire wolf?: Dire wolves (Aenocyon dirus) were large canines that roamed the Americas until roughly 10,000 years ago. These creatures resembled oversized wolves with white fur and gained fame through the Game of Thrones television series, hence the name Khaleesi, after one of its main characters. So, is a dire wolf an extinct species of wolf?: Not quite. Although grey wolves and dire wolves were thought to be closely related due to their physical similarities, a 2021 study of ancient DNA revealed that they last shared a common ancestor about 6 million years ago. In fact, jackals, African wild dogs, and dholes are more closely related to grey wolves (*Canis lupus*) than dire wolves, despite any resemblance.
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Does this imply significant genetic differences between grey wolves and dire wolves?: Beth Shapiro from Colossal mentions that her team has sequenced the entire genome of the dire wolf, which will soon be publicly available. While she did not specify the exact number of differences, she stated that the two species share 99.5% of their DNA. Given that the grey wolf genome consists of around 2.4 billion base pairs, there are still millions of base pair differences to consider.
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