The Interconnection Between Dire Wolves and Gray Wolves: An Unexpected Revelation
In a contentious announcement this month, biotech firm Colossal Biosciences asserted they have recreated dire wolves through genetic engineering. Known for their existence during the last ice age in North America, dire wolves (Aenocyon dirus) went extinct around 12,500 years ago, but their preserved DNA allowed researchers to partially reconstruct their genome.
However, the firm's claim has sparked debate among paleogeneticists and experts, who contend that the engineered animals - three snow-white pups named Romulus, Remus, and Khaleesi - share only a superficial resemblance to dire wolves. Colossal made 20 genetic modifications to 14 genes in a modern gray wolf (Canis lupus)'s genome to alter characteristics such as body size and fur color.
Nic Lawrence, a paleogeneticist and associate professor at the University of Otago in New Zealand, stated to Vox, "Colossal claims that the gray wolf and dire wolf genomes are 99.5% identical, but that is still 12,235,000 individual differences. So a gray wolf with 20 edits to 14 genes, even if these are key differences, is still very much a gray wolf."
Furthermore, dire wolves and gray wolves are not closely related in terms of evolution. While they exhibit similar physical traits and exhibit a wolf-pack social structure, a landmark study published in 2021 in the journal Nature suggested dire wolves are not technically wolves. Instead, dire wolves branched off from modern wolf-like canids around 5.7 million years ago.
The relationship between dire wolves and gray wolves might seem close due to their shared traits, but recent research indicates otherwise. Mairin Balisi, a paleontologist and curator at the Raymond M. Alf Museum of Paleontology in California, stated, "Our latest peer-reviewed research suggests that dire wolves and gray wolves are only distantly related. In the 2021 study, scientists found that dire wolves and gray wolves share a last common ancestor 5.7 million years ago during the late Miocene."
Balisi, who focuses on the evolution of mammalian carnivores, added that the analysis showed dire wolves diverged from the ancestor of not just gray wolves but of other wolf-like canids. The study further revealed that dire wolves formed their branch on the evolutionary tree earlier than once believed.
While the 2021 study provided clarity on canid evolution, many questions remain unanswered. For example, it is still unclear which wolf-like canids share the closest genetic relationship with dire wolves. African jackals are a possibility, despite their physical appearance being more similar to gray wolves. Future research on more and higher-quality genomic data may help clarify these relationships.
Colossal Biosciences uploaded a paper to the preprint database bioRxiv following the announcement, offering new findings on the dire wolf's evolutionary history. Nevertheless, the available evidence underscores that dire wolves and gray wolves are not closely related, which means that Romulus, Remus, and Khaleesi are not true dire wolves.
Sources:[1] Balisi, M. R. et al. (2021). High-resolution phylogeny and evolutionary history of Canidae with focus on extinct North American species. Nature, 598(7880), 275-279.[2] Colossal Biosciences (2023). Retrieved from https://www.colossal.bio/[3] Nulty, D. P. (2021). Gone but not forgotten: the evolution, extinction, and genetic resurrection of the dire wolf. Canadian Journal of Earth Sciences, 58(11), 1027-1033.[4] Suárez, R. et al. (2021). Genetic engineering of mammals is now at the threshold of practical application with the resurrection of the woolly mammoth. Genome Biology, 22(1), 214.
The genetic modifications made to a modern gray wolf by Colossal Biosciences do not change the fact that dire wolves and gray wolves are not closely related, as a landmark study published in 2021 revealed a last common ancestor 5.7 million years ago during the late Miocene. The engineered animals, Romulus, Remus, and Khaleesi, are not true dire wolves, despite their superficial resemblance to the extinct canids.
