A Scientific Milestone
Published 8/4/2025
On October 1, 2024, biotechnology firm Colossal Biosciences announced the birth of two genetically engineered wolves named Romulus and Remus. Marketed as a breakthrough in the revival of extinct species, these animals were created using advanced gene-editing technologies and DNA derived from fossilized remains believed to belong to the extinct dire wolf (Aenocyon dirus), which last roamed North America around 10,000 years ago.
The wolves were developed using ancient DNA samples, including a 13,000-year-old tooth found in Ohio and a 72,000-year-old ear bone discovered in Idaho. By identifying and editing roughly 20 genetic markers across 14 genes that differentiate dire wolves from modern gray wolves, scientists introduced these traits into gray wolf embryos using CRISPR-Cas9 gene-editing tools. The embryos were then implanted into surrogate domestic dogs, leading to the successful birth of Romulus and Remus via planned cesarean delivery.
Science vs. Authenticity
Colossal Biosciences refers to the wolves as the first living dire wolves in over ten millennia. However, not everyone in the scientific community agrees. Critics suggest that Romulus and Remus are genetically modified gray wolves rather than true de-extincted specimens. This is largely because the process did not involve cloning directly from an intact dire wolf genome, but instead relied on identifying and replicating specific traits.
The debate centers on what constitutes “de-extinction.” Is mimicking an ancient species’ appearance and behavior sufficient, or must the exact genome be recreated? As it stands, Romulus and Remus are best described as genetic approximations rather than literal re-creations.
Ethical and Ecological Implications
The project has sparked wide-ranging discussions, drawing comparisons to the cautionary tale told in Jurassic Park. Ethical concerns include the treatment of the animals, the risks of unforeseen ecological consequences, and the broader question of whether humans should interfere with extinct species.
To address these concerns, Colossal Biosciences has confirmed that the wolves will live in a secure 2,000-acre ecological preserve, monitored by veterinary staff and scientists. There are no current plans to release them into the wild, and the company insists their primary goal is scientific research and ecological education.
What’s Next?
Romulus and Remus represent a bold step into the future of biotechnology and conservation science. Whether or not they are considered “true” dire wolves, their existence marks a new chapter in humanity’s ability to manipulate and preserve the natural world.
As we continue to explore the limits of genetic engineering, the birth of these animals prompts a vital conversation: Just because we can bring species back—should we?
