002A-00 woolly mammoth
View More 
The idea of a “colossal dire wolf” has captured imaginations worldwide. But for Colossal Biosciences, this isn’t science fiction — it’s the careful application of biotechnology to restore traits of the long-lost dire wolf (Aenocyon dirus). Our pack of three pups — Romulus, Remus, and Khaleesi — represent a living demonstration of how ancient DNA research and modern gene editing can be combined to recreate extinct species.
As we look back at 2025, we’ll share two key updates: progress on our dodo initiative and highlights from our dire wolf “pupdates.” Together, these show both the scientific advances and the transparency that define our approach to de-extinction.
Advancing the Dodo Initiative
Colossal scientists achieved a historic breakthrough in avian genetics by successfully growing pigeon primordial germ cells (PGCs) in culture for the first time in history. PGCs are the embryonic precursors to sperm and eggs, and developing them in a laboratory setting is a necessary step toward editing genomes in birds.
This groundbreaking advancement allows us to introduce genetic edits derived from the Nicobar pigeon — the closest living relative of the extinct dodo (Raphus cucullatus). The long-term vision involves integrating these edited cells into chicken surrogates, creating a pipeline where future generations could carry dodo-like traits.
Beyond the PGC breakthrough, our avian team has established a flock of gene-edited chickens that will serve as potential surrogates for dodos and other endangered bird species. We’ve also generated new genomic resources for exotic and endangered pigeons, including high-quality reference genomes for the tooth-billed pigeon, Rodrigues solitaire, Nicobar pigeon, goura, and quail.
While still in development, these advances bring us measurably closer to producing the dodo and establish techniques that will benefit bird conservation more broadly. Every stride made in our dodo work sharpens our tools for preserving threatened avian species like the vulnerable Mauritian pink pigeon.
The Dire Wolves in 2025
Our dire wolf journey is evolving, pushing past genetics and into observing behavior, growth, and health in living pups. Throughout 2025, we released a series of video “pupdates” to share this progress openly.
The Pups Double in Size
By mid-year, all three pups had doubled their size compared to early measurements. This milestone reflects both their robust health and the accelerated growth rates we track against modern gray wolves. Watch the full update on YouTube.
Khaleesi Conquers the Pool
In another behavioral highlight, Khaleesi explored a pool environment for the first time. Playful exploration like this helps us observe developmental confidence, curiosity, and motor skills — all while providing enrichment. Watch the full update on YouTube.
Khaleesi Meets Her Brothers
Khaleesi, the female pup, was carefully introduced to her brothers Romulus and Remus. This update captures the first moments of pack bonding and gives insight into how we are monitoring social behavior and welfare. Watch the full update on YouTube.
Science, Ethics, and What’s Ahead
Genetics: Derived from ancient dire wolf DNA from a 13,000-year-old tooth and a 72,000-year-old skull, the dire wolf pups share close resemblance and significant genetic similarity to the dire wolves of the past.
Animal Welfare: The pups live in a secure expansive ecological preserve designed for health and safety, with monitoring for both physical and psychological well-being.
Transparency: Colossal’s de-extinction efforts adhere to international conservation principles. At this stage, the focus remains on scientific validation, ethical stewardship, and technology development within controlled environments.
Conservation Impact: The same technologies that created the dire wolves directly benefit endangered species. We’ve successfully cloned a litter of Red “Ghost” Wolves, producing four healthy pups that could help bolster recovery efforts for this critically endangered canid.
Making Extinction a Thing of the Past
For Colossal, 2025 has been a landmark year. The dire wolves have grown from newborns into recognizable canids with unique traits, while our dodo initiative has moved from concept to a clear genetic pathway. Both milestones reflect our central mission: to use biotechnology not only to bring back the past, but to provide new tools for conservation today.
The process of generating an organism that both resembles and is genetically similar to an extinct species by resurrecting its lost lineage of core genes, engineering natural resistances, and enhancing adaptability that will allow it to thrive in today’s environment of climate change, dwindling resources, disease and human interference — this is functional de-extinction in action.
Stay tuned for the next wave of pupdates and progress reports. The science is still unfolding — and we’re committed to sharing that journey every step of the way.
