Reviving Extinct Species: Scientific Aspirations and Challenges
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The Fascination with Extinct Species
Throughout history, humanity has been captivated by the notion of extinct animals. Long before we mastered the intricacies of genetics, we uncovered their fossils, envisioned their appearances, and imagined their return to existence.
The allure often brings to mind Michael Crichton's renowned novel, Jurassic Park, which has inspired a franchise of blockbuster films. The concept of resurrecting dinosaurs is thrilling—yet, as depicted in the movies, it rarely ends well.
Even prior to Jurassic Park, the idea of encountering ancient species was popularized. Jules Verne's 1871 work, Journey to the Center of the Earth, portrays explorers who stumble upon living descendants of prehistoric creatures hidden in deep caverns.
However, the fascination with resurrecting extinct species isn't merely confined to fiction. Various organizations, such as Colossal Biosciences, are actively pursuing the scientific revival of species like the woolly mammoth and thylacine. But what drives this ambition? Is it mere human arrogance, or could there be genuine advantages?
The Science Behind Species Revival
To understand the process of reviving extinct species, we must first recognize that Jurassic Park presents a simplified, and often incorrect, view of genetics. The initial step involves acquiring the DNA of the extinct species. Colossal Biosciences is focused on the woolly mammoth and thylacine, both of which went extinct relatively recently in evolutionary terms. Woolly mammoths vanished roughly 10,500 years ago, while the last thylacine died in captivity in 1936.
DNA has a half-life of approximately 521 years, meaning that after five centuries, half of the DNA will have degraded, rendering it unreadable. This degradation is exponential; after a millennium, only about 25% remains intact, and after 4,000 years, a mere 0.02% is left. Therefore, viable DNA from species that went extinct millions of years ago is virtually nonexistent.
Once DNA is obtained, it's insufficient to simply create a woolly mammoth in a lab. A close living relative is essential to provide a foundation for genetic modifications. Colossal plans to use an African elephant as the surrogate for their gene-edited woolly mammoth embryo since it is less endangered than its Asian counterpart and larger in size.
Benefits of Resurrecting Woolly Mammoths
Colossal Biosciences asserts that their goal extends beyond displaying resurrected woolly mammoths for public viewing. They cite two primary motivations: re-establishing tundra ecosystems to enhance carbon absorption and validating the extinct species revival concept.
The first goal presents a compelling narrative: “We are saving the planet!” Woolly mammoths could help restore grasslands, which are more effective at sequestering carbon and mitigating climate change. However, the actual impact of this endeavor remains untested in larger environments, and it’s uncertain how many mammoths would be necessary for a significant effect.
The second objective, proof of concept, is equally significant. Other species that could be revived include:
- Passenger pigeons
- Dodo birds
- Elephant birds
- Moas
- Eastern cougars
This research could also lead to advancements in genetic engineering, potentially paving the way for future interventions in human genetics.
The Complex Process of Resurrection
Successfully reviving an extinct species requires several critical components:
- Sufficient preserved DNA to identify unique mutations.
- A closely related species to provide eggs and sperm.
- Custom-designed CRISPR interventions for the necessary mutations.
- Live females from the related species to serve as surrogate mothers.
Each of these steps is intricate and time-consuming. Colossal has identified over 50 mutations needed to restore the woolly mammoth's cold resistance. Achieving all these mutations in a single egg cell is a monumental task.
The path to resurrecting a species is fraught with challenges and potential setbacks. For example, if 49 mutations are successfully edited, but the 50th introduces complications, the entire process must restart.
The Future of Extinct Species Revival
As we await the outcomes of Colossal's endeavors, the question remains: can extinct species truly be brought back?
The first video, "Why Resurrecting Extinct Animals Is Actually A GREAT Idea," discusses the potential benefits of bringing back extinct species.
The second video, "Should We Bring Back EXTINCT ANIMALS? (Pros and Cons)," explores the various arguments for and against the revival of extinct species.
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