We Can Resurrect Extinct Species… But SHOULD WE?

Summary

This episode explores the concept of de-extinction, focusing on efforts like Siberia’s Pleistocene Park and the possibility of bringing back species like the woolly mammoth. While cloning and genetic editing might recreate ancient creatures using DNA from close relatives, the challenges include incomplete DNA, ethical concerns, and the need for a suitable habitat. The episode also highlights how similar genetic tools can help save endangered species today, such as the California condor and black-footed ferret, by increasing their genetic diversity. Sponsored by 23andMe, it also touches on personal genetic insights provided by the company.

Takeaways

• 🌍 Pleistocene Park in Siberia aims to recreate an Ice Age landscape by replacing forests with grasslands and reintroducing large mammals like horses and bison.
• 🐘 Scientists are exploring de-extinction, potentially bringing back species like the woolly mammoth by editing the DNA of close relatives, such as the Asian elephant.
• 🧬 De-extinction is challenging because DNA deteriorates quickly after death, making it hard to obtain a complete genome necessary for cloning.
• ❄️ Mammoths, though preserved in ice, still have incomplete genetic material, requiring scientists to get creative by using gene-editing techniques.
• 🐔 Reverse engineering modern animals, like chickens, can potentially revive ancient species by modifying their genetic features, such as turning a beak into a snout.
• 🤔 Ethical considerations arise: would genetically engineered animals be true representations of extinct species, or just imitations?
• 💸 De-extinction is expensive and complicated, raising the question of whether the focus should be on saving species currently endangered rather than resurrecting extinct ones.
• 🌱 Reviving extinct species could pose ecological challenges, as their ancient habitats have changed, and their food sources or necessary microbes may no longer exist.
• 🦢 The same technology could be used to enhance genetic diversity in endangered species like the California condor or black-footed ferret to prevent future extinctions.
• 🔬 23andMe, a sponsor of the episode, helps people explore their genetic ancestry and learn about their DNA, which can influence traits like earwax type and caffeine tolerance.

Q & A

What is Pleistocene Park and what are its goals?

Pleistocene Park is a project located in Siberia, within the Arctic Circle. Its goal is to restore the landscape to what it looked like 2 million years ago by converting forests into grasslands and populating the area with large mammals, such as horses and bison, to mimic the ecosystem of the last Ice Age.

Why are mammoths considered important to the authenticity of Pleistocene Park?

Mammoths are considered important because they were a key species during the Ice Age, and their presence would complete the park’s goal of recreating an ancient ecosystem. Although large mammals like bison and horses have been reintroduced, mammoths would bring the landscape closer to what it once was.

How did the last known mammoth die, and when?

The last known mammoth died about 4,500 years ago on an island in the Arctic Ocean. Its extinction marked the end of the species.

What is de-extinction, and how does it work?

De-extinction refers to the process of bringing extinct species back to life. Scientists try to reconstruct an organism by using its DNA, either through cloning or gene editing. In cloning, a complete set of DNA instructions is inserted into an embryo. However, in the case of extinct species, the available DNA is often incomplete, so scientists use methods like gene editing to recreate the missing genetic components.

Why is cloning a mammoth not as easy as it may seem?

Cloning a mammoth is challenging because the DNA available from preserved mammoth remains is incomplete. A complete set of genetic instructions is needed to clone an organism. Over time, DNA degrades, making it difficult to gather all the necessary genetic information to recreate a mammoth.

What alternative approach do scientists suggest for recreating mammoths?

Instead of cloning a mammoth directly, scientists suggest using gene editing to modify the DNA of a close relative, such as the Asian elephant. By replacing certain genes that give mammoths their distinctive traits—like cold resistance, large tusks, and fur—with those of an Asian elephant, they could create a hybrid that closely resembles a mammoth.

What are some of the challenges in using elephants for mammoth de-extinction?

One challenge is the long gestation period of elephants, which lasts more than a year and a half. Additionally, Asian elephants are already endangered, so using them for de-extinction efforts could put them at further risk. Moreover, the process would need to produce hundreds or thousands of hybrids to establish a genetically diverse population, which presents a significant challenge.

How does the idea of reverse engineering chickens relate to de-extinction?

Scientists have found that chickens are distant relatives of the T. rex, and by controlling certain genes, they can express more dinosaur-like features in chickens, such as turning the beak into a snout. This method of gene editing could be applied to other species, like elephants, to create hybrids that resemble extinct animals like the mammoth.

What ethical concerns are raised about de-extinction?

Ethical concerns about de-extinction include whether it is worth reviving species that no longer have a natural habitat or ecological role. Additionally, the process is expensive and complex, and there are concerns about the unintended consequences of introducing de-extinct species into modern ecosystems. Some argue that the focus should be on preventing current species from going extinct rather than bringing back those already lost.

How could genetic tools used in de-extinction help endangered species today?

The same genetic tools used in de-extinction could be applied to endangered species to increase genetic diversity within their populations. For example, species like the California condor or the black-footed ferret, which are on the verge of extinction, could benefit from genetic editing to strengthen their populations, making them more resilient to disease and other threats.