Science, Art, Litt, Science based Art & Science Communication

Is de-extinction a good idea?

Q: Is using genetic engineering to bring extinct species back a good idea?

Krihsna: Some think it is a good idea and some are aginst it! Now let us consider all the pros and cons of de-extinction.

The concept of de-extinction—bringing extinct animals back to life through genetic engineering—is beginning to move from the realm of science fiction to reality. Now, a new analysis of the economics suggests that our limited conservation funding would be better spent elsewhere.

De-extinction is very much a science in development, but it’s moving at a rapid pace. The first milestone was in 2003 when European scientists resurrected the Pyrenean ibex, a type of mountain goat that had gone extinct a few years earlier.

Sadly, the kid died a few minutes after she was born, so the poor ibex was not just the first animal to be brought back from extinction, but also the first to go extinct twice. Since then, scientists have been refining their methods and developing new de-extinction techniques (2).

In Australia, Prof Michael Archer and colleagues are working on bringing back the gastric-brooding frog, a remarkable animal that nurtured its young in its stomach before burping up fully-formed froglets. So far, the team has produced embryos that ‘almost’ turn into tadpoles but not quite. The next step is to persuade these embryos to turn into frogs (2).

Can the resurrected be the same as the ones that got extinct? No, they can never be exactly the same. For instance let us consider the wooly mammoth. When the scientists are done, they will have created not a true mammoth, but an elephant with a sprinkling of judiciously placed mammoth DNA. It will have long, shaggy fur, thick rolls of insulating body fat, and haemoglobin that can ferry oxygen around the body at sub-zero temperatures.This will be an animal that looks like a mammoth, but is really an elephant whose DNA has been altered so it can live in the cold. You could call it a ‘mammophant’ if you like, or an ‘elemoth’.(2)

Added to that, we now realise that all animals are a product of their DNA and of the environment in which they live, along with the interaction between the two. Created in a lab, nurtured in the womb of a modern elephant, and raised in a world that has changed radically since mammoths went extinct thousands of years ago, the experiences of this new-age pachyderm will be different to those of its Ice Age doppelganger… all of which will conspire to make it less similar to the original woolly mammoth.

But does this matter? Many will argue that, if the de-extinct animal looks and acts like its predecessor, then that’s good enough.

In America, scientists are working on bringing back the passenger pigeon, a rosy-breasted bullet of a bird that once flocked in the billions; and the heath hen, a stumpy avian wallflower that lived in the scrubby plains of New England.

In the UK, researchers are considering whether or not to bring back the so-called ‘Penguin of the North’, the great auk.

Meanwhile, in South Africa, they’re trying to revive the quagga, a bizarre zebra-like creature with a stripeless behind! In South Korea, Japan and the US, three separate teams are racing to bring back that most iconic of Ice Age beasts, the woolly mammoth.

It also depends on the species. Some projects use ‘back-breeding’. Quaggas, for example, are related to living zebras. So scientists are choosing the zebras that look most like quaggas and letting them breed. The aim, over successive generations, is to create animals that look like quaggas.

Other projects, however, involve assisted reproduction and some rather elegant genetics.

Some are using cloning; others, stem cell science. For example, Prof George Church at Harvard Medical School aims to create a mammoth by ‘editing’ mammoth genes into elephant cells.(2)

The Woolly Mammoth

Different people might have different 'opinions' on this aspect. Yes, we can test our abilities. However, this costs us a lot.

To estimate how much it would cost to sustain a population of de-extincted animals, researchers used databases from New South Wales, Australia, and New Zealand that methodically track the cost of conserving endangered, but still living, species. This allowed the scientists to extrapolate the cost of preserving resurrected animals that are similar to living analogs. The cost of caring for a population of resurrected mammoths, for instance, should be similar to the cost of caring for the endangered Asian elephant. The approach completely ignores the large up-front cost of developing and using the genetic and biological technologies to actually resurrect the species. So it underestimates the actual cost of de-extinction programs, the authors say (1). Even so, the results look grim.

The team considered two different scenarios: one in which the government assumes responsibility for the conservation of resurrected species, and another where private companies sponsor the project. In the first scenario, the money needed to maintain the population of resurrected animals comes directly out of the government's conservation budget, meaning all existing conservation efforts lose some funding. The result, the team calculates, would be an overall loss of biodiversity—roughly two species would go extinct for every one that could be revived.

In the second scenario, where the costs are absorbed by private interests and don't detract from the already limited conservation budget, the researchers calculate that we could see a small uptick in biodiversity, especially for animals for which the necessary conservation tools and techniques are already being used to conserve existing endangered species. Reviving the Forbes' snipe (Coenocorypha chathamica), a long-billed bird native to New Zealand that went extinct sometime around the 19th century, for example, would create a net biodiversity gain in New Zealand because many of the conservation practices needed by the snipe are already being carried out for other species living on its former habitat of Chatham Island.

However, the results also show that if instead of focusing the money on de-extinction, one allocated it into existing conservation programs for living species, we would see a much bigger increase in biodiversity—roughly two to eight times more species saved. In other words, the money would be better spent elsewhere to prevent existing speci..., the team reports today in Nature Ecology and Evolution.

The same techniques being developed to help resurrect extinct species can also be used to help save living species on the brink of extinction.

Mammoths, Tasmanian tigers and even Elvis could soon be brought back from the dead, thanks to intriguing advances in cloning and gene editing. But would they be the real thing?

Then the Q arises: There are limitations on which species can undergo de-extinction. First up, scientists need to have a source of the animal’s DNA.

Sometimes this comes from preserved museum specimens or from cells that have been collected from live animals and frozen away. Sometimes it can come from fossils.

But DNA disintegrates over time, meaning that after a couple of million years there is simply no DNA left. Dinosaurs famously went extinct 65 million years ago, so their DNA is lost forever. No DNA, no dinosaurs.

There are lots of good reasons to bring back extinct animals. All animals perform important roles in the ecosystems they live in, so when lost species are returned, so too are the ‘jobs’ they once performed.

Woolly mammoths, for example, were gardeners. They knocked down saplings, ate grass and fertilised the ground via their nutrient-rich dung.

Studies suggest that if large grazers were returned to the far north, biodiversity would increase again.

It could be the same for other de-extinct animals, too.

De-extinction provides a means to enhance biodiversity and help restore the health of ailing ecosystems. It could be a conservation tool, and by choosing to bring back animals that are genetically unique.

Then there are the benefits that humans could glean. The gastric-brooding frog somehow converted its stomach into a makeshift womb. It stopped producing stomach acid so it didn’t digest its young. If scientists could figure out the changes involved in this, it could lead to treatments for stomach ulcers or could help people recovering from stomach surgery.

Every day, between 30 and 150 species disappear from the face of our planet, and studies reveal that extinction rates today are 1,000 times higher than they were during pre-human times.

We live in a time of mass extinction, and de-extinction has been proposed as a key way to undo some of that harm. To reverse extinction would undoubtedly be a huge moment for the fields of biology and conservation, and a feat that could motivate future generations of scientists and wildlife defenders.

Some people are against de-extinction because they say it feels unnatural. They are wary of genetic modification and accuse scientists of playing God. But proponents argue that the techniques being developed to make de-extinction happen all have natural counterparts in the wild.

Just as IVF has become an accepted medical technique, so de-extinction researchers hope that concerns about their experiments will fade once the science has proved its worth.

Critics also claim that de-extinction is stealing funds and attention from traditional conservation efforts.

Now you can decide for yourself whether de-extinction is a good idea or not!

Footnotes:

1. https://www.science.org/content/article/bringing-extinct-species-ba...

2. https://www.sciencefocus.com/nature/de-extinction-can-we-bring-exti...

0 members like this