Can Genetic Engineering Bring Back Extinct Animals?

http://news.nationalgeographic.com/2015/09/150920-book-talk-simon-worrall-genetic-engineering-passenger-pigeon-resurrection-science-neanderthals/

by sethbannon • 11 years ago

44 28 11 years ago

news.nationalgeographic.com

tristanj• 11 years ago

Genetic engineering can't bring back most extinct animals. DNA molecules have a half life of around ~500 years and samples older than a few hundred thousand years will have too many errors to recreate. Better statistical techniques will push this bound but it's hard to argue against physics. It's estimated that DNA older than 20 million years old will be fully unrecoverable.

Notice how all the author's examples are recently extinct species, not ancient ones. I guess they don't mention this because it doesn't fit with their worldview.

Some sources:

http://www.the-scientist.com/?articles.view/articleNo/32799/...

https://en.wikipedia.org/wiki/Ancient_DNA

giarc• 11 years ago

Could you not produce viable samples by collecting multiple copies of the DNA and overlapping them, thus removing the errors that would likely happen at random locations?

noir_lord• 11 years ago

Better statistical techniques will push this bound

That's what he meant by statistical techniques, we don't currently read a full "stream" even with brand new DNA, we smash it to bits then read those and have the computers put them back together.

At a certain point though what's left is too garbled or in too small sequences so that there isn't enough overlap that you can't put humpty back together again :).

searine• 11 years ago

Not likely. Dude to the chemistry of nucleotides, they can degrade in a particular pattern that obscures the ancestral allele. For example the deamination of cytosine to thymine can leave us with an ambiguity in what in our read for the correct nucleotide is.

Was it thymine? Or was it cytosine that degraded to thymine? That means for literally 50% of the genome we have a huge ambiguity and few ways to tell what it really is.

We can use the ancestral allele from a nearby extant species, but then we miss out on all the extinct variation (which is the important stuff).

We can try to increase coverage of the ancient genome to capture loci where cytosines haven't deaminated, but thats tough for a dozen reasons, and in the end you'll still have no confidence in 25% of the genome.

We can get very close to a full ancient genome, but never 100%. Maybe through transgenics, selective breeding, and ancient sequencing we can re-create ancient species, but we will never make them exactly as they once were.

mehwoot• 11 years ago

Yes, but with a half life of 500 years, the amount of information you have halves every 500 years you go back. At some point there just isn't enough information to go viably go back further.

cpeterso3• 11 years ago

Has there been much work on cloning endangered species? I guess resurrecting extinct species would be "cooler", but helping endangered species would be less controversial.

Frqy3• 11 years ago

Apart from very close species (like incubating passenger pigeon DNA in a fantail pigeon host), is it possible to recreate say a woolly mammoth even assuming you can perfectly reconstruct the DNA itself?

That is, how much of an organism is encoded in the DNA and how much in the mother's body? And yes, this question is derived from GEB[0].

[0] https://en.wikipedia.org/wiki/G%C3%B6del,_Escher,_Bach

271828182842• 11 years ago

Out of curiosity, does anyone know anyone else in real life that is not open to the idea of bringing back some extinct species?

I noticed this recently. Not a single person in my social network is against the idea of trying to clone a mammoth or trying to clone an extinct cat or dinosaur. There is some hesitancy when you bring up possibly reviving old bacteria, but that's it that I've noticed.

timClicks• 11 years ago

There is a little bit of a safety concern with some of the larger species of New Zealand moa. They're massive and New Zealanders currently don't really have anything that can harm them in the bush (e.g. no big cats, bears, snakes).

One of the proponents of the project (http://bringbackmoa.org/) has stated that he's not interested at de-extinction of the larger species (http://www.stuff.co.nz/national/10216641/Time-to-bring-back-...).

macspoofing• 11 years ago

Not a single person in my social network is against the idea of trying to clone a mammoth or trying to clone an extinct cat or dinosaur.

What are you going to do with them? Neither a T-Rex nor a Mammoth would do well in the wild and even if you put the issues of environmental difference between the distant past and today, you may be disrupting existing large fauna, which is already on the brink of extinction due to human activity. If that's not the case, you'll be left with the ethics of zoos and animal rights.

271828182842• 11 years ago

If that's not the case, you'll be left with the ethics of zoos and animal rights.

This is kind of to my point. Nobody I know has raised objects like that, and animal rights is largely PR based anyway. (E.g., politicians eating baby elephant but social media upset about Cecil.)

Nobody I've talked to has said something like, "We shouldn't do it for ethical reasons and they are..." which I find interesting and why I broached the topic.

eruditely• 11 years ago

Keep them in large cages and let us look at them.

asciimo• 11 years ago

Myself. It's interesting that so many people take it for granted that resurrecting extinct animals is a "good thing." Why is it a good thing? The referenced article doesn't ask this question.

Ben Novak (the Passenger Pigeon researcher) said in an interview "... the destructive force of the flocks led to a radical rejuvenation of forests. Thick layers of pigeon droppings fertilized the soil, which soon led to new growth." Is new forest growth currently an issue? Are Passenger Pigeon droppings the only solution?

http://www.spiegel.de/international/zeitgeist/scientists-aim...

sehugg• 11 years ago

One could also ask the question of whether humans need to behave in such a way as to bring about the extinction of so many species. Certainly the passenger pigeon wasn't made extinct for the common good.

Biodiversity is the only answer we have right now to the question of how to maintain a healthy planet (https://en.wikipedia.org/wiki/Biodiversity#Services_enhanced...). Until we get a lot smarter, it's wise to learn how to better preserve as much as we can.

cpeterso3• 11 years ago

How would you feel about cloning endangered species compared to resurrecting extinct species? Endangered species are still part of ecosystem, so you avoid some of the problems or arguments around introducing new, invasive species.

guard-of-terra• 11 years ago

Siberian landscapes suffer much from not having mammoths, sabertooth tigers and wooly rhinos. Half of Siberia could be productive arctic steppe instead of grim forest we see today (we don't because there's no business being there).

See https://en.wikipedia.org/wiki/Pleistocene_Park

6502nerdface• 11 years ago

I think I agree with you that on balance it's not an obviously wise thing to do. But for fun, I tried to think of some arguments in favor of resurrecting extinct species:

- (Karma) Humans have been the proximate cause of so many extinctions, and this is a chance to "undo" some of that harm.

- (Glory) Life seeks life. What could be more glorious and good than to finally apply the knowledge and art so painfully accumulated by the the hundred suffering generations before us to a real conquest of death?

- (Knowledge) Merely by attempting to resurrect an extinct species, we would learn so much. And if we ever succeeded, it's likely that the things we could learn by observing extinct phenotypes and extinct phenotype-genotype mappings would make for a true revolution in the life sciences.

blisterpeanuts2• 11 years ago

(Biology) restores some bio-diversity to the planet.

(Cuisine) If passenger pigeons became commonplace again, we could eat them.

Regarding your point about knowledge: totally agree. If we could coax extinct life forms back into existence, think of the likely medical implications. Regenerating limbs, repairing brain damage, curing MS and ALS and a host of other genetic problems.

People like this science writer keep saying "We might be able to, but should we?"

Of course we should. The opportunity costs of not doing it are potentially enormous.

kbenson• 11 years ago

I agree with the latter reason, but for Karma, arguments such as that always strike me as odd. It's sort of like admitting that your unwittingly blundering in and making a hash of other people's relationships has caused you to try to try to purposefully insert yourself into more relationships in the future to try to help. Perhaps the lesson being missed there is that you shouldn't intrude in those relationships at all.

Glory? Eh, if it's beneficial overall, I don't see too much harm, but it doesn't sway me much.

Knowledge is the real inventive here for me. Knowledge is how we advance our species as a whole. It's the only thing that makes this discussion possible, on every conceivable level.

Dylan16807• 11 years ago

Well there's not a huge variety of species we can actually bring back. DNA doesn't last all that long. So nobody has to worry about the implications of dinosaurs. All-in-all it's a pretty minor thing.

michaelpinto• 11 years ago

It could be argued that our limited resources should go into preventing existing species from going extinct (and saving their ecosystems) rather than bringing back ones that are gone. And given the crisis situation we're in it's not an academic question:

http://www.washingtonpost.com/news/morning-mix/wp/2015/06/22...

cpeterso3• 11 years ago

Stewart Brand and the Long Now Foundation have a deextinction research program called Revive & Restore:

http://longnow.org/revive/

BurningFrog• 11 years ago

Bringing back extinct species isn't cool. You know what's cool?

Designing brand new species in DNA!

ams6110• 11 years ago

Changes are now happening so quickly that they appear to be driving some species towards extinction because they can’t adapt fast enough.

Well, yeah -- that's how natural selection works.

vdutta• 11 years ago

It's a well known fact that most ecosystems are very delicately balanced. Introducing new species can often have devastating effects on existing ones. So even if we did resurrect extinct species, they may have to remain domesticated, as our toys.

Can Genetic Engineering Bring Back Extinct Animals?

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