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Resurrection Biology Part 2: On Mammoth Steak and Coral Reefs.

January 26, 2014 Leave a comment

It seems there is a larger conversation to be had about the notion of resurrection biology. A friend of mine and I had that conversation after I posted up my last blog post. I thought it was that fun that I would do a follow up post on my thoughts regarding two issues he raised in that conversation: resurrection biology for food production and ecological services.

Food Production

The whole reason for this section is this comment:

Another potential use of resurrection biology which I think most people would object to is farming; imagine mammoth farms, admittedly their natural behaviour wouldn’t be as great, their habitats altered, but considering how many farm animals have been altered and placed into habitats we have designed it does seem a viable option for extinct edible megafauna. – Washington Irving

I don’t think I need to tell you that the human population is growing, I hope it’s also self-evident that the population increase has sped up over time. To demonstrate, the time it took to go from 1 billion to 2 billion was 123 years (according to United States Census Bureau (USCB) data) while the time from 6 to 7 billion was 12 years (again, USCB data) and it’s estimated we’ll pass 8 billion by another 16 years (you guessed it, USCB data). This last one actually surprised me but it seems that we’re living in an age in which, due to an ageing population and an increased life expectancy for children and infants, the rate of growth is finally sloping off. All these extra people need a place to live and food to eat so, maybe if we resurrected extinct species they’ll provide the food we’ll need?

I would be inclined to think not and here’s why: First off, you have to actually make a population of organisms from scratch, which is no small task, take a look at conservation and reintroduction efforts across the globe and how much effort has been put into these programmes to see why this is difficult. Secondly, we would be producing food from an organism that, potentially, no human has eaten before so there would necessarily be testing required to see if this food is a healthy alternative to currently farmed species. This is closely related to another point, the fact that these foods would fall under the domain of Genetically Modified Food and here we open a hornet’s nest of political debate on the nature and safety of GM food which I’m not going to wade into here, except to say that it would make some people hesitant to buy into the new food source.

The example species Wash gave for the possibility of farming extinct species was farming Mammoth for steaks. Unfortunately, this is a terrible example for the potential of resurrected farm animals. Mammoth are close relatives of Elephants and as such we can say with a level of certainty that they would be long lived, slow to grow and, what is called k selected which essentially just means that they have relatively small numbers of children, perhaps one at a time which are then cared for by parents or members of a group; the opposite is r selection which is where many offspring are born all at once and are typically abandoned to fend for themselves.

Source: http://sprudge.com/saturday-sept-th-san-francisco-huge-block-party-with-coffee-bar-sf-and-scout-mob-plus-ribs.html

Unfortunately, this might not be feasible.

What this means is that it might take a decade to grow the initial population of mammoth to adulthood and then you’d need to leave many of them alive to produce the next population. Mammoths would also require huge tracks of land to maintain their population with tonnes and tonnes of grass every day. So there are quite a few problems I can see, my final problem is that the economic costs are really quite high given the genetic meddling needed, the set up of the population et c. but are there any cases which would be suitable for resurrection farming.

Now to raise a point I didn’t realise until I started typing up this post which is the fact that we don’t even need to resurrect extinct megafauna to farm, we could equally easily resurrect extinct plants, or fungi, or yeast or any living thing which we have records of their genetic material (Mesozoic organisms are apparently too old for this, sorry Jurassic Park). It’s possible we could develop an extinct species with higher yields than current farmed species, or with different nutritional benefits. It seems to me that the possibilities here are basically the same as with the genetically modified crops which we are already developing and that extinct species won’t really add anything to their potential.

There is one example that I’d mention for it’s possibilities, which is the Gros Michel, this is a banana variety which was used until the 1950’s when it was devastated by a fungal infection which spread extremely rapidly due to the low genetic diversity of the variety. Everyone switched to the Cavendish cultivar and now the only legacy left is the banana flavouring which is still the same as when it was developed to taste like the Gros Michel. The possibility of bringing back species or cultivars devastated by diseases gives hope to the extremely homogenous cultivars used today, because were they wiped out, it might be possible to resurrect them based on this technology.

Source: http://tangerinetravels.blogspot.co.uk/2011/02/am-reading-banana-fate-of-fruit-that.html

Spot the difference.

Ecological services

The other half of our conversation was on the potential to help with problems caused by extinctions, such as the destruction of species which provide what are called ecological services. Ecological services are basically things which species naturally do, which benefit human society, the canonical example being bees pollinating flowers of crops but there are other, more subtle ecological benefits such as the protection forests provide against flooding.

So what if there are species which used to exist which was better at providing some ecological services than current ones, perhaps there is an extinct species of tree with roots particularly adept at drawing up the water during floods but does not dry out the soil too much when water isn’t quite so abundant. Conditions on this planet has varied so much that it’s entirely possible such species have existed.

The difficulty I see with this plan is that you first need to resurrect the species and then see how it would interact with an ecosystem before introducing it. This would mirror the process already used to determine if biological control agents introduced into new environments would potentially become invasive and harm the ecosystem more than it would help. So given the added cost of trying to create a viable population, nearly, from scratch you then have to make sure you’ve not resurrected a species which is going to oust other members of the ecosystem you intended to fix.

Source: http://www.bioimages.org.uk/html/p7/p71469.php

Imagine the Harlequin Ladybird was extinct and we thought we’d reintroduce it to control aphid populations.

The final point I think which would probably be raised first by others, again it is quite Jurassic Park: The species went extinct for a reason, maybe it should have stayed that way. While I don’t personally believe in a grand plan for evolution, I could modify this argument to the notion that the environmental changes which caused the species’ extinction in the first place could still be in effect and so the species would be doomed to extinction all over again. This would be my response to my friends comment:

I think it depends also how you would re-introduce extinct species, as some are able to readjust to natural settings after human interaction. I’m thinking more along the lines of coral reef communities where some species will go extinct and if these can be resurrected it’d be extremely useful, even if it is in potential new habitats due to warmer oceans… – Washington Irving

It’s possible we could reintroduce species such as those coral reefs which Washington mentions but the result could be another extinction all over again. Even if we got everything right, we cannot be sure that the species would provide the ecological services we want and that they would not be destroyed by some process, whether artificial or natural.

In the end, the only use I can see for resurrection biology is for the purpose of maintaining species which already exist as Washington says:

I’ve wondered at times how species could be integrated into existing areas, and the only result I see is that the competition negatively effects the previous community. […] I still think that resurrection biology would have a potential use primarily for helping current species with low populations and natural behaviours which are known be able to recover or even to try and mitigate losses from global warming and ocean acidification events. – Washington Irving

If we can maintain the species which are at risk today, that is the best outcome for resurrection biology. We aren’t here to fix the world, the world isn’t broken, the problem is that it may become just a little less interesting if we allow processes currently shaping our world to continue along their path.