Can we undo the eco-damage we’ve been doing, as a species?

I lament the way that humans have trampled through the Earth’s fragile environment. We’ve already destroyed a lot of habitats, and with it a dismaying number of species. You can be sure we’ll destroy a lot more before we fall into extinction ourselves, which is where we’re obviously heading if we carry on as we are.

Podocarp forest near Puketitiri, inland Hawke's Bay, New Zealand
Podocarp forest near Puketitiri, inland Hawke’s Bay, New Zealand.

Many of those extinctions have happened just in the last few decades, but the human impact on nature has been traced back to Pliestocene times. For a long time there was debate: was the repeated destruction of Pliestocene megafauna, straight after humans arrived, a coincidence? Due to other factors? What? The jury is still out to some extent – there were probably multiple factors. But there’s no question that humans were one of them – and a very large part of the calculation.

The last of those collisions, incidentally, occurred in the last millennium when New Zealand was reached by humans for the first time. Until the late thirteenth century, New Zealand carried its ancient biota – a literal ‘lost world’ with its Mesozoic-era forests, ferns, giant birds and no mammals other than bats, untouched by humans. Within a short period of human arrival, much of it had gone – repeating the same pattern evident in Europe, Asia, Australia and the Americas.

Can this be undone? Technology offers ways, largely through genetic engineering, although inevitably – human nature being what it is – that work  will likely cause problems. There’s a project on to reverse-engineer theropod dinosaurs out of chickens. It’s not hard. Birds didn’t evolve from dinosaurs – they are dinosaurs, and they still have the genes of their jawed and tailed Mesozoic cousins. We have but to switch them on, and birds will grow theropod-style leg bones, tails, and toothed jaws. Already gene-tinkering has produced chicken embryos with dino legs and others with dino-jaws.

Reconstruction of Troodon by Iain James Reed. Via Wikipedia, Creative Commons attribution share-alike 3.0 unported license.
Looks like a bird, except for the dino jaws, legs and tail. Reconstruction of Troodon, a Mesozoic-era maniraptor, and cousin to modern birds, by Iain James Reed. Via Wikipedia, Creative Commons attribution share-alike 3.0 unported license.

To my mind that sets to rest any debate about what birds are – but it’s not cool. We don’t know what consequences these changes will have. I’m not thinking of flocks of ravening dinochickens roaming suburban neighbourhoods and terrorising cats. Our knowledge of genes is incomplete, despite our conceits of being ‘advanced’ and ‘sophisticated’. It was only recently, for instance, that ‘junk’ DNA – stuff that didn’t have an obvious purpose – was found to have functionality after all. One nasty scenario is that we accidentally create an easier disease vector for strains of bird flu that we only discover after ChickenosaurusTM has become the new must-have status pet for households. It’s unlikely, but it wouldn’t be good to find out the hard way. The other issue is that, for all that genetic modification is declared ‘safe’, we don’t know the long-term consequences, or what happens when modified genes ‘leak’ into the wild.

The thing about gene engineering, though, is that it offers ways of recovering creatures lost to our own human nature. There’s a been talk of rebuilding the mammoth using CRISPR genetic splicing techniques and modern elephant cells, but it’s not actually possible. The issue is the quality of mammoth DNA. The stuff’s fragile, and being able to analyse the genome in preserved animals doesn’t mean the same material is viable as a building block for a life-specimen.

Male (bottom) and female (top) huia from W. L. Buller, 'A History of the Birds of New Zealand', 1888. Public domain.
Male (bottom) and female (top) huia from W. L. Buller, ‘A History of the Birds of New Zealand’, 1888. Public domain.

More recent extinctions offer no better potential. Here in New Zealand the obvious ‘recent loss’ is the huia. This wattlebird, a close relative of the kokako, ranged on the east coast of the North Island and was last seen at the end of 1907, when W. W. Smith observed three in the Tararua ranges north of Wellington. Other sightings since, one as late as the 1960s, have been unsubstantiated and the bird is considered extinct. There was a proposal in 1999 to clone huia from DNA in preserved specimens.  There were a fair number in public and private hands. (My great aunt used to have two – a male and female – which sat in their china cabinet. I don’t know what became of them.) However, once again, none were well enough preserved to provide DNA.

So is there hope? Yes, given the right circumstance. Think quagga (Equus quagga quagga). This zebra sub-species with its distinctive colouring and lack of hind-quarter stripes lived primarily in South Africa and was declared extinct in the wild in the late 1870s. The last known specimen died in Amsterdam Zoo in 1883. Again, preserved examples exist. And again, the DNA in them isn’t good enough. However, they were long considered a close sub-species of other zebra – not a separate species. This means its genes are in other zebra, so it’s possible to recover most of the quagga’s unique features – notably its colouration and stripe pattern – by selective breeding.

Reinhold Rau began doing just that in 1987 with the Quagga Project, though it’ll take a while to show full results. Although the species status of the quagga was still debated when that project began in the 1980s, a 2005 study showed that the quagga had diverged from the plains zebra only between 290,000 and 120,000 years ago. So yes, back-breeding is eventually going to produce a zebra that’s pretty much quagga-like.

This means we can undo at least one piece of the extinction-damage that humans seem to be so expert at creating.

Copyright © Matthew Wright 2017

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14 thoughts on “Can we undo the eco-damage we’ve been doing, as a species?

  1. Humans do not seem to me to actually be a native species to this planet. We do not fit into the scheme of Nature and we do nothing but destroy everything we touch. The dinosaurs succumbed to an act of Nature, but we are causing our own destruction. IMO

    1. I think we are definitely destroying ourselves. And we’ve always been self-destructive. It was probably a survival technique, way back when – smash everything except what we define as ‘us’, and so stay alive. If the environment’s ruined, move to another one. Except now we dominate the planet and there isn’t another environment to move to. Damn. It’s been staring us in the face a while – Einstein pointed it out in the late 1940s when he explained that nuclear weapons changed everything…except the way we think. And I think that’s true of a lot of what we’ve invented, build and consume, especially on the scale we’re doing it at.

    1. I suspect it’s already happening, when you look at how many species of bacteria are turning up antibiotic resistant, these days. They were around long before us… and they won’t get dented by our puny efforts to control them.

  2. I’m of the opinion that we should do what we can to bring back species that are extinct because of humans, but we shouldn’t bring back species that went extinct before us. Huia are a great example.

    Fascinating that your great aunt had a pair of huia specimens! My great great grandfather used to keep them as pets. Such beautiful birds and a real shame that they are all gone. Their extinction came as a real surprise to many. I guess that we should just be thankful that other birds such as the kakapo were saved from the same fate.

    1. Yes – DOC has done a wonderful job pulling various species back from the brink. (A ‘collecting hat’ they used for the insemination programme is on display in Te Papa.) It’s always possible that the huia are still around – after all, the takahe was thought extinct. Hopefully there is a breeding population out there somewhere, deep in the Urewera maybe, or the Tararuas? On that note, incidentally, it’s been great in recent years to get tui returning to urban areas – a real recovery.

      The one that still intrigues me is the moa: Fijordland’s always been the suspect refugium for them, and just a few years ago there was talk of lost moa in back-country Hawke’s Bay. Personally I doubt that any are left – there would have to be a breeding population of dozens, at least, for them to survive; and the combination of their physical size and the fact that we pretty much poke into every corner of even Fijordland these days suggests we’d have found them by now, if there were any to find.

      1. The re-discovery of the Takahe is fascinating, not least because it isn’t like they are small brown birds that might easily be missed – they are like walking traffic lights. Incredible that they were thought lost and then found again!

        I’d love to believe that there are a small population of huia waiting to be discovered, how incredible that would be. Sadly I don’t hold out much hope though. The South Island kokako is a different matter.

        My Gramps may have been one of the last people alive to have seen a laughing owl. He was fairly certain that’s what it was. That’s another species I wish we still had.

        When it comes to moa I’m extremely skeptical. The people who go looking for them tend to be international cryptozoologists looking for something to do between their searches for yetis and the Mongolian death worm, and they seldom have any knowledge of the NZ bush or wildlife. It is a romantic thought, but sadly I suspect that if there was a remnant population of moa then there would have been evidence found by now. Would love to be proven wrong though!

        1. Yeah, me too. It would be fantastic if some were found! But like you I’m deeply sceptical. I did write about that possibility in that sci-fi history book I wrote a few years back for Penguin – in one ‘alternative history’ scenario, I postulated that some had survived into the nineteenth century. But they still went extinct, this time at the hands of colonial-era chefs. Moa had a small problem, you see. They were delicious…

  3. I don’t see much point in bringing back extinct species, even recent ones, when we can’t seem to stop driving existing species toward extinction by habitat destruction. I think there will always be a multitude of life forms on the planet, but many current ones will vanish before we (finally) go extinct ourselves.

    1. I’ve heard that we’re in the middle of a great extinction right now – species are vanishing faster than ever before, possibly faster than many of the uncatalogued ones can be identified. I fully expect humans to follow suit, and likely fairly quickly if we carry on the way we are going. Pessimistic, I know, but – well, probably realistic. All we have to do is break the environment, fight over what’s left, and fight with each other anyway because humanity’s always done that, and we’ll knock our civilisation over soon enough. How long a residual cave-dwelling population will last is moot – all humanity was virtually knocked over in the last big glaciation. As I understand the genetic studies, H. sapiens survived by the merest whisker – reduced about 70,000 years ago to a tiny, tiny population, which is why we’re unusually genetically close, as species go, today. It seems intelligence isn’t a survival advantage after all… which is a pity, because it COULD be, if we wanted – as a species, all working together to help uplift each other.

  4. There is always potential for change. It is just a matter of actually getting people to be able to work together co-operatively. I do not see the point of bringing back “lost” species unless we also “bring back” the habitats they require to exist with any degree of freedom. Simply adding them as exhibits in a zoo environment seems more than cruel!

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