Can we cope with putting ourselves in the evolutionary picture?
The news that humans are clearing the planet of our natural neighbours is unavoidable. Excepting the odd success story conservationists appear to be fighting a losing battle. At the same time the increasingly sophisticated biological tools we have at our fingertips have some scientists mooting putting them to use in pursuit of saving species. Our understanding of the human impact on ecosystems also continues to grow, asking tricky questions of what conservation is trying to achieve.
The most headline grabbing scientific fix is ‘de-extinction’; the use of biotechnology to resurrect extinct species. The prospect of bringing back a woolly mammoth was kindled earlier this year by the discovery of soft tissue, potentially containing useable DNA, in the carcass of a mammoth exposed by thawing Siberian permafrost. Although given cautious credence by such heavyweights as Sir Ian Wilmut, father of Dolly the sheep, the achievement would be more an impressive scientific novelty rather than a real contribution to conservation.
But existence of biological samples from more recently extinct species means it is theoretically achievable to bring back iconic casualties of human expansion like the passenger pigeon of North America. Unfortunately this doesn’t amount to a foolproof method for winding back the clock to more biologically abundant days. Extinction events result from environmental change, most often through human settlement, so there would need to be large scale revival of habitats for a successful Lazarus attempt. There may be some cases where resurrection and reintroduction is possible, say for island species wiped out by rodents who can subsequently be eradicated. But de-extinction is sadly no silver bullet.
Other genomic techniques, however, may hold more promise. Professor Michael Thomas and colleagues have suggested that genetic engineering techniques could be used on precarious wild populations to bolster their chances of survival. Injecting genetic diversity by cross breeding individuals from a vulnerable population with a related subspecies has already been used successfully, doubling the population of the Florida panther. Genetic modification is another step along the same road.
For many environmentalists GM is still a blacklisted technology, despite prominent figures like Mark Lynas reneging on former rejection of its use. The Golden Rice debate is drawing a line in the sand between those who reject GM for being GM, and those who are willing to consider its use when not in the hands of big biotech. Some conservationists might be reassured that no one is going to make a profit from using GM technology to protect species, but the purposeful release of an adaptive allele into wild populations is a weighty intervention whichever side of the GM fence you sit on.
We engineer our crops and livestock, whether slowly through conventional means or more rapidly through GM, to have traits which increase yield and reduce expense for farmers. But these traits are almost never adaptive in the wild so are unlikely to spread their genes to much effect. Purposefully introducing traits which offer wild animals an advantage, however, makes them far more likely to survive and echo down the generations. Such ‘facilitated adaptation’ is like Richard Dawkins’ blind watchmaker of evolution handing the reins to his clumsy, but sighted, human apprentice. Whether the conservation community can stomach the idea is yet to be seen but faced with the mounting pressure of habitat loss Thomas observes that “for some species… facilitated adaptation could turn out to be the only viable remedy.”
Conservation by its nature idealises a picture of the wild from the past. But evolution by its nature is not static
Yet this ever gloomier picture may demand a fresh look. Chris Thomas, professor of conservation biology, suggests a recalibration of the lens through which we view biological diversity. For him, the apocalyptic headlines of mass extinction are only one side of the story, and not enough attention is given to the biodiversity caused by humans changing the environment. As non-native species hitch a ride with humans round the globe, they become established in new locations, adapt to their local environment and can become reproductively distinct from their originators. Species have found their way to new territories over ice bridges or on floating rafts throughout evolutionary history and we are just the most recent vehicle. The cases where invasive species wreak havoc on their native neighbours hog the limelight; the devastating cane-toads of this world are vastly outnumbered by benign invaders that rub along with everyone else.
Not that conservationists have been conning us all this time. New species resulting from human changes to the environment have not replaced in number those made extinct, and few would counsel abandoning conservation. But Thomas suggests efforts to root out some invading species are a waste of resources and that it is worth considering why we tend to value old inhabitants over new. After all, red squirrels are pretty cute but grey squirrels are too.
Moreover, as a result of the creation of human habitats like farmland and cities there is a greater diversity of environments, able to support greater biological diversity, and incredibly “evolutionary origination is accelerating”. Conservation by its nature idealises a picture of the wild from the past. But evolution by its nature is not static but in a state of constant flux in which humans are currently playing an important part. We can minimise our most destructive tendencies but we can’t take ourselves out of the picture.
In a rousing TED talk George Monbiot dreams of a re-wilded Western Europe where “mass restoration of ecosystems” would give a “portal into an enchanted kingdom” roamed by ancestral megafauna. In such a dream world the resurrection of woolly mammoths would be more than a scientific vanity project, and aurox, sabre-tooth tigers and the bizarre menagerie of paleolithic beasts could follow. But it’s a world without much room for human inhabitants and the alternative reality needn’t be a dystopian wasteland, devoid of life. We have the tools and knowledge to retain what exists, if carefully managed and cautiously approached. And what’s more, there is new wonder to be found in the ingenuity of life to exploit ecological niches of our own creation.
This post is part of 5 Viridian Years, a month-long re-examination of science-fiction author and design critic Bruce Sterling’s attempt to engineer an avant-garde bright green design movement in the dying days of the 20th century. Five years after the project ended, we are revisiting its goals, methods, impacts, and offshoots. Want to take part? Contact email@example.com.