Why the Threat of Species Extinction Isn't the Right Way to Approach Conservation
The following excerpted is from Rise of the Necrofauna: The Science, Ethics, and Risks of De-Extinction by Britt Wray, published October 2017 by Greystone Books. Reproduced with permission of the publisher.
Extinction in the Anthropocene
Today’s sixth mass extinction is similar to the other five in that it represents a giant loss of biodiversity in an incredibly short amount of geological time. According to a 2014 publication in the academic journal Science, of the 5 million to 9 million animal species that we know about, which is a conservative guess, anywhere from 11,000 to 58,000 are vanishing per year. Those estimates do not take into account local extinctions, called extirpations, in which the species still exists elsewhere. A study published in 2015 claims to show “without any significant doubt that we are now entering the sixth great mass extinction event.” The researchers looked at vertebrates, the most extensively studied group of animals, which includes mammals, birds, reptiles, amphibians, and fish, and provided conservative estimates of the number of species that had gone extinct since 1900. Despite their cautiousness, they could still show that 468 more extinctions had occurred than would be expected under normal geological circumstances—a number believed to be around 9. For the invertebrates—land-crawling critters without spines—the data is much less complete. But research suggests that invertebrates are in even more trouble than their bony-backed counterparts. It is estimated that 26 percent of mammals will be wiped out if the current extinction rate continues, and some have said that the extinction rate will increase from 1,000 times as high as the natural background rate—the current situation—to 10,000 times as high in the future.
The impact of the Anthropocene on species extinctions is unclear. On the one hand, some scientists say humans have ushered in the sixth mass extinction by expanding our societies across the globe in the truest Anthropocene fashion. On the other hand, the pressure that the Anthropocene puts on ecosystems also forces new species into existence. Chris D. Thomas, a professor of conservation biology at the University of York in the UK, argues that hybridization and the blurring of species lines, as accelerated by the Anthropocene, need not be maladaptive. Throughout human history we’ve translocated species on purpose, spread invasive species by accident, and brought formerly separated species into contact with each other by remodeling their habitats. Hybridization flourishes where humans shape the land, affecting the dispersal of animal populations. The Arctic Spring now arrives roughly one week earlier than it used to, and the winter freeze sets in one week later than it once did, but animals compensate for the temperature change by moving into new ranges. Along the way, they might meet other species on the run from melting sea ice and mate with them, creating a generation of new hybrid species. According to Thomas, “Speciation by hybridization is likely to be a signature of the Anthropocene . . . Populations and species have begun to evolve, diverge, hybridize and even speciate in new man-made surroundings.” Climates change, habitats morph, and new creatures come into view.
Stewart Brand recognizes the Anthropocene’s creative potential for speciation: “Any creature or plant facing a shifting environment has three choices: move, adapt or die. Evolution is far more rapid and pervasive than most people realise.” He points out that evolutionary change does not always mean evolutionary disaster—and climate change doesn’t mean that all species will die in its wake. Some might move into new areas beyond their historical distribution, expanding their native range. In this sense, the Anthropocene might devastate some species, but it might also accelerate the evolution of others.
If hybridization in the wild can allow creatures to survive anthropogenic change, what might that mean for hybrid species that are intentionally created? When genes from extinct species are inserted into the genomes of their living relatives, will de-extinction become an asset for the Anthropocene? As other human-discovered technologies like CRISPR and cloning allow the threat of extinction to be alleviated from inside a petri dish, what types of environmental change will the creatures they produce be able to cope with when they’re reintroduced in the wild?
The Anthropocene is creative, an idea Brand pushes to its edge. He has argued that mass species extinction is not the problem—the real issue is the way we use its narratives to stir panic in the minds of the public. Our hearts ache for species as they disappear one by one, but, Brand says, the decline of many nonextinct wild animal populations is a much greater threat to conservation than the obliteration of single species. Ecosystems are affected not just by how many species exist in them but also by how many individual animals are there to play out their ecological roles. This is what’s known as bioabundance, without which a substantial number of important ecological processes—like grazing, planting seeds, and enriching the soil—might happen too infrequently to maintain an ecosystem’s productivity. In this sense, the more individual creatures there are, the more ecosystem richness there will be. “Viewing every conservation issue through the lens of extinction threat,” Brand says, “is simplistic and usually irrelevant. Worse, it introduces an emotional charge that makes the problem seem cosmic and overwhelming rather than local and solvable.”
The philosopher Timothy Morton speaks of hyperobjects—entities spread so vastly across space and time that we can’t see their edges. Climate change is a pertinent example. Mass extinction also aptly fits the bill. When you can’t see where a hyperobject stops or starts, you might not know where or how to intervene. Hyperobjects make us feel small and helpless. In light of extinction, Brand states, “The core of tragedy is that it cannot be fixed, and that is a formula for hopelessness and inaction. Lazy romanticism about impending doom becomes the default view.”
As a champion of de-extinction, Brand understandably wants us to feel that it can help us do something proactive about species loss instead of give into environmental pessimism. And by steering us away from the hyperobject at hand and focusing us squarely on pragmatic goals—such as increasing the number of animals out there—he presents the quest for bioabundance as convincingly worthwhile. But do we really want to obliterate all distinction between the kinds of species loss we are concerned about and the degree of that loss? When a species goes extinct, a particular way of life is lost forever. Creating new transgenic animals in the name of conservation may be fine in cases that have been thoroughly thought out. But it does not account for the fact that when a certain species disappears, its unique flavor of existence, which had intrinsic meaning and value to other life forms, fades away as well. What would we miss if bioabundance were all that mattered? Perhaps if bioabundance was our foremost concern, we’d risk undercutting the moral value of living species and all that their existence has brought into the world so far. Call me old-fashioned, but why shouldn’t that matter more?
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