De-Extinction, a risky ecological experiment
Feb19

De-Extinction, a risky ecological experiment

Genetic engineering may allow us to rebirth close facsimiles of extinct species. But would bringing back a few individuals of a famously gregarious bird like the passenger pigeon truly revive the species, when the great oak forests that sustained them are gone? And if it succeeds, what if the birds don’t fit in anymore in our changed world? Experience with biological invasions leads guest writer Dave Strayer, a distinguished senior scientist at the Cary Institute for Ecosystem Studies, to advocate for caution. De-extinction (bringing extinct species back from the dead) has been riding a wave of enthusiasm, fueled by Steward Brand’s TED talk and several prominent books and articles. But for a project that aspires to use materials from the past to build a better future, de-extinction is doing a poor job of using past experience with biological invasions to temper that enthusiasm. The basic idea of de-extinction is to use bits of genetic material salvaged from an extinct species (museum specimens, frozen mammoths) in cutting-edge biotechnology to create living animals in the lab, and use these lab-created specimens to re-establish populations of the extinct species in the wild. Actually, as Beth Shapiro described in her excellent book How To Clone a Mammoth, the end product isn’t literally the extinct species, but an animal with some of the genes of the extinct species (the passenger pigeon) and some of the genes of a living relative (e.g., the band-tailed pigeon), which hopefully looks and acts something like the extinct species. We might call this new species “passenger pigeon v.2.0”. I don’t need to explain the appeal of “de-extinction”. Besides using our powers to bring back charismatic species, de-extinction could restore vital functions that these lost animals performed, and thus benefit other inhabitants of their ecosystems. De-extinction is also almost irresistibly cool (come on! Bringing mammoths back from the dead?). Much of the discussion about de-extinction has focused on the technical challenges of resurrecting extinct species, the problem of choosing which species to revive, and the danger that de-extinction could divert attention and resources away from badly needed programs to prevent further extinctions. These serious problems deserve careful consideration, and are well treated in Shapiro’s book and elsewhere. But focusing on these problems can distract us from what may be the central risk of de-extinction: that its ecological effects could be large, and hard to predict and manage. We have learned from biological invasions that putting new species into ecosystems can have large economic and ecological effects, sometimes positive and sometimes negative, but almost always difficult or impossible to predict or control. Familiar examples include rabbits in Australia; or zebra mussels, emerald ash borers,...

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Reviving extinct genetic diversity #Resurrection Ecology

Is it time to define a new field? By Nadine Lymn, ESA public affairs director This is the first in a series of EcoTone posts on a recent TEDxDeExtinction event. You can watch the presentations, hosted by the National Geographic Society, here.  The talks will be edited and posted to YouTube in a few weeks.  NGS showcases de-extinction in the lead story of its April issue here.  “Maybe it’s time to coin a new term,” said Stanley Temple, a long-time conservation biologist who played key roles in preventing species such as the Peregrine Falcon and Whooping Crane from going extinct.  We were already well into the ‘Why & Why Not’ portion of TEDxDeExtinction on Friday, March 15, and it was clear that Temple, the man who occupied Aldo Leopold’s chair at the University of Wisconsin for 32 years, has deep reservations about reversing extinction through genetic engineering.  But he also clearly believes that conservation biologists need to be part of developments as the quest to revive extinct species inevitably moves forward.  Thus: “Resurrection Ecology.” Update [3/21/13, 4 PM] Temple told me he misspoke and meant to say “Resurrection BIOLOGY” since resurrection ecology has been applied to a different topic–limnologists who dredge up eggs from lake sediment to reconstruct past community structure. After listening to 6 hours of TEDxDeExtinction presentations last Friday, my head was spinning with gripping stories of charismatic and extinct species such as the Thylacine (a meat-eating marsupial—its name means dog-headed, pouched one), the biological, ethical and political dilemmas of “bringing back” species, and descriptions of the genetic techniques underway to make this is a reality. Several themes threaded throughout the event.  Here are two of them that are closely intertwined: 1. A strong concern that revival of extinct species could make current efforts to save endangered species even harder, and 2. The potential for gene technology to help save today’s endangered species. To the first theme: “We’ve got our hands full” trying to save what’s still here now, said Stanley Temple. Temple, a professor emeritus at the University of Wisconsin, is worried that de-extinction efforts could destabilize already difficult conservation efforts. We already have a tendency to rely on technological “fixes”, he said. If extinction isn’t forever, then the attitude could become, ‘let it go extinct, we can always bring it back later.’ But are too many of us already either unconcerned or feeling helpless about the many species slipping into extinction?  Would revival of extinct species give a green light to a more cavalier attitude towards loss of species? Rutgers University biology professor David Ehrenfeld wants people to consider this: While some are talking about...

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A perspective on ecological consequences of GM crops

This post contributed by ESA member Sean Hoban, a post-doc in conservation genetics at the University of Ferrara, Italy. In the opening pages of his book, Omnivore’s Dilemma, Michael Pollan quotes agrarian writer Wendell Berry in reminding us that, “Eating is an ecological act.”  Simultaneously, eating is also a political act.  Indeed, in the past year, headlines about local food and the US Farm Bill have reminded us of the interplay between agriculture, government policy, and the environment.  Food choices are complex, requiring diverse knowledge to understand the consequences of our choices, especially regarding genetically modified organisms (GMOs), one of this years’ most hotly debated topics.  GMOs are crop varieties that have been engineered to carry genes for desirable traits, taken either from other species or synthesized in the laboratory.  Such crops now make up more than 90% of sugar beet and cotton grown in the USA, and 88% of corn. Most of the debate about GMOs (understandably) centers on human health, but GMOs also influence other aspects of social-ecological systems.  This post looks at a few basic ecological concerns, which have not received much mainstream attention.  The Ecological Society of America (ESA) published a position statement in 2005 that explains these and other issues in detail.  Wikipedia has a thorough article on many benefits and costs of GMOs. While GM crops have been around since the mid-1990s, a lot is happening in 2012.  In November, Californians will vote about GMO labeling, while recently a similar “Right to Know” bill was abandoned in Vermont (after legal threats from agribusiness titan Monsanto).  Russia recently banned imports of GM corn based on a recent controversial French study that claimed to have demonstrated a link to cancer.  And next year, the US Supreme Court will consider a lawsuit between Monsanto and an Indiana farmer who unknowingly planted patented GM seeds. One big ecological concern is the potential for GM traits to “escape” into other species by hybridization.  A common GM trait is resistance to particular types of herbicides, such as glyphosate, so strong herbicides can be used to control weeds without affecting crops .  Other GM plants produce their own insecticides, such as Bt toxin, to prevent pest damage and require less pesticide application.  Future GM crops might be created to have higher nutritional value (e.g. to produce particular vitamins) or tolerate environmental stress.  The worst-case scenario sometimes portrayed is that such genes could escape into plants outside cultivation, creating super weeds (weeds resistant to herbicides) or otherwise altering a plant’s ecosystem role or relative fitness (as shown in squash) due to toxicity, growth habits, or nutrient value, with cascading ecosystem effects...

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