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,...

Read More

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...

Read More

Easter Island’s quiet message

Ahu Tongariki, the largest platform on the island, features fifteen restored Moais. The Moai in the foreground was likely damaged in transit and never erected. Credit: Brian Wee. This post contributed by Brian Wee, chief of external affairs for NEON, Inc. The July 2012 edition of National Geographic features Easter Island – known also as Isla de Pascua in Spanish and Rapa Nui by the local population.  Rapa Nui is famous for the silent stone statues called Moais that are scattered around the island.  In late May of 2012, my partner and I spent four days exploring Rapa Nui.  A remote speck of land no larger than Washington, DC in the Pacific and accessible by a five-hour flight from Santiago, Chile, Rapa Nui is often referred to as one of the most isolated, inhabited areas.  One skillful (and probably lucky) Polynesian expedition discovered it sometime in the 8th century.  Given the Pacific’s expanse, you have to wonder about the probability of finding such a small island in the vast ocean, and accordingly, how many other expeditions did not quite make it. Most of the Moais are located along the island’s coast, although some are also found inland.  Moais are stood on ceremonial stone platforms called Ahus, and visitors are reminded not to clamber on top of the Ahus at the risk of heavy fines.  A guidebook advocated gently shooing horses off these platforms if you come across an animal browsing on an Ahu.  Yes, horses.  They roam freely on the island.  Like the two that were wandering around the parking lot of the Rapa Nui airport after our flight landed on Monday evening.  Our Bed &Breakfast host had picked us up at the airport, but I resisted the temptation to tap his shoulder and ask “Say…. did you see those HORSES walking around in the airport PARKING LOT?”  Given that he deftly maneuvered the vehicle around the animals and didn’t say anything about them, I figured that he must have seen them.  Oh well. One of Rapa Nui’s many horses and her foal at the Ahu Tepeu site. Credit: Brian Wee By some reports, the number of horses on the island is greater than that of the roughly 5000 full-time residents.  It wasn’t long before I thought of the effects of unchecked herbivory on the structure and function of the island’s plant community.  Trees are sparse on the island, and there is some evidence that Rapa Nui once supported more trees before the human population expanded to what is thought to be unsustainable levels.  The island’s last indigenous tree – the Sophora toromiro – died in the 1950s, but...

Read More

What’s in a name? Proposed reinterpretation of key words in the Endangered Species Act

This post contributed by Sean Hoban, a post-doc in conservation biology at the University of Ferrara, Italy   How important can five words be?  Very! The 1973 Endangered Species Act states that a species may be regarded as endangered if “threatened with extinction […] throughout all or a significant portion of its range” (my underline, hereafter, SPR).  Remarkably, neither the US Fish and Wildlife Service (FWS) nor National Marine Fisheries Service (NMFS) has had an official policy on the meaning of this phrase for the thirty-nine year history of the Act.  Enter proposal FWS–R9–ES–2011–003 (summarized here), which spells out the Services’ soon-to-be official interpretation of the seemingly innocuous phrase, specifically defining the words “significant” and “range.” As a conservation biologist working for effective species survival, I would like to share my impressions of the proposal, and encourage all to participate in the public comment, extended until March 7.  How these five words are interpreted will have lasting consequences for species’ listing and subsequent recovery plans and management actions. After an insightful review of past legislative battles over SPR, the proposal gets down to business on page 5, stating that a definition of “significant” should include (a) the variable to measure and (b) a threshold for that variable.  Further, a) and b) should be based on biological and conservation criteria. We would probably all agree here!  But read on, controversy awaits. As explained on page 8, in the preamble to the proposal, a portion of a species’ range may be “significant” with respect to a species’ resiliency (ability to recover), redundancy (multiple, distributed “backups”), and/or representation (range of variation).  Also important are “abundance, spatial distribution, productivity, and diversity of the species.” However, these key variables are lacking in the actual proposed interpretation (page 16/17); the actual definition of a SPR is very succinct: “without that portion, the species would be in danger of extinction. If so, the portion is significant.” It is therefore arguable whether the new phrasing improves specificity; this wording seems as open to interpretation and debate as ever.  Further, as noted in several ongoing dialogues on Ecolog-l, and summarized in an open letter by the Center for Biological Diversity, this could “result in species that are severely endangered in portions of their range being denied protection because they are secure in some portion of their range even if that portion is just a fraction.”  Specific examples are argued in recent news articles and blogs.  These commentaries question whether (in the proposal’s words) “the draft policy would result in the Services listing and protecting throughout their ranges species that previously we either would not have listed, or would...

Read More

In Ecology news- climate change, wine, volcanoes, automated birdsong, animated krill, and the mysteries of ‘womanspace’

This post contributed by Liza Lester, ESA communications officer In the news By 2080, Adirondack communities dependent on snow for winter tourism dollars may be struggling, says a report commissioned by the New York State Energy Research and Development Authority. But the Finger Lakes wine country may benefit from a longer, warmer growing season and more water. Touching lightly on a full spectrum of consequences, from ecological shifts and agriculture to human health and infrastructure, the report summarizes risk potential across the state…based on sources that are probably available somewhere. Leslie Kaufman reports in the New York Times. An uncertain future climate is a big concern for vineyards. Grape varietals are sensitive to temperature and humidity, and some famous wine regions may be forced to re-brand themselves to stay in business. With decades invested in developing a productive, mature vineyard, viticulture is a long-range endeavor. Wine makers need to carefully plan new plantings of vine stocks to cope with future drought, deluges, and heat. Paige Donner covers industry strategies to predict and adapt to future conditions. In the Permian Era, 252 million years before the controversies of our own climactic changes, climate change killed most of the Earth’s species, says geologist Shu-zhong Shen and colleagues in this week’s Science Express. The culprit during the Permian was massive volcanic activity. The team collected sediment samples across southern China to produce a chronology of the mass extinction, bracketing the loss of life to a period lasting a mere 200,000 years, and confirming that land-based species died during the same period as marine species. Science writer Seth Borenstein reports for the Associated Press. Volcanoes affect the climate in our time, as well, but it’s been a long time since we’ve had one of a magnitude to produce catastrophe. On the November 4th Science podcast, Richard Stone talks about “the most dangerous volcano you haven’t heard about,” Mount Paektu at the border of China and North Korea. Slideshow.   On the blogtrail At The Last Word on Nothing, Thomas Hayden enthuses about krill feces and the delightful rise of biological diversity in pop culture, represented by the latest animated singing animals in Happy Feet Two. Jennifer Ouellette writes about an app for bird song identification in development by Ecuadoran researchers Hugo Andrade and David Puente. And the science blogs are humming with outrage over a short story published in Nature (did you know that Nature publishes fiction?). It seems that that Nature senior editor Henry Gee was looking for controversy. “I’m amazed we haven’t had any outraged comments about this story,” he commented on October 3rd, on Nature’s fiction page, “Futures,” which he...

Read More

Chickenpox sweeties and the social ecology of infectious disease

This post contributed by Liza Lester, ESA communications officer   No one speaks for the endangered poliomyelitis. No one raises money to protect the last survivors, as health workers stalk the virus through its last redoubts in India, Pakistan, Nigeria and Afghanistan. On the contrary, the WHO spends billions on hunting it to extinction. But the virus has held out longer than expected. Joshua Michaud, policy analyst at the Kaiser Foundation, thinks the polio fighters are falling behind. Guinea worm will be the next scourge to fall, he said on an AAAS panel engaged to discuss Infectious Disease: Challenges to Eradication on Monday. Why have efforts with guinea worm been so successful? a precocious Georgetown student wanted to know. Biology was on our side. There is no vaccine for guinea worm, and no medicine to cure infection. To extract the worm, you must wind it slowly around a stick as it emerges through a sore in your leg (an oft-repeated story holds that the treatment has not changed since the Egyptians of the XVIII dynasty described it in 1550 BCE, though the source appears to have been exaggerated). The process is excruciating, and it takes weeks. But we know key details of the worm’s biology that the ancient Egyptians did not. Basic technology and careful hygiene can defeat the worm. Larvae harbor in the bodies of invisible copepods, “water flies” tiny enough to swallow. Once swallowed, female larvae nestle against the long limb bones of their hosts, growing up to a meter in length over the course of a year. They surface inside a burning ulceration that sends their victims running for a dip in a cool pond—and the next generation of larvae escape to start the cycle of life anew. The good news, said Michaud, is that guinea worm does not have another host. It has no environmental bolt hole to hide in while under siege, only to emerge when health forces are not looking. It needs humans. And affected people are visibly affected. Break the cycle for one year, and you can free a communal water source, and its community, from the worm. Copapods may be microscopic, but a simple nylon strainer on the end of a drinking tube saves you from swallowing them (although not bacterial and viral parasites that might also lurk there, interjected Dennis Carroll, in charge of avian flu and other emerging threats at USAID). Help the infected, persuade them to stay out of drinking water sources when their worm breaches, and you break the cycle. Success requires the help and good will of village elders. The Carter Foundation has been courting good...

Read More

National Parks, dance lessons from a spider and bellybutton biodiversity

National Parks Week: In addition to Earth Day activities, this week is also National Parks Week. Allie Wilkinson of the blog Oh, For the Love of Science! paid tribute with a mini-travel guide on Acadia National Park in Maine; the post is complete with trail information and scenic views (see below video). “Maine may as well be my home away from home,” Wilkinson wrote. “I’ve gone up just about every year since I was a baby, at LEAST once a year (but usually end up going 3 times a year), and I always go to the same spots.  Each year, the big trip in August takes me to Mount Desert Island, home of Acadia National Park.” Read the full post at “National Park Week: Acadia National Park.” Busy billionaire: Richard Branson has moved from space to deep sea exploration, and, most recently, he has made the news for his plan to introduce endangered ring-tailed lemurs to Moskito Island in the Caribbean. Branson stated in The Guardian that the decision is intended to “…create a second island habitat [for lemurs in Madagascar,] and the conditions on Moskito are perfect.” However, many are concerned about the ecological consequences of releasing these omnivores. As explained in Smithsonian’s Surprising Science blog, “Conservation plans rarely begin with (or even include) the introduction of a non-native species. And though lemurs surely are adorable, they ‘could damage native flora and fauna on the island, particularly reptiles such as the stout iguana, turnip-tailed gecko, and dwarf gecko, as well as birds’ eggs,’ [conservationist Erik Patel] says.” Dance lessons: While we tend to think of dancing as a source of rhythmic self-expression, just like in other animal species, dancing can also be an effective way to attract a mate. Small, songless birds called manakins, for example, display an impressive moonwalk to attract a mate. And, as described in the blog immunoBLOGulin, “If you want to learn some sweet moves, take a lesson or two from the Australian Peacock Spider. While it’s less than 1cm in length, it can really put on a dancing show…” The jumping spider (Maratus volans) has a colorful flap used during the dance (see below video). Read more at “Lessons from the Peacock Spider: How to attract a mate.” Bright bills: “When it comes to mallard bills, brighter is better: A bright yellow bill is duck-speak for ‘I’m healthy,’ attracting more female ducks than dingy green ones,” Patrick Morgan reported for Discover’s Discoblog. That is, researchers found that male ducks with brighter bills had semen with greater antibacterial properties, reducing the female ducks’ risk of contracting bacteria-related sexually transmitted diseases. The researchers discoved that...

Read More

It takes more than climate change to cause amphibian decline

This post contributed by Monica Kanojia, Administrative Assistant/Governance for ESA. Amphibians have been around for hundreds of millions of years. They have survived numerous extinction events and yet somehow, in the past two decades, their numbers have been in severe decline. The population changes have been linked to many factors, including climate change and disease, habitat destruction and water pollution. Studies indicate that amphibians are sensitive to all of the proposed variables—not just one root cause. A unique quality of amphibian biology is their transdermal water uptake ability. Transdermal uptake allows for nutrients to be delivered across the skin. For example, the skin of a frog allows for the direct exchange of oxygen, carbon dioxide and water from the environment. While in ideal situations this would be beneficial, it currently poses a threat to amphibian populations. Overexposure to any nutrient can be lethal to an organism. With increased rates of carbon dioxide in the atmosphere, heavily polluted water and loss of water, amphibians’ ability to survive is diminishing. A majority of amphibian species go through reproductive and developmental stages that require a body of water. The eggs of amphibians are not as resilient as reptile or bird eggs because they are jelly coated and unsuitable for development on land; therefore, amphibians must return to water to reproduce. Increased agricultural and industrial run off and poor waste management has led to a decline in the quality of water available for amphibians. The main types of chemical contaminants affecting amphibian environments are pesticides and herbicides, heavy metals, increasingly acidic water and nitrogen pollution. According to a study published in the journal Environmental Health Perspectives by Tyrone Hayes from the University of California, Berkeley and colleagues, pesticides commonly used in cornfields in the western United States have adverse affects on amphibian larval growth and development, immune system and the size prior to and after metamorphosis. High levels of pesticides enter streams and groundwater as water runs off of farms, ranches, golf courses and suburban areas. While organic and low-risk pesticide use is encouraged by the U.S. Environmental Protection Agency, it remains predominantly unregulated… That is, the EPA lists guidelines for how to safely use pesticides for commercial and agricultural needs, but it does not strictly regulate what can and cannot be used. Herbicides, on the other hand, are made to disrupt photosynthesis capabilities of plants and were thought to have little to no effect on fish and wildlife.  But, as Science Daily reported in 2008, studies have revealed otherwise. For example, atrazine—one of the most commonly used herbicides on golf courses, home lawns and soybean and corn crops—is responsible for lethal changes...

Read More