The Legacy of Lonesome George

Home , Diego (tortoise), Lonesome George

NEWS IN FOCUS PHYSICS Theorists scour data GENOMICS Gene-expression PUBLISHING United SPECIAL SECTION Science on Higgs for hints of new data troves reach critical Kingdom takes plunge goes to the London physics p.281 mass p.282 into open access p.285 Olympics p.287

week, Nature joined experts in Puerto Ayora on the island of Santa Cruz for an international workshop dedicated to the memory of Lone- some George. The meeting aimed to galvanize efforts to prevent the loss of other Galapagos

R. BUENDIA/AFP/GETTY tortoise species and their habitats. “One species is very important, but most important are the ecosystems,” says Washington Tapia, director of conservation and sustainable development for the Galapagos National Park. George was discovered on the island of Pinta in 1971, and was transferred to the Charles Darwin Research Station in Puerto Ayora the following year. Conservationists launched a long and frustrating campaign to persuade the reptile to mate with females from other Galapagos islands1. Hopes soared in 2008 when handlers discovered eggs in the enclo- sure he shared with two females, but the eggs were found to be unfertilized2. On 24 June this year, Fausto Llerena, a ranger at the Galapagos National Park and George’s long-term keeper, found him slumped in his corral. Within hours, Llerena was help- ing to carry the tortoise’s corpse, trussed onto a wooden frame, into a chilled storage chamber. In 2008, Ecuador was the first country in the world to amend its constitution explicitly to grant basic rights to nature and its inhabit- Lonesome George, who died last month, was the last of the Pinta giant tortoises. ants. As a consequence, George was accorded a full necropsy, performed by Marilyn Cruz, CONSERVATION a veterinary surgeon who is the coordinator of Agrocalidad in Galapagos, the government agency that oversees agriculture and biosecu- rity on the islands. “The last thing we need to The legacy of do is to investigate his tissues,” says Cruz, cur- rently the legal guardian of George’s remains. Cruz found nothing obviously wrong with the tortoise; she concluded that he probably Lonesome George died of natural causes. But, she says, George’s “liver and kidneys appear to have some abnormalities”, which the laboratories need to Tortoise’s death spurs Galapagos conservation efforts. investigate in depth. Cruz also took a sample of George’s skin cells for culturing; they could BY HENRY NICHOLLS IN PUERTO AYORA, (Chelonoidis abingdoni), and it is too soon to eventually be used to generate stem cells and GALAPAGOS know whether biotechnology can reverse the sex cells, or in reproductive cloning. extinction. But scientists have made the first But the cells had to be frozen within days of ven in death, Lonesome George’s star step: in the days after George’s death, they George’s death. Establishing a viable cell culture power burns brightly. After the iconic raced to keep his cells alive, collecting tissue “is highly correlated with the freshness of the giant tortoise died last month, Ecuado- and ferrying liquid nitrogen to his remote sample”, explains Oliver Erian President Rafael Correa mourned the rep- home in Ecuador’s Galapagos Islands to pre- NATURE.COM Ryder, a geneticist at San tile’s loss in an address to the nation, expressing serve samples that might one day yield a viable To read a News Diego Zoo in California hope that “one day, science and technology will cell culture. Feature on turtle and champion of the Fro- be able to reproduce him, to clone him”. Even if the bid fails, George’s death is already conservation, see: zen Zoo, a facility con- George was the last of the Pinta tortoises offering hope for other giant tortoises. Last go.nature.com/merukq taining cryopreserved

cell cultures from more than 9,000 individ have their threat categories downgraded. But researchers went on to show5,6 that Wolf is also uals representing nearly 1,000 endangered the Pinta tortoise — still listed as ‘Extinct in harbouring descendants of the long-lost Flo- species. Ryder arranged for colleagues in San the Wild’ — will be recategorized as ‘Extinct’. reana lineage and the recently lost Pinta one. Diego to deliver tissue-culture medium and the To some visitors, the giant tortoises on one The researchers hope to mount a return cryoprotectant dimethyl sulphoxide to Ecuador island of the Galapagos might look much the expedition to Wolf volcano next year, in an on the first available flight. same as those on another. But as Charles Dar- effort to locate the Floreana- and Pinta-like Cruz hurried to secure a local supply of liq- win came to appreciate after his brief sojourn tortoises. In theory, these animals could be uid nitrogen. There were two liquid nitrogen in the Galapagos in 1835, each island or main taken off Wolf volcano for captive breeding. tanks on Santa Cruz, used for freezing semen volcano seems to have its own distinct type Floreana has been heavily affected by habi- for the artificial insemination of cattle in the of tortoise, and all are diverging into sepa- tat destruction and introduced species, and highlands. By commandeering one tank, rate species. Genetic differences suggest that has been without tortoises for more than Cruz got hold of enough liq- 150 years. But the Floreana-like uid nitrogen to keep George’s tortoises on Wolf could help with cells safely frozen until top-up ENDANGERED GALAPAGOS GIANTS a long-term project to restore the Ten species of giant tortoise (Chelonoidis) remain on the Galapagos islands, and all stock could be shipped from are threatened. Estimating the number of individuals in each population is extremely island’s ecology. The situation on the mainland. Several liquid- di cult, however, and some of the data below are more than a decade old. Pinta is more urgent, and wait- nitrogen containers are now ing for a captive-breeding pro- being relayed back and forth PINTA gramme to bear fruit may not be between the continent and the an option. Much of the island’s islands to keep the cells frozen COLOMBIA original vegetation is intact, until it is decided where they C. becki but without tortoises — once

ECUADOR PARK NATL 98–111 (2004)/GALAPAGOS 3, will be stored in the long-term. ~ 8000 the island’s dominant herbi- It remains to be seen whether Wolf GALAPAGOS vore — there is a danger that C. microphyes the cells, if thawed, will yield a some plant species could be 56–075 C. darwini PERU viable culture. 89–,370 Paci c choked out and lost. Darwin Ocean With George’s demise, ten If a rapid solution cannot be FERNANDINA SANTIAGO ECOLOGIA APLICADA ECOLOGIA species of Galapagos tortoise C. vandenburghi found using tortoises of Pinta

remain. The reptiles’ popula- pedigree, it looks increasingly AL ET 5,000–0,000 C. ephippium Alcedo tions have suffered as a result 459–605 C. chathamensis likely that conservationists will RQUEZ of hunting, habitat destruc- Sierra ISABELA SANTA CRUZ ,400–2,000 introduce a species from another Á Negra PINZÓN tion and the introduction of SAN CRISTÓBAL island. “Given that tortoises from destructive species over the Cerro C. guntheri C. nigrita Española founded the original Azul 400–700 2,3–6,703 past few hundred years; some C. vicina population that landed on Pinta SOURCE: C. M are now on the increase as a ,800–2,700 and evolved into the Pinta tor- result of conservation efforts, toises, I don’t see a problem with hoodensis but with a tortoise typically FLOREANA us repopulating that island with taking 20–30 years to reach > ,700 Española tortoises,” says Cayot. Volcanoes ESPAÑOLA sexual maturity, recovery has Tortoise populations 20 km The Española tortoise was been very slow. once on the brink of extinction, Last week’s workshop took but now there are more than several years to organize, and one subject on Lonesome George’s own ancestors somehow 1,700 of the reptiles, and conservationists can the agenda was what to do with George in travelled to Pinta from the island of Española afford to consider transferring some of them the event of his death, and whether to collect about 300,000 years ago, and had been diverg- to Pinta. This kind of deliberate introduction his cells while he was still alive. With that no ing from their relatives ever since. is unprecedented in the Galapagos, however, longer possible, the workshop focused on its From a management perspective, “each so researchers are cautious. As a precursor main goal of thrashing out a ten-year plan to island is totally different”, says Cayot, who experiment, almost 40 sterilized hybrid tor- preserve the surviving animals (see ‘Endan- was one of the first researchers to carry out an toises have been introduced to Pinta, and are gered Galapagos giants’). in-depth study3 of the behavioural ecology of being tracked by satellite to see what impact “What we’re trying to do is bring everyone giant tortoises, in the early 1980s. “Pinzón has they have on the ecosystem. together” to synthesize the perspectives of rats. Santiago had pigs and goats. Pinta had For Cayot, introducing a breeding popu- ecologists, geneticists and conservation man- goats, but only for 20 years. Española had goats lation of tortoises to Pinta is a much more agers, says workshop organizer Linda Cayot, for probably 100 years,” she says. “That’s what rational proposal than a plan that relies on science adviser to the Galapagos Conservancy makes Galapagos so much fun.” cloning Lonesome George. “In 100,000 years, in Fairfax, Virginia. The outcome, she says, will One of the most fascinating populations through evolutionary processes, we’ll have be a single set of recommendations that can lives around Wolf volcano at the northern tip a Pinta tortoise in Galapagos,” she says. be delivered to the Galapagos National Park. of the island of Isabela. Over the past decade, “100,000 years is a time frame I can deal The meeting also began work to review the Adalgisa Caccone, a geneticist at Yale Uni- with.” ■ status of the Galapagos tortoises on the Inter- versity in New Haven, Connecticut, and her 1. Nicholls, H. Nature 429, 498–500 (2004). national Union for Conservation of Nature colleagues have been unpicking the ances- 2. Nicholls, H. Nature http://dx.doi.org/10.1038/ (IUCN) Red List of threatened species. The try of this mixed-up population. In a study4 news.2008.1221 (2008). tortoises’ Red List entries date from 1996 and based on blood samples from a few dozen 3. Cayot, L. J. Ecology of giant tortoises (Geochelone elephantopus) in the Galapagos Islands. PhD Thesis, are in urgent need of revision, says Peter Paul individuals, she found evidence that tortoises Syracuse Univ. (1987). van Dijk, co-chairman of the IUCN/Species from Española and San Cristóbal had crossed 4. Caccone, A. et al. Evolution 56, 2052–2066 (2002). Survival Commission Tortoise and Fresh more than 250 kilometres of sea to reach 5. Poulakakis, N. et al. Proc. Natl Acad. Sci. USA 105, 15464–15469 (2008). water Turtle Specialist Group, who attended Wolf, probably carried by pirates and whal- 6. Russello, M. A. et al. Curr. Biol. 17, R317–R318 the meeting. Some Galapagos tortoises could ers. Using DNA from museum specimens, the (2007).