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The Niau atoll in the South Pacific Ocean, taken by the European Space Agency; Courtesy of Flickr user trackrecord

The plight of Pacific Islanders has been the center of the debate over the human toll of climate change. Last month, the Federated States of Micronesia filed an objection against one the dirtiest power plants in Europe, arguing that unchecked carbon emissions could eventually drown this nation of 600 islands. Another low-lying nation, Tuvalu, which sits halfway between Hawaii and Australia, has long claimed that its entire population may need to be evacuated in the next few decades.

But a new study by Arthur Webb at the South Pacific Applied Geoscience Commission in Fiji and Paul Kench at the University of Auckland in New Zealand throws some cold water on these tropical predictions. Webb and Kench examined satellite images of 27 Pacific islands dating back to the 1950s. Although sea levels have risen 120 millimeters in that time, most of those islands, including seven in Tuvalu, have either stayed the same size or gotten bigger. Their resiliency against rising seas comes from the fact that they are made up of chunks of coral reef that break off during storms and are deposited on their shores.

“It has been thought that as the sea level goes up, islands will sit there and drown,” Kench told New Scientist, “But they won’t. The sea level will go up and the island will start responding.”

The findings may be good news for island residents, but it doesn’t mean they can’t stop worrying. The rate of sea level rise could accelerate in the next century, and it’s not clear whether the coral atolls can keep up. Finally, even though the islands change shape, it doesn’t mean that they will all remain habitable. Then again, I wouldn’t have thought they were habitable some 2000 years ago, when the first island-hoppers arrived from Tonga and Samoa.

Much thanks to Brendan Borrell for guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.

Photo of Genyornis rock painting, courtesy Ben Gunn

A pair of giant, extinct birds depicted on a rock in Australia could be the continent’s oldest work of art.

When humans first set foot on Australia’s northern shores some 50,000 years ago, Genyornis newtoni, a bird three times the height of an emu, would have been an important item on their menu. This red ochre painting of the extinct bird—the first of its kind—was discovered in a narrow rock shelter in Arnhem Land two years ago, but its significance was recognized only this month after a visit by archaeologists.

“It means either that it was painted at the time of the Genyornis bird, or that the Genyornis had lived longer than we thought,” archaeologist Ben Gunn told the Agence France Press.

Some of the oldest rock paintings in the world are found in Australia, but putting a hard date on these ancient artworks remains a technical challenge. Scientists are rarely able to use chemical methods to estimate the ages of organic pigments, and must ballpark dates by judging the sophistication of the painting or its geological context. That’s why finding the depiction of an extinct animal is of such importance. Last year, for instance, scientists identified a marsupial lion painted on rocks in the Kimberley region, suggesting those paintings are at least 30,000 years old.

Genyornis is thought to have gone extinct relatively soon after humans arrived on the scene, which means the newly discovered painting could be 40,000 years old, making it the oldest in Australia, if not the world.

But, like most topics in the study of cave art, that interpretation has not been unanimous. Robert Bednarik of the International Federation of Rock Art Organizations told The Australian he was not convinced it depicted a Genyornis and he thought that it was only 5000 years old. “I am not aware of any painting or even petroglyph of an animal anywhere in the world that is more than 10,000 years old located outside of caves.”

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.

For the first time, scientists have tracked the movements of tropical orchid bees using radio-transmitters. The bees, studied at the Smithsonian Tropical Research Institute in Panama, fly up to 3 miles from their home areas and patrol up to 285 acres of rainforest in their hunt for food and mates.

Orchid bees congregate on a scented stick in Panama, photo by Brendan Borrell

Just thinking about orchid bees brings back the minty odor of methyl salicylate and the cinnamon scent of eugenol, fumes of which I inhaled nearly every day during my PhD research. Male orchid bees collect scents from the specialized orchids they pollinate, and an old tropical “magic trick” is to set out filter paper loaded with the gunk and watch these metallic bees appear. The bees likely harvest the scents for mating, but no one knows for sure. What scientists do know is these bees fly really fast and really far.

In one failed attempt to study the movements of orchid bees, my intrepid assistant Matt Medeiros balanced himself on the prow of our motorboat holding an airspeed gauge in one hand and a butterfly net in the other. The goal was to measure their flight speeds as they raced across the Panama canal. We could have used more horsepower. Our success rate was less than impressive.

Even then, I remember there was talk of attaching radio transmitters on bees. Martin Wikelski of the Max Planck Institute of Ornithology in Germany had set up a series of radio towers on Barro Colorado Island, which Megan Gambino recently wrote about for Smithsonian.com. The towers have allowed monkey, sloth, and frog researchers automatically track their research subjects, but back in 2002 radio-tracking insects still sounded pretty far-fetched. Then, in 2007, a graduate student Alex Eaton-Mordas of the University of Arizona at Tucson, told me it finally happened. He went to Panama that March, attached transmitters on the biggest bees, and managed to get up to 10 days’ worth of data. For technical reasons, they had to track them with hand-held and helicopter-mounted antennas.

The study has now been published in the journal PLoS one and there’s even video. The study demonstrates once and for all that male bees are not “vagabonds,” as one tropical ecologist has suggested, but they maintain a home area they retire to at night. It’s a nice coup, but the transmitters are still on the heavy side, weighing about half as much as the insects. The bees can normally carry that much nectar, but it definitely slows them down.

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.

Mangrove forest, courtesy of Flickr user peyri

There’s nothing that conservationists would like better than proving that protecting nature is good for people too, which is one reason why I try to remain skeptical about such claims. After all, when you fence in forests and wildlife, you’re eliminating an important source of income, food and land for locals. In addition, protected areas are often located in the most impoverished areas, where communities have little chance of opposing pressure for conservation.

But a study published this week in Proceedings of the National Academy of Sciences provides some powerful new evidence that protected areas in Costa Rica and Thailand have boosted livelihoods. Although people near protected areas are still less well-off than the rest of the country, researchers found this had more to do with confounding variables such as forest cover, land productivity and access to transportation, which influenced both the placement of parks and the livelihood of residents. After removing those effects, the researchers found that the presence of parks reduced poverty in Costa Rica and Thailand by 10 percent and 30 percent, respectively.

The new study isn’t the only evidence that conservation is good for the economy. In the current issue of Nature Conservancy magazine, I examined the value of mangrove forests to local communities. Off the Gulf of California in Mexico, for instance, fishermen living near the biggest mangroves reel in the most fish and crab. Specifically, each acre of mangrove brought in about $15,000 per year in seafood, a dollar amount 200 times higher than the forest’s timber value.

Mangroves also save lives. Their spidery roots can reduce the force of waves pummeling the land during severe storms. Saudamini Das, an economist with India’s Institute of Economic Growth, estimates that mangroves saved nearly 20,000 lives during the 1999 Orissa Cyclone in the Indian Ocean.

On the other hand, not every ecosystem will have as many tangible benefits as mangroves, and not every country can be Costa Rica, which has set aside a quarter of its land for conservation. As the Nature Conservancy’s chief scientist, Peter Kareiva, puts it, “Quantifying ecosystem services will not protect all of the nature you want to protect, but it will generate public support for an awful lot of conservation.”

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.

Wild muscadine grapes, courtesy of Flickr user The Natural Capital

First it was pet turtles and now it’s wine grapes—I just can’t stop thinking about what it means to be native. The United States ferments 700 million gallons of wine each year, most of it from the sugary mash of Vitis vinifera, a grape species imported from the Old World. Yet North America boasts a total of six grapes, including the subtropical muscadine (Vitis rotundifolia), the cold-hardy frost grape (Vitis riparia) and the fox grape (Vitis labrusca) from the Northeast. What gives?

About 7,400 years of Vitis vinifera winemaking, as I wrote for Scientific American last year. But just because V. vinifera happened to be the first grape humans began domesticating, doesn’t mean it has to remain the ne plus ultra of the grape world.

The online wine magazine Palate Press has an interesting article about American pioneers like the late Elmer Swenson of the University of Minnesota who hybridized the Frost grape with the European grape to develop the St. Croix. The University Web site says “it is still too soon to judge its wine quality potential.”

Other researchers, such as Bruce Reisch of Cornell University and independent breeder Lon Rombough, are trying to create new grape cultivars for homegrown wines. But so far the grapes’ potential has been limited to niche markets and growing regions where the climate is too warm or too cold for V. vinifera. “Most people have never heard of a Frontenac or a Muscadine, much less know how to match one with a steak or a penne pasta,” David Mark Brown writes at Palate Press.

In fact, America’s favorite oenophile, Thomas Jefferson, tried and failed to grow European grapes at Monticello. According to a new book, The Wild Vine: A Forgotten Grape and the Untold Story of American Wine, Jefferson should have gone local. Just a few years before his death in 1826, a Virginia physician named Daniel Norton succeeded in hybridizing V. vinifera and a Midwestern native, Vitis aestivalis. The Norton is still grown in Virginia and is the cornerstone of the Missouri wine industry.

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.