Tuesday 12 February 2013

One inch Lizard

The coral reefs and beach-lined inlets look right out of a tourism brochure. Beyond that, however, the tiny island of Nosy Hara just off the northern tip of Madagascar is rather desolate. Only a few patches of forest cover the rocky bit of land, not the kind of place that looks particularly hospitable to wildlife.

Yet it is here that biologists have discovered a fascinating new species: the tiny chameleon Brookesia micra. From tip to tail, the mini-lizards measure less than three centimetres (1.2 inches), making them some of the smallest reptiles on Earth.

Mostly brown with a touch of green, the coloring of the diminutive creatures is far from spectacular. And they are unable to change their appearance like their larger cousins. Nonetheless, researchers are fascinated. "It's not the kind of thing where you have to perform extensive genetic analysis to realize that this is something new," Miguel Vences, a biologist with the Technical University of Braunschweig and the co-author of an article on the new species in the scientific journal PLoS ONE, told SPIEGEL ONLINE.

Still, Vences and his colleagues, including Frank Glaw from the Bavarian State Collection of Zoology and Jörn Köhler of the Hesse State Museum in Darmstadt, have taken a closer look at the lizard's genetic makeup -- and that of other tiny chameleons they found in neighboring regions of Madagascar. In total, the researchers discovered four new species of miniature saurians.

They have also found "surprisingly large genetic discrepancies" between the quartet of new discoveries, despite the fact that they all look very much alike. Their evolutionary paths would seem to have diverged many millions of years ago.

"How, though," wonders Vences, "did the animals manage to survive for so long in the small fragments of forest where they live?" Their habitat on Nosy Hora is hardly even 50 hectares (125 acres), he estimates. About the size of 70 football fields.

"We don't know much more about the animals than the fact that they exist," Vences says. Still, he guesses, their astounding inconspicuousness has likely played a role. They spend much of their time on the ground, often hiding under leaves. At night, they climb up to low-hanging branches to sleep. Furthermore, they would seem to have no direct predators. "Island formations like this are often weak in competition," Vences says.

The habitats of the other newly discovered chameleon varieties on mainland Madagascar are similarly small. "They are particularly threatened by habitat destruction," says co-author Köhler. "One of the new species, Brookesia desperata, is only known to inhabit a small rain forest, the interior of which is logged despite its being under official protection."

With its almost 300 frog varieties and 400 different reptiles, the fauna of Madagascar is considered unique. And new species are found on the island nation with astounding regularity. At the same time, however, many of them are extremely endangered, with the International Union for the Conservation of Nature estimating that some 40 percent of the reptile species in Madagascar are threatened, acutely threatened or in danger of extinction.

Adding to the problem is the unstable political situation in the country. An interim government has been in power since 2009 following a violent takeover. According to Germany's Foreign Ministry, a return to political and economic stability is not in sight. Habitat protection in such conditions is extremely challenging.

The researchers fear that a further, newly discovered species, Brookesia tristis, may likewise have an uncertain future. The chameleon's habitat was placed under protection several years ago, but since then logging has only increased.

Indeed, even the names the researchers chose for the new species are meant to highlight the great danger facing them. Desperate and sad, such may be their future.
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