February 15, 2012
Mini Reptiles Discovered In Madagascar
Researchers have discovered four new species of miniature lizards in Madagascar, including one so small it can easily perch on the tip of your finger or on a match head, report scientists in the upcoming Wednesday issue of the open access journal PLoS ONE.
Brookesia micra, the tiniest chameleon ever discovered, grows to just about an inch (30 mm) long from nose to tail. All four species discovered belong to the genus Brookesia, known as leaf chameleons, which already contains some very small species, with members typically resembling juvenile versions of larger species.
Distinguishing each of the lizards as separate species was difficult because of their tiny size and similar appearances. The researchers used genetic analysis to determine they were in fact all separate species within the genus Brookesia.
Ted Townsend, of San Diego State University, who carried out the genetic testing, told Wil Longbottom of The Daily Mail Online: “Their size suggests that chameleons might have evolved in Madagascar from small and inconspicuous ancestors, quite unlike the larger and more colorful chameleons most familiar to us today.”
The new chameleon species are only found in an area just a few square miles in size. Half the members of this genus are found in only a single location and the tiniest of them -- B. micra -- lives only on the tiny island of Nosy Hara.
Experts say extreme miniaturization is common in island populations. Known as island dwarfism, it may occur due to limited resources and pressure to reproduce faster.
Frank Glaw, a herpetologist at the Zoological State Collection of Munich in Germany, and lead author of the study, told Adam Mann of Wired Science: “The extreme miniaturization of these dwarf reptiles might be accompanied by numerous specializations of the body plan, and this constitutes a promising field for future research.”
“But most urgent is to focus conservation efforts on these and other microendemic species in Madagascar which are heavily threatened by deforestation,” said Glaw.
The team searched for the tiny creatures at night, using headlamps and flashlights to track down the sleeping chameleons. The reptiles are active during the day, and at night climb “up into the branches” of trees, albeit just 4 inches off the ground, Glaw told Andrea Mustain of OurAmazingPlanet.
While the task of finding them was difficult, catching them was pretty easy, Glaw said. “They are sleeping and you can just pick them up. It´s like picking a strawberry, so it´s easy,” he remarked. “They do not move at all at night.”
The discoveries were made during expeditions to Madagascar´s wild northern regions between 2003 and 2007. The researchers said at least two of the chameleons are extremely threatened due to habitat loss and deforestation.
Glaw, who has been searching Madagascar´s wilds for more than 25 years, said these creatures may represent the limit of miniaturization possible for a vertebrae with complex eyes, but it is impossible to know for sure since each time scientists have proclaimed they have found the tiniest one yet, another tinier species is discovered.
“Maybe there's a potential for a smaller species,” said Glaw.
Glaw said he is planning another expedition to Madagascar in November. “I´m sure there are many surprises awaiting discovery,” he said.
Image Caption: A Brookesia micra standing on the head of a match. Credits: Frank Glaw, JÃ¶rn KÃ¶hler, Ted M. Townsend, Miguel Vences. PLoS ONE
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