Tuesday, December 16, 2008

Shell game: How the turtle got its home

PARIS (AFP) – A stunningly intact 220-million-year-old fossil found in southwestern China appears to have settled a long-simmering debate over reptile evolution: how did turtles get their shell?
In a study to be published Thursday, scientists report on the discovery of a missing-link species -- Odontochelys semitestacea, for "toothed, half-shell turtle" -- whose outer shell emerged directly from the ribs and backbone and not from the skin, as some have argued.
The find also suggests that turtles originated in water rather than on land, and pushes back the group's first known appearance on Earth by some 10 million years.
Since the era of dinosaurs, which roamed the planet until 65 million years ago, turtles have looked pretty much the way they do today.
They sport an armour-like upper shell, known as a carapace, connected to a softer lower part, called a plastron.

More than 1,000 species discovered in Mekong: WWF

BANGKOK (AFP) – Scientists have discovered more than 1,000 species in Southeast Asia's Greater Mekong region in the past decade, including a spider as big as a dinner plate, the World Wildlife Fund said Monday.
A rat thought to have become extinct 11 million years ago and a cyanide-laced, shocking pink millipede were among creatures found in what the group called a "biological treasure trove".
The species were all found in the rainforests and wetlands along the Mekong River, which flows through Cambodia, Laos, Myanmar, Thailand, Vietnam and the southern Chinese province of Yunnan.
"It doesn't get any better than this," Stuart Chapman, director of WWF's Greater Mekong Programme, was quoted as saying in a statement by the group.
"We thought discoveries of this scale were confined to the history books."
The WWF report, "First Contact in the Greater Mekong", said that "between 1997 and 2007, at least 1,068 have been officially described by science as being newly discovered species."
These included the world's largest huntsman spider, with a leg span of 30 centimetres (11.8 inches), and the "startlingly" coloured "dragon millipede", which produces the deadly compound cyanide.