Raja raja cholan, King

New York, Nov 26 Fossils of a tiny sea creature that died more than half a billion years ago may compel a science textbook rewrite of how brains evolved.A study published in Science has revealed a 525-million-year-old fossil of a tiny sea creature with a delicately preserved nervous system, solving a century-old debate over how the brain evolved in arthropods, the most species-rich group in the animal kingdom."To our knowledge, this is the oldest fossilised brain we know of, so far," said Nicholas Strausfeld, a Regents Professor in the University of Arizona's Department of Neuroscience.Strausfeld and Frank Hirth, a reader of evolutionary neuroscience at King's College London, provide the first detailed description of Cardiodictyon catenulum, a wormlike animal preserved in rocks in China's southern Yunnan province.Measuring barely half an inch (less than 1.5 centimetres) long and initially discovered in 1984, the fossil had hidden a crucial secret until now: a delicately preserved nervous system, including a brain.Cardiodictyon belonged to an extinct group of animals known as armoured lobopod, which were abundant early during a period known as the Cambrian, when virtually all major animal lineages appeared over an extremely short time between 540 million and 500 million years ago.Lobopod likely moved about on the sea floor using multiple pairs of soft, stubby legs that lacked the joints of their descendants, the euarthropods - Greek for "real jointed foot."Today's closest living relatives of lobopod are velvet worms that live mainly in Australia, New Zealand and South America."This anatomy was completely unexpected because the heads and brains of modern arthropods, and some of their fossilised ancestors, have for over a hundred years been considered as segmented," Strausfeld said."From the 1880s, biologists noted the clearly segmented appearance of the trunk typical for arthropods, and basically extrapolated that to the head," Hirth said. "That is how the field arrived at supposing the head is an anterior extension of a segmented trunk.""But Cardiodictyon shows that the early head wasn't segmented, nor was its brain, which suggests the brain and the trunk nervous system likely evolved separately," Strausfeld noted.The findings also offer a message of continuity at a time when the planet is changing dramatically under the influence of climatic shifts."At a time when major geological and climatic events were reshaping the planet, simple marine animals such as Cardiodictyon gave rise to the world's most diverse group of organisms - the euarthropods a" that eventually spread to every emergent habitat on Earth, but which are now being threatened by our own ephemeral species," said the researchers.Disclaimer: This post has been auto-published from an agency feed without any modifications to the text and has not been reviewed by an editor

Raja Raja CholanFOLLOW

Raja raja cholan, Latest News

Bhutan's Education and Skills Development Ministry conducted an online national coding competition for students who had taken various CodeMonkey ... ...

Beth Mooney got her batting back on track thanks to a mammoth century partnership with Alyssa Healy that steered ... ...

Is there a logical method for you to decide whether to receive treatment or not after receiving a prostate ... ...

Indian Sailor Anandi Nandan Chandavarkar has won Gold at Asia's most prestigious 34th King's Cup Regatta 2022 in the ... ...

Noted American author Stephen King has once again called out Twitter CEO Elon Musk by taking a jab at ... ...

San Francisco, Nov 27 Twitter boss Elon Musk has said that the microblogging platform may exceed one billion ... ...

A rethink of how brains originated in science textbooks may be required in light of the fossils of a ... ...

New York, Nov 26 Fossils of a tiny sea creature that died more than half a billion years ... ...