Blind snakes on Madagascar arose when it broke up with India 100 mln yrs ago

Washington, March 31 (ANI): In a new research, a team of scientists discovered that blindsnakes are one of the few groups of organisms that inhabited Madagascar when it broke from India about 100 million years ago and are still living today.

The co-leaders of the team were Blair Hedges, professor of biology at Penn State University, US, and Nicolas Vidal, of the Museum National d”Histoire Naturelle in Paris.

Blindsnakes comprise about 260 different species and form the largest group of the world”s worm-like snakes – scolecophidians.

These burrowing animals typically are found in southern continents and tropical islands, but occur on all continents except Antarctica.

They have reduced vision – which is why they are called “blind” – and they feed on social insects including termites and ants.

Because there are almost no known fossil blindsnakes, their evolution has been difficult to piece together.

Also, because of their underground lifestyle, scientists have long wondered how they managed to spread from continent to continent.

In this study, the team investigated the evolution of blindsnakes by examining the genetics of living species.

They extracted five nuclear genes, which code for proteins, from 96 different species of worm-like snakes to reconstruct the branching pattern of their evolution and allow the team to estimate the times of divergence of different lineages within blindsnakes using molecular clocks.

“Our findings show that continental drift had a huge impact on blindsnake evolution by separating populations from each other as continents moved apart,” explained Vidal.

Mutations in the genes record the history of these blurry-eyed serpents.

The genetic research reveals that the original stock of worm-like snakes arose on Gondwana, the ancient southern supercontinent.

The initial split occurred about 155 million years ago as Gondwana divided into East Gondwana (the landmasses of Antarctica, India, Madagascar, and Australia) and West Gondwana (the landmasses of South America and Africa).

The residents of East Gondwana – the blindsnakes – then diverged into several lineages including a new family named in this study and found only on Madagascar.

Later, East Gondwana further divided into a new paleolandmass – called by the researchers “Indigascar” (India plus Madagascar) – and another comprised of Australia and Antarctica.

The research suggests that the new family on Madagascar arose as a result of the break-up of the Indigascar landmass about 94 million years ago.

Madagascar”s long isolation has led to the evolution of many unique endemic animals including this family of blindsnakes, various lemurs, and other rare mammals. (ANI)

First animals on Earth resembled blobs of gelatinous goo, reveal 850 mln yr old fossils

London, May 12 (ANI): Scientists have discovered 850 million year old fossil traces in Canadian rocks, which resembled blobs of gelatinous goo, that has potentially solved a major problem for the origin of animal life.

The previous oldest animal fossils date from “only” 650 million years ago, although “molecular clocks” based on rates of genetic divergence indicate that animals should have originated about 850 million years ago.

According to a report in New Scientist, the new findings may therefore help solve the problem of the 250 million-year-gap.

Palaeontologists have looked long and hard for traces left by the first multi-celled organisms, fully aware that the soft-bodies might have left very few fossils.

The breakthrough came when Elizabeth Turner, of Laurentian University in Sudbury, Ontario, spotted odd patterns in the rocks of 850-million-year-old limestone reefs in the Mackenzie Mountains of Canada’s Northwestern territory.

She has spent the last 15 years, with Fritz Neuweiler of University Laval in Quebec, trying to deduce their origin.

Now, Turner and Neuweiler, along with David Burdige of Old Dominion University in Virginia, have shown that the patterns match the distinctive textures found in reefs built by sponges.

Studies of modern sponges show that when their collagen structure decays it calcifies and leaves a signature pattern.

Since collagen is a fibrous protein found only in animals, some ancestral animal must have lived in the ancient reef, argue researchers.

The animal consisted of “cells living embedded in a scaffold of collagen, which they extruded to make their home,” said Turner.

“There probably were more than one type of cell, but we can’t tell. Nothing like it lives today, but if we saw one, it would look like a little blob of gelatinous goo,” she added.

The presence of animals this early in Earth’s history would resolve the long-standing disparity between molecular clocks and the fossil record, and show that the evolution of animals began before the Earth slipped twice into a global deep freeze.

“I applaud the approach of looking for distinctive textures seen along with sponge skeletons in younger rocks,” said Andrew Knoll of Harvard University. “It’s a good first step, but it’s not yet proof, he added. (ANI)