Those who help each other can invade harsher environments

Date: February 20, 2017

Source: Lund University

Through cooperation, animals are able to colonize harsher living environments that would otherwise be inaccessible, according to a new study from Lund University in Sweden, together with researchers in England and USA. The research community has long believed this was the other way around -- that species in tough environments had to cooperate to survive. As a result the established view of why animals cooperate is turned upside-down.

Some species of birds cooperate closely in the rearing of offspring. The older siblings appear to selflessly help their parents rear the youngest brood. This phenomenon is most common in species that live in harsh environments, where the climate is hot and rain is scarce.

For a long time, researchers believed that the harsh conditions have forced individuals to help because they can't breed on their own. It seems, however, the opposite is true -- that the cooperation evolves first, and this gives species a chance of successfully invading and surviving in more barren places.

"Cooperation appears to be an important prerequisite to colonization of arid habitats," says Charlie Cornwallis, biologist at the Faculty of Science at Lund University.

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700,000-Year-Old Horse Found in Yukon Permafrost Yields Oldest DNA Ever Decoded

Posted on November 19, 2013 • Updated February 23, 2017 —by Blake de Pastino

The frozen remains of a horse more than half a million years old have reluctantly given up their genetic secrets, providing scientists with the oldest DNA ever sequenced. 

The horse was discovered in 2003 in the ancient permafrost of Canada’s west-central Yukon Territory, not far from the Alaskan border. 

And although the animal was dated to between 560,000 and 780,000 years old, an international team of researchers was able to use a new combination of techniques to decipher its genetic code. 

Among the team’s findings is that the genus Equus — which includes all horses, donkeys, and zebras — dates back more than 4 million years, twice as long ago as scientists had previously believed. 

“When we started the project, everyone — including us, to be honest — thought it was impossible,” said Dr. Ludovic Orlando of the University of Copenhagen, who coordinated the research, in a statement to Western Digs. 

“And it was to some extent, with the methods available by then. So it’s clearly methodological advances that made this possible.” 

Orlando and his colleagues published their findings this summer in the journal Nature; he discussed them today in a lecture at The Royal Society, London. 

Previous to this, the oldest genome ever sequenced was of a 120,000-year-old polar bear — no small feat considering that the half-life of a DNA molecule is estimated to be about 521 years. 

By this reckoning, even under the best conditions, DNA could remain intact for no more than 6.8 million years. 

But Orlando’s team was able to make the most of what they had for a number of reasons, he said. 

Continued  

Fossil of a beetle inside a lizard inside a snake – an ancient food chain – via Herp Digest

Feb 23, 2017, Vintage News

A unique fossil, demonstrating an ancient food chain was discovered by researchers studying the Messel pit on a dig site near Frankfurt, and it is believed to be 48 million years old.

The specimen contains a snake that died shortly after eating a lizard that had recently eaten a beetle.

It is impressive that such a fossil exists in such a well-preserved state, and that each consumed creature is recognizable. The snake was known to be a member of the species Palaeopython fischeri, which is an extinct type of snake once found in what is now Germany. It was a tree-dwelling snake related to modern boas. Growing to a size of up to 2 meters, they could live on the ground or in shallow water near riverbanks. The individual in this fossil, however, was only 103 centimeters in length and so is thought to be a juvenile.

The lizard belongs to the species Geiseltaliellus maarius. It is an extinct lizard of the iguanian lizards that are found in Germany, Belgium, and France. The best-preserved ones are found in the Messel pit in Germany. These lizards had long legs, short arms, and a long tail. The tail was adapted to running and climbing on the ground and in trees. The long toe bones of these lizards, like those of their living cousins, suggest that this species spent most of its time in trees. The probable paleoenvironment of the Messel Pit would have been a dense forest.

Paleoecology is the science of determining ancient environments. Using the evidence found in fossils, it reconstructs the ecosystems these creatures would have lived in. Traces left behind in the fossil record, such as seeds, shells, teeth, and pollen, help scientists infer characteristics of the environment. Therefore, a fossil field like the Messel pit in Germany offers valuable clues to not just the creatures themselves, but to what the plant life would have been like too.

Scientists can tell that the lizard is inside the snake due to the way the snake’s ribs overlap those of the lizard. The lizard had the ability to shed its tail when attacked but did not do so before being eaten, as its complete remains are intact inside the snake. The beetle is not preserved enough to be meaningfully identified.

Also discovered at the same site is the last meal of grapes and leaves inside a fossilized prehistoric horse. Pollen grains found inside fossilized bird and insect remains visible in fish excrement are a testament to the excellent preservation qualities of the area.

Previous fossils of reptiles contained only plant remains due to the speed of the creature’s digestive system. The Messel Pit will likely yield more fascinating finds as digs continue.