A Battle of the Vampires, 20 Million Years Ago?

ScienceDaily (Feb. 3, 2012) — They are tiny, ugly, disease-carrying little blood-suckers that most people have never seen or heard of, but a new discovery in a one-of-a-kind fossil shows that "bat flies" have been doing their noxious business with bats for at least 20 million years.

For bats, that's a long time to deal with a parasite doing its best vampire impression. Maybe it is nature's revenge on the vampire bat, an aggressive blood consumer in its own right that will feed on anything from sheep to dogs and humans.

The find was made by researchers from Oregon State University in amber from the Dominican Republic that was formed 20-30 million years ago. The bat fly was entombed and perfectly preserved for all that time in what was then oozing tree sap and later became a semi-precious stone.

This is the only fossil ever found of a bat fly, and scientists say it's an extraordinary discovery. It was also carrying malaria, further evidence of the long time that malaria has been prevalent in the New World. The genus of bat fly discovered in this research is now extinct.

The findings have been published in two professional journals, Systematic Parasitology and Parasites and Vectors.

"Bat flies are a remarkable case of specific evolution, animals that have co-evolved with bats and are found nowhere else," said George Poinar, Jr., an OSU professor of zoology and one of the world's leading experts on the study of ancient ecosystems through plants and animals preserved in amber.

"Bats are mammals that go back about 50 million years, the only true flying mammal, and the earliest species had claws and climbed trees," Poinar said. "We now know that bat flies have been parasitizing them for at least half that time, and they are found exclusively in their fur. They are somewhat flat-sided like a flea, allowing them to move more easily through bat fur."

Not every bat is infested with bat flies, and some of the contemporary flies are specific to certain species of bats. But they are still pretty common and found around the world.

Bat flies only leave their bat in order to mate, Poinar said, and that's probably what this specimen was doing when it got stuck in some sticky, oozing sap.

http://www.sciencedaily.com/releases/2012/02/120203102414.htm

Ancient Fungi-Plant Duo Discovered in Amber

A walnut-size piece of amber from 52-million years ago reveals what scientists say is the oldest, tight-knit partnership between a fungus and a tropical tree.

An international team of scientists from the United States, Germany and India discovered the rare fossil in the Tadkeshwar Lignite Mine of Gujarat State, western India.

Such symbiotic partnerships (which benefit both parties) as the one preserved inside amber, or plant resin, have made possible the survival of most land plants today, the researchers note. The fungi have threadlike cells that increase the surface area of the plant's roots, increasing the plant's access to necessary nutrients from the soil. In return, the fungus gets sugary foods that the plant produces. This fungus-plant root partnership is called a micorrhizal relationship.

"Mycorrhizal relationships are believed to have arisen more than 400-million years ago, as plants began to colonize terrestrial habitats," Paul Nascimbene, of the American Museum of Natural History's division of invertebrate zoology, said in a statement. "They are seen as a key innovation in the evolution of vascular plants."


Read more here ...

Polar bears traced back to Britain

All polar bears originate from a single ancestor which lived in Britain or Ireland about 50,000 years ago, according to DNA study by scientists. New evidence from fossils found in Irish caves shows that modern polar bars evolved from a single female brown bear at the peak of the last ice age.

Despite the significant differences between polar bears, which are expert swimmers, and brown bears, which are better climbers, the species have often come into contact over the past 100,000 years during periods of unusually hot or cold weather.

A genetic marker carried by every polar bear alive today proves that they all descend from the same female brown bear, who bred with a polar bear to create hybrid offspring.

It had been assumed that this took place in Alaska 14,000 years ago, but now analysis of 242 brown bear and polar bear DNA samples from the past 120,000 years show the hybridisation of the two species occurred much earlier.

Fossils found in Irish caves show that polar bears in fact began carrying the DNA of the female brown bear between 20,000 and 50,000 years ago, before brown bears disappeared from the British Isles.

The study, led by Dr Beth Shapiro of Penn State University in the USA and Prof Daniel Bradley of Trinity College Dublin, was published in the journal Current Biology.

Dr Shapiro said: “Previous research has indicated that the brown bear contributed genetic material to the polar bear's mitochondrial lineage – the DNA that is passed exclusively from mothers to offspring.

“But, until now, it was unclear just when modern polar bears acquired their mitochondrial genome in its present form."

By Nick Collins, Science Correspondent
http://www.telegraph.co.uk/earth/wildlife/8622987/Polar-bears-traced-back-to-Britain.html

Crocs dispel 'living fossil' myth

Crocodiles can no longer be referred to as "living fossils", according to scientists.


Members of the crocodilian family have previously been thought to have changed little since prehistoric times.

However, new fossil analyses suggests that modern crocodilians actually evolved from a very diverse group.

Recently discovered ancient ancestors include small cat-like specimens, giant "supercrocs" and a pug-nosed vegetarian species.

Body structure
Modern crocodilians are adapted to aquatic environments with long snouts, strong tails and powerful jaws.

Yet contrary to popular belief, scientists now suggest that the basic body structure of crocodiles, alligators and ghariels evolved from a diverse group of prehistoric reptiles with different body shapes.

Since first discovering the unusual crocodilian Simosuchus clarki ten years ago, palaeontologists have worked to recover its fossil from Madagascar.


A decade later, a near-complete skeleton has been achieved, and its analysis has reignited discussion on the evolution of modern crocodilians.

"The skull and lower jaw in particular are preserved almost completely," says Nathan J. Kley, co-editor of the recent study in the Society of Vertebrate Paleontology Memoir.

"This, combined with high-resolution CT scans of the most exquisitely preserved specimen, has allowed us to describe the structure of the head skeleton - both externally and internally - in exceptional detail, including even the pathways of the tiniest nerves and blood vessels," he says.

Tank-like
S. clarki differs greatly to other crocodilians with a blunt snout, short tail and "tank-like" body.

With its short jaw and weak, leaf-shaped teeth, scientists suggest that the reptile would have been unable to take prey from the water's edge in the same way modern crocodiles do.


Instead, researchers propose that the ancient crocodile lived inland, feeding on vegetation in its semi-arid grassland habitat.

Researchers describe S. clarki as the "most bizarre" of a group of fossilised crocodilians thought to live around 66 million years ago.

This year, palaeontologists working in Tanzania also unearthed fossils of a tiny crocodile-like creature with teeth resembling those of mammals.

The "cat-like" crocodilian's unusual teeth differ from the conical teeth of modern crocodiles, used for ripping and tearing.

At the larger end of the scale, the preserved remains of an eight-tonne giant crocodile further fuelled debate when they were recovered in 2001.

By Ella Davies

Earth News reporter

Crocs dispel 'living fossil' myth

Crocodiles can no longer be referred to as "living fossils", according to scientists.


Members of the crocodilian family have previously been thought to have changed little since prehistoric times.

However, new fossil analyses suggests that modern crocodilians actually evolved from a very diverse group.

Recently discovered ancient ancestors include small cat-like specimens, giant "supercrocs" and a pug-nosed vegetarian species.

Body structure
Modern crocodilians are adapted to aquatic environments with long snouts, strong tails and powerful jaws.

Yet contrary to popular belief, scientists now suggest that the basic body structure of crocodiles, alligators and ghariels evolved from a diverse group of prehistoric reptiles with different body shapes.

Since first discovering the unusual crocodilian Simosuchus clarki ten years ago, palaeontologists have worked to recover its fossil from Madagascar.


A decade later, a near-complete skeleton has been achieved, and its analysis has reignited discussion on the evolution of modern crocodilians.

"The skull and lower jaw in particular are preserved almost completely," says Nathan J. Kley, co-editor of the recent study in the Society of Vertebrate Paleontology Memoir.

"This, combined with high-resolution CT scans of the most exquisitely preserved specimen, has allowed us to describe the structure of the head skeleton - both externally and internally - in exceptional detail, including even the pathways of the tiniest nerves and blood vessels," he says.

Tank-like
S. clarki differs greatly to other crocodilians with a blunt snout, short tail and "tank-like" body.

With its short jaw and weak, leaf-shaped teeth, scientists suggest that the reptile would have been unable to take prey from the water's edge in the same way modern crocodiles do.


Instead, researchers propose that the ancient crocodile lived inland, feeding on vegetation in its semi-arid grassland habitat.

Researchers describe S. clarki as the "most bizarre" of a group of fossilised crocodilians thought to live around 66 million years ago.

This year, palaeontologists working in Tanzania also unearthed fossils of a tiny crocodile-like creature with teeth resembling those of mammals.

The "cat-like" crocodilian's unusual teeth differ from the conical teeth of modern crocodiles, used for ripping and tearing.

At the larger end of the scale, the preserved remains of an eight-tonne giant crocodile further fuelled debate when they were recovered in 2001.

By Ella Davies

Earth News reporter