New Species Thread

Brazil finds prehistoric "Sea Warrior" crocodile

Wed Mar 26, 5:08 PM EDT

A fossil of a new marine crocodile species found in Brazil shows the reptiles survived the extinction of dinosaurs 65 million years ago, researchers said on Wednesday.

Brazilian paleontologists said the discovery of the fossil of Guarinisuchus munizi, dubbed "Sea Warrior," also engendered a new theory on the migration of prehistoric crocodiles from Africa to South and then North America.

The 62-million-year-old fossil, described in the London-based Proceedings of Royal Society B research journal, is part of the Dyrosauridae group, which replaced mosasaurs, or serpentine marine lizards, as the dominant marine predators in the Paleocene epoch.

"Based on the discovery, we know that's what happened near the Brazilian coast. Now the question is whether the same happened worldwide. We believe it did," said Alexander Kellner of the National Museum in Rio de Janeiro.

Guarinisuchus is derived from the word "warrior" in Brazil's Tupi Indian language. Munizi is a tribute to Brazilian paleontologist Geraldo da Costa Barro Muniz.

With the skull, jaw and vertebrae, the fossil is the most complete of its group found in South America.

"One of the reasons we called it a warrior is because it survived the phenomenon that made dinosaurs extinct ... And they were the dominant predators even though this one was relatively small, at 3 meters in length. But we know the size isn't always important, just take the piranha fish," Kellner told Reuters.

The fossil was found in the coastal Mina Poty area in northeastern Brazil.

(Reporting by Andrei Khalip; editing by Angus MacSwan and Philip Barbara)

(c) Reuters 2008.

In order for new species to thrive, they need to evolve to occupy their own niche in the ecosystem, relying on certain foods and habitats for survival that are sufficiently different from those of other closely related species.

Competition between closely related species for food and habitat becomes more intense the more species there are, and researchers believe this could be the reason for the drop-off in the appearance of new species over time.

Dr. Albert Phillimore, from Imperial College London's NERC Centre for Population Biology, lead author on the paper, explains: "The number of niches in any given region is finite, and our research supports the idea that the rate of speciation slows down as the number of niches begins to run out.

"In essence, it seems like increased competition between species could place limits on the number of species that evolve."

The new study used detailed analysis of the family trees, or phylogenies, of 45 different bird families. By examining the rate at which new species have arisen in each of these trees over a period of millions of years, scientists saw that the rate of appearance of new species seemed to be much higher in the early stages of the family tree, compared to more recent lower rates.

For example, when the researchers examined the phylogeny of tit birds they found that some 10 million years ago, species formed rapidly but this rate has slowed over time to perhaps a quarter of the initial rate.

The Caspian/Persian Tiger was used in Roman gladiatorial games. The fight was not even, the tiger became blinded when it was released into the coliseum, the sudden burst of light decided the battle.

And many of the beasts died before they ever set their foot in the arena. The majority of the animal care takers did not know how much to feed the animal, what to feed it, how to keep it in captivity etc.

World's smallest snake is as thin as spaghetti

Handout photo of Leptotyphlops carlae resting on US quarter

By Will Dunham, Reuters
Sun Aug 3, 9:07 AM EDT

Scientists have identified the world's smallest snake -- a reptile about 4 inches long and as thin as spaghetti that was found lurking under a rock on the Caribbean island of Barbados.

The new species, named Leptotyphlops carlae, is smaller than any of the other 3,100 previously known snake species, according to Pennsylvania State University biologist Blair Hedges, who also had helped find the world's smallest frog and lizard.

It is one of about 300 different species of threadsnake and is a dark brownish gray with two yellow stripes, Hedges said. It was determined to be a newly identified species due to genetic differences from other snakes and its unique color pattern and scales, he said.

The snake, which is not venomous, eats termites and termite larvae but little is known about its behavior, including whether it is nocturnal, Hedges said. It was found in 2006 in a forest on the eastern side of Barbados.

"It was under a rock. We got two of them," Hedges said in a phone interview. "It's about as wide as a spaghetti noodle."

The snake is about 0.2 inches (5 mm) shorter than another species from the Caribbean island of Martinique.

"When you get down that small, every millimeter counts," said Hedges, whose findings were published in the scientific journal Zootaxa on Sunday.

The biggest and smallest types of animals often are found living on islands where species over time can fill ecological niches in habitats without competition from other creatures not living in the isolated locations.

The world's longest snake is the reticulated python, which grows to 33 feet long and lives in Southeast Asia.

Snakes have lived since the time of the dinosaurs. The oldest known fossil snakes date from around 100 million years ago. The first snakes -- thought to have evolved from lizards -- actually had very small limbs.

Hedges thinks the new one may be at or near the minimum possible size for snakes. It lays a single slender egg that takes up a major part of the mother snake's body, he said.

(Editing by Julie Steenhuysen and Mohammad Zargham)

(c) Reuters 2008. All rights reserved.