August 20, 2013

The first new species of mammal identified in the Western Hemisphere in 35 years has been unveiled by a scientist who spent 10 years trying to prove that a specimen he found in a museum drawer was, in fact, a new kind of raccoon. The new animal, which has reddish-orange fur and a bushy tail, is called a olinguito, a Spanish word meaning little, adorable olingo. Olingos are members of the raccoon family, with brownish fur and larger bodies and ears than the olinguito. At only 2 pounds (0.9 kilogram), the olinguito is the smallest raccoon known to scientists. Kristofer Helgen of the Smithsonian Institution in Washington, D.C., led the team that found the olinguito in the cloud forests of the Andes Mountains in Ecuador and Columbia.

The olinguito of Central and South America is the first canivore discovered in the New World in 35 years. (Mark Gurney)

Although new to science, the olinguito is not new to scientists. That is, scientists had previously observed the animal in the wild, collected pelts for museum collections, and even displayed the animal in zoos. But they never realized that it was a separate species. Helgen first saw the olinguito in the specimen collection at the Field Museum in Chicago while working to count the number of olingo species. After spending some years trying to prove that the specimen represented a new kind of raccoon, Helgen and other scientists traveled to the Andes to search for the animal in its natural habitat. Further studies, including genetic testing, confirmed that the animal was a previously unknown species.

The olinguito, whose scientific name is Bassaricyon neblina, is about the size of a hamster. Because of its well-developed canine teeth, the olinguito is considered a carnivore. Most carnivores are meat-eaters. However, like other members of the raccoon family, the olinguito eats other foods, particularly figs, insects, and plant nectar. Although tens of thousands of olinguitos live in the northern Andes, the people of the region apparently have never named it.

Additional World Book articles:

• Coati
• Ringtail

May 15, 2012

Scientists studying the fossil of a monstrous ocean-dwelling reptile that lived about 150 million years ago found evidence that the fearsome carnivore was even tougher than they had imagined. The reptile, a female pliosaur, had apparently survived into old age even though its massive jaw had been seriously weakened by a condition similar to arthritis. Until this finding by researchers at the University of Bristol in the United Kingdom, scientists had not known that pliosaurs could develop a degenerative disease that is often linked to the aging process.

Pliosaurs were a type of plesiosaur, a now-extinct marine reptile that lived in the Mesozoic Era, from about 200 million to 65 million years ago. Pliosaurs, which were not dinosaurs, had large crocodile-like heads, short necks, and stiff whale-like bodies. The Bristol pliosaur was 26 feet (8 meters) long, with a 10-foot- (3-meter-) long head containing 8-inch- (20-centimeter-) long teeth. Paleontologist Michael Benton noted that a person could have lain down in the reptile’s huge mouth. Equipped with two pairs of flippers, pliosaurs were fast, powerful swimmers. Pliosaurs, which probably fed on large fish and other ocean reptiles, were the top predators (highest predators on the food chain) in the ocean for millions of years. Plesiosaurs evolved (developed gradually) from reptile ancestors that lived on land. Like modern whales, plesiosaurs had to surface to breathe air, and they likely gave birth to live young.

Pliosaurs were a kind of plesiosaur (above), a large ocean reptile that lived from about 200 million to 65 million years ago, during the time of the dinosaurs. Like plesiosaurs, pliosaurs had a round, stiff trunk and a tail. They had two pairs of flippers instead of arms and legs. (World Book illustration by Jay Bensen, Studio 3 Creative Associates)

The arthritis-like disease, which was likely painful, had caused the pliosaur’s left jaw to shift to one side. Tooth marks from the upper jaw in the bone of the lower jaw indicated that the pliosaur had survived for a numer of years even with a crooked jaw. The scientists also found that a tooth from the lower jaw had apparently caused an infection in a tooth socket of the upper jaw. At some point, the jaw had become so weak that it broke and the animal was unable to hunt. The pliosaur’s large size and fused skull bones suggested that it was old when it died.

Additional World Book articles:

• Prehistoric animal
• Reptile (The evolution of reptiles)