Belgian Researchers Describe Ancestor of Lions, Dogs

Newly discovered fossils from Belgium have shown that the ancestor of the most-feared carnivore was a little animal that weighed about two pounds and lived on trees.

According to Floréal Solé, a researcher from the Royal Belgian Institute of Natural Sciences and colleagues, all the carnivores, right from ferocious lions and tigers to the cute dogs and cats trace their origins back to an animal that lived about 55 million years ago.

"It wasn't frightening. It wasn't dreadful," said Solé, who is also a paleontologist at the Royal Belgian Institute of Natural Sciences in Brussels, Livescience reported. The animal fed on small mammals and insects.

The species is called Dormaalocyon latouri. It was previously found at the Belgian locality of Dormaal, from where it gets its name. The new fossils studied by Solé and his colleagues shed light on the evolution of the animal along with its placement on the family-tree of modern carnivores.

Dormaalocyon lived about 55 million years ago- a time period called the Eocene. Other researchers have found that most of the ancestors of the modern mammals appeared during Eocene. All the animals living during this time were under 10 kilograms or 22 pounds.

The Tree Dweller

The old sample of the animal had just two upper molars while the latest specimen has an entire tooth row. In all, researchers found some 250 teeth and bones, which have helped them better describe Dormaalocyon.

Analysis of the fossil's ankle bones has shown that the animal was an arboreal, meaning that it lived on trees. The animal might have first lived in Europe.

Previous research has shown that about 55 million years ago, Dormaal was a warm, humid and thickly wooded area. During this time, earth was recovering from an event called the Paleocene-Eocene Thermal Maximum (or PETM)- a time when global temperatures increased rapidly, probably due to release of methane hydrates in the environment.

According to the researchers, Dormaalocyon might have thrived after the PETM event. The idea that the animal lived on trees and was capable of invading North America "supports the existence of a continuous evergreen forest belt at high latitudes during the PETM," Dr. Solé said in a news release.

Not the Oldest

Dormaalocyon is one of the ancestors of carnivores, but not the oldest one, researchers said. Some other primitive animals might have lived during an earlier time period- the Paleocene.

"The understanding of the origination of the carnivoraforms is important for reconstructing the adaptation of placental mammals to carnivorous diet. Therefore, Dormaalocyon provides information concerning the evolution of placental mammals after the disappearance of the largest dinosaurs (at the Cretaceous-Paleogene extinction event)," Solé said in a news release. "Our study shows that the carnivoraforms were very diversified at the earliest Eocene, which allows hypothesizing that they were probably already diversified during the latest Paleocene".

The study is published in the Journal of Vertebrate Paleontology.