SCIENCE LAB SPECIAL : APEX PREDATORS

 

The Vanished Saber Tooth : Bones disclose the long-held secret of apex predators' hidden pain.

Some 50,000 to 10,000 years ago, as ice sheet melted and the planet warmed, 100 species of gigantic animals started to disappear.

Among them were predators like the saber-tooth cat and the dire wolf.

Paleontologists have sought to understand why these animals died off. Hypotheses have included stiff competition for food, competition aggravated by the arrivals of humans and gray wolves.

But new evidence of a bone disease that can debilitate modern cats and dogs complicates the picture.

IN A NEW PAPER, researchers report that as the climate changed, the bones of saber-tooth cats and dire wolves became riddled with defects associated  with osteochondritis dissecans, or OCD, a disease in which holes form in developing bones.

In a live animal, it can lead to painful inflammation.

These findings are a fossilized snapshot of how the physiologies of prominent Pleistocene epoch predators most likely faltered under environmental pressures, said Mairin Balisi, curator of the Raymond M. Alf Museum of Paleontology in Claremont, Calif, and an author of the paper.

Ms.Balisi was part of a team that examined hundreds of fossils and found evidence of the condition in a significant number of young animals.  

It's possible they often outgrew the condition, but its prevalence suggested to researchers the likelihood in breeding among dwindling, isolated  populations of animals. [Miriam Fauzia]