Nature & Environment

Carnivore Death Cave: Paleontologists Discover Remains of Ancient Animals in Underground Cavern

Staff Reporter
First Posted: May 03, 2013 08:51 AM EDT

A new study suggests that a cavern in Spain that created hopes of food and water may have lured ancient carnivores to their death.

Scientists hope this may explain how carcasses of several carnivorous species, including saber-toothed cats and "bear dogs," wound up in an underground cavern millions of years ago.

"Only the carnivores were daring enough to enter," said M. Soledad Domingo, a paleontologist at the University of Michigan and the study co-author. "But they were unable to make their way out."

Uncovered bones were discovered just 19 miles outside of Madrid by local miners who were drilling the area in 1991, who soon called in paleontologists to excavate. They uncovered a series of underground cavers full of animal fossils that included the remains of red pandas, bear dogs and saber-toothed cats. Ancient animals similar to modern elephants, giraffes, rhinoceroses and horses were also found, according to the study.

To date, nearly 18,000 fossils have been recovered from the area.

The so-called Cerro de los Batallones caves formed between 9 million and 10 million years ago in a process known as piping, where sediment falls into cracks or fissures in the surface, carving out hollow spaces in the soft, claylike Earth.

Researchers are uncertain as to what caused the death of the animals, but Domingo and colleagues analyzed their bones to discover the bottom level of the site.

The cave contained an unusually high proportion of carnivores, some of which were completely unknown before the cave's discovery, according to LiveScience.

The researchers found that nearly 98 percent of the large-mammal fossils were of carnivores, many of them healthy young adults. They also studied the orientation of the skeletons in the cave and the lack of trample marks.

Based on these findings, the team concluded that the cave probably had a visible opening in the ground, into which the herbivores may have occasionally fallen. However, most of the herbivores were smart enough to avoid the trap.

"We think that the carnivores were getting trapped, and then they became additional food for another coming carnivore," Domingo said.

However, researchers are still also uncertain as to how long the cave was open before flooding covered up the space. Thus, further studies need to be conducted in order to determine more information.

The findings for the study were published May 1 in the journal PLOS ONE

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