Image Gallery: Carnivore Death Cave

Deadly lure

sabertooth cats circle a rhinoceros carcass in a cave — (Image credit: MAURICIO ANTÓN)

Ancient history near the city

A view of Madrid from up high — (Image credit: Davidht | Flickr.com)

In 1991, miners about 30 kilometers (18.7 miles) from Madrid in Spain noticed a trove of bones at their digging site. They alerted paleontologists, who began excavating. To date, paleontologists have unearthed 18,000 fossils from 9 to 10 million years ago.

Doomed predator

a sabertooth cat skull from batallones — (Image credit: M. Soledad Domingo)

At the bottom of the site, in an area called Batallones-1, they found carnivore skeletons from many different ancient animals, including the now-extinct sabertooth cat. Many of the skeletons were unusually well-preserved.

Hyena skeleton

the skeleton of a hyena in a cave in Batallones in Spain — (Image credit: Domingo MS, Alberdi MT, Azanza B, Silva PG, Morales J (2013) Origin of an Assemblage Massively Dominated by Carnivorans from the Miocene of Spain. PLoS ONE 8(5): e63046. doi:10.1371/journal.pone.0063046)

The researchers carefully analyzed the type, age, and orientation of fossils, such as this hyena skeleton, to figure out what happened.

Bear-dog

Because 98 percent of the fossils came from carnivores, and most of those from healthy young adults, the researchers concluded that the carnivores willingly entered the cave in search of food or water. While the occasional herbivore may have fallen in by accident, only the carnivores were daring enough to enter the cave willingly. Once there, however, they were trapped and died.

Cave history

An illustration of the processes that occurred at the killer cave over time — (Image credit: MAURICIO ANTÓN, ISRAEL M. SÁNCHEZ and M. SOLEDAD DOMINGO.)

The researchers reconstructed the history of the cave. Sediments from the surface fell through fissures in the Earth and formed the cave. Young predators were lured in by the promise of food or water, but became trapped. The smell of their rotting carcasses would then attract other predators. Over time, the cave was filled in by flooding, until it became hidden from view.

Tia is the editor-in-chief (premium) and was formerly managing editor and senior writer for Live Science. Her work has appeared in Scientific American, Wired.com, Science News and other outlets. She holds a master's degree in bioengineering from the University of Washington, a graduate certificate in science writing from UC Santa Cruz and a bachelor's degree in mechanical engineering from the University of Texas at Austin. Tia was part of a team at the Milwaukee Journal Sentinel that published the Empty Cradles series on preterm births, which won multiple awards, including the 2012 Casey Medal for Meritorious Journalism.