Killer entrance suspected in mystery of unusually large group of carnivores in ancient cave

Different reasons have previously been offered to explain the unusually large concentration of healthy adult carnivores in this cave, including mass mortality, accidental falls into the cave, or simply that the animals died in other locations and were washed up into the cave. However, none of these could explain the absence of herbivores (nearly 98% of the fossils are of carnivores) or the large numbers of apparently healthy adults.

In the present study, authors examined the geological conditions under which the cave was formed, the age of individuals in the cave and the time frame over which they likely entered this pit. Tracking clues like the demography of the individuals recovered, the orientation of the remains and scarcity of fractured bones or trampling marks, among others, the researchers conclude that the animals most likely actively entered the cavity in search of food or water over a protracted period of time and were subsequently unable to make their way out, ultimately dying in the cave.

They suggest that the scarcity of herbivore remains may indicate that the cavity was clearly visible and thus avoided by these animals. Fossil bones in this site exhibit a very good preservation state as a consequence of their deposition in the restricted and protective environment of the chamber.