Science Daily has a post about a recent paper that looked at novel bee nesting behavior. Researchers working on the Caribbean island of Hispaniola discovered a rare and unusual fossil interaction in a cave, ancient bees used fossilized bones as nesting sites.

Thousands of years ago, large barn owls brought their prey, in this case, hutias, a type of rodent, into a cave. The rodent’s bones accumulated and over time became partially fossilized in fine sediment. Later, burrowing bees exploited this environment, digging into the soft cave deposits and even using natural cavities in bones, such as tooth sockets as ready-made nests. The bees lined these cavities with a waterproof coating, which preserved them.

This research was published in the paper “Trace fossils within mammal remains reveal novel bee nesting behaviour” in the journal Royal Society Open Science.

Note: the lead author, Lázaro W. Viñola-López, is now at the Field Museum in Chicago.

The discovery might have been missed if not for careful attention during excavation.

“Usually, when collecting fossils, you get all the sediment out of the alveoli while cleaning the specimen,” said Lazaro Viñola Lopez, who excavated the fossils while working as a doctoral student at the Florida Museum of Natural History.

Viñola Lopez was particularly interested in this species of hutia, which was rarely found elsewhere on the island. In the Cueva de Mono in the southern Dominican Republic, he uncovered thousands of fossils from what appeared to be the same species. The cave had likely served as a long-term feeding site for giant barn owls, which repeatedly brought prey back to the same location over many generations.

Rather than immediately cleaning the fossils, he inspected them closely. One cavity stood out because its inner surface was smooth instead of rough like bone.

“I’d seen something similar in Montana when I was collecting dinosaur fossils in 2014,” he said. At the time, he and his colleagues found wasp cocoons mixed in with fossil material. He initially assumed the same explanation applied here. He recalls thinking, “it would be nice to write a short paper reporting the occurrence of these wasp nests in the mandibles.”