A Bold Insight: Fossilized Bee Nests Carved into Bones Reveal a Side of Bee Life You Might Never Have Seen
Scientists exploring a Caribbean island cave have uncovered something completely new: ancient bees that behave very differently from the hive-dwelling insects we’re familiar with today.
For the first time, paleontologists have found fossil traces of burrowing bees nesting inside the buried bones of other animals. These fossils, dating back thousands of years, tell the story of a deadly, unusual life cycle that involved ancient rodents and giant barn owls. The discovery may also shed light on how bees operate today, according to the researchers.
“I think the most important takeaway is showing how diverse bee nesting behavior can be,” study researcher Lazaro Viñola Lopez told Gizmodo.
A chance find
Viñola Lopez was a doctoral student at the Florida Museum of Natural History when he helped excavate the fossils from inside Cueva de Mono, a cave on Hispaniola’s eastern coast, within the Dominican Republic. Neither he nor his team were expecting to find insects, since such creatures rarely preserve well in that environment.
The cave yielded thousands of fossils from hutia—rodent relatives of the guinea pig. That in itself was remarkable because hutia fossils are uncommon in the area. Yet one hutia mandible stood out for its unusually smooth surface, prompting closer examination.
Initially, Viñola Lopez contemplated that wasps might have used hutia remains to build nests, a possibility informed by his prior work with dinosaur fossils. However, the features didn’t match any known wasp nests, so he continued probing.
Eventually, the evidence pointed to a different insect: an ancient burrowing bee named Osnidum almontei, which nested inside the bones of other animals thousands of years ago. Further expeditions into the cave uncovered additional nesting traces inside a hutia vertebra and the pulp cavity of a sloth tooth (sloths once inhabited the Caribbean but were largely wiped out by human activity).
The team published their findings in the Proceedings of the Royal Society B Biological Sciences on Tuesday.
Unusual bees
We tend to picture bees as social creatures building large, visible hives. Yet most bee species are solitary and use a wide variety of nesting sites and materials. The ancient bees described here resemble modern bees in some ways, but they also exhibit striking differences.
“The bees that created these traces nested in the ground, much like some modern species, but they stand apart from all known bees because they regularly used cavities in buried bones—such as tooth sockets—for nesting,” Viñola Lopez explained. A key distinction is the cave setting itself. There’s only one other documented case of burrowing bees using a cave for nests, and that instance did not involve nesting inside another animal’s fossil remains.
What the researchers can tell us about the cave ecosystem is equally fascinating. The site appears to have housed a population of ancient barn owls that hunted hutias and may have used the cave as a dumping ground for their prey. The remains—whether eaten at the site or carried back to roosting spots—likely provided the bees with ready-made nesting chambers. In the surrounding landscape, suitable soil and microhabitats were limited, so the cave likely offered a rare, favorable environment for these bees.
This study not only broadens our understanding of bee diversity but also prompts scientists to rethink how they handle fossil deposits. Viñola Lopez notes that their methods have become more cautious: before cleaning fossils, researchers now check for delicate traces of ancient insect behavior that might be hidden within the sediment.
The researchers aren’t done yet. They’re continuing to describe the other fossils recovered from the cave, which may include previously unknown species of mammals, reptiles, and birds.
Would you expect bees to nest inside animal remains, or does this idea feel like science fiction? As scientists uncover more about these ancient insects, they may spark new debates about how adaptable bees can be—and what that could mean for understanding modern bee behavior and conservation.
