A recent discovery in a limestone cave on the Caribbean island of Hispaniola has revealed the existence of ancient bee nests built inside the tooth sockets of fossilized animal bones. This unprecedented finding, which marks the first recorded instance of bees using bones for nesting, was detailed in a study published on October 3, 2023, in the journal Royal Society Open Science.
The research, led by Lázaro Viñola-López, a postdoctoral researcher at the Field Museum of Natural History in Chicago, challenges conventional perceptions of bee nesting behavior. Generally, it is understood that about 90% of bee species are solitary and build their nests underground or within decaying wood. The discovery of these nests within a cave setting offers new insights into the adaptability and diversity of bee nesting strategies, particularly in the context of ancient ecosystems.
Viñola-López and his team were exploring the cave in the summer of 2022 while conducting research for his doctoral program at the Florida Museum of Natural History. The cave, known for its rich deposits of fossils from over 50 species, contained remnants of animals such as rodents and birds. According to the study, the cave likely served as a long-term habitat for barn owls, which may have coughed up prey bones that eventually fossilized.
Upon examining the fossilized bones, Viñola-López noticed dirt lining the insides of the tooth sockets, reminiscent of the nesting habits of wasps. However, through CT scans, the researchers confirmed that the nests were constructed from mud, indicative of bee nesting behavior. The researchers determined that these nests date back approximately 20,000 years, significantly younger than other known bee fossils in the Caribbean, which are found in amber and are around 20 million years old.
“There is very little known about the ecology of many of the bees on these islands,” Viñola-López stated. “This shows that the diversity of nesting processes of bees is actually really big and sometimes expands past what we think is normal.” His observations underline the necessity for paleontologists to examine specimens closely for potential hidden biodiversity.
The cave environment provided ideal conditions for the preservation of these nests, which were likely protected from external weather influences. The findings suggest that the humidity within the cave may have facilitated nesting behavior, offering bees refuge from predators and harsh conditions.
While the specific species of the nesting bees remains unidentified, the nests have been named Osnidum almontei in honor of Juan Almonte Milan, the scientist who first discovered the cave. The research team noted that the nests contain evidence of multiple generations of bees returning to the same site, indicating a form of communal nesting.
This remarkable discovery adds to the understanding of ancient bee behavior. Anthony Martin, a professor of practice in the environmental sciences department at Emory University, commented on the significance of the findings, stating, “This discovery is doubly surprising because modern bees aren’t known to use bones for their nesting, nor are they known to nest in caves.”
As the research continues, Viñola-López expressed his desire to conduct further surveys in the area to determine if similar nesting behaviors are present among contemporary bee populations or in other cave environments. This study not only enhances our understanding of bee evolution but also serves as a reminder of the complexities of biodiversity and adaptation in ancient ecosystems.
The implications of this work extend beyond paleontology, offering insights into how modern bees might respond to environmental changes and challenges. As researchers delve deeper into the fossil record, new discoveries like these are likely to reshape established narratives about insect behavior and adaptation.
