Sanoja Sridevan Rose Hills
Underground Sweat Bee Nest from the Late Cretaceous Gulf Coast
Angiosperms (flowering plants) are the most abundant type of plant on Earth. Their diversification and expansion during the Late Cretaceous greatly benefited insect pollinators, including bees. However, direct paleontological evidence of this important plant-pollinator interaction is scarce. This summer I will analyze an exceptionally preserved underground sweat bee nest (family Halictidae) from the Late Cretaceous Gulf coastal plain. I will perform and analyze micro-CT data to observe the nest morphology and contents in greater detail. Inside the nest, pollen pallets collected by the female bee to feed the developing larvae are also preserved. I will conduct Scanning Electron Microscopy to study the surface structures of the individual pollen grains to identify the plant group(s) that produced them. This palynological evidence, combined with associated leaf fossils from the same locality will provide a rare insight into the host plant usage by sweat bees during the angiosperm expansion. I hope to learn more about this significant plant-pollinator interaction during the large-scale transition that led to the diversity of flowering plants that exists today.