This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2025. The fellowship supports research and training of the fellow that will contribute to biology in innovative ways. This project will study how cnidarians and algae form specific partnerships. Many cnidarians form a symbiotic relationship with algae, which provide essential nutrients to the host. This partnership is critical for corals, the cnidarians which build coral reefs. Coral reefs are important for the environment and the economy, but the relationship between corals and algae is vulnerable to changes in the environment. One way that corals can survive stressful conditions is by partnering with resistant algae. However, there are limits to which algae can associate with which corals. This research will study the chemical, molecular, and cellular processes that happen when these relationships form, which is important for understanding symbiosis and conserving corals. The fellow will work with a team of scientists and teachers to accomplish research and educational goals. Additionally, the fellow will collaborate with artists to raise public awareness about coral reefs through a dance performance. Partner specificity is often conferred by multi-step ‘winnowing’ mechanisms which select for compatible symbionts out of a diverse microbial pool. In cnidarian-algal symbioses, symbionts are initially taken up through phagocytosis, the same mechanism which initiates feeding and pathogen elimination