[Carribean sponges - bulk isotopes] - Bulk isotope data from sponges collected in Summerland Key in Florida between July 27 - August 19, 2021 (Collaborative Research: Investigations into microbially mediated ecological diversification in sponges)

For example, variation in the abundance, diversity, and community composition of microbiomes across host species may drive niche partitioning due to differential assimilation and recycling of nutrients across sponge species. Stable isotope analysis of bulk sponge tissue allowed us to test for evidence of partitioning of three major resource pools (dissolved organic matter: DOM, particulate organic matter: POM, and inorganic nutrients: NaHCO3 and NaNO3) among four emergent Caribbean sponge species.

Results from bulk (holobiont tissue including both sponge and microbial cells) stable isotope analysis show niche partitioning, with strong interspecific variation in the relative exploitation of each resource pool. These results demonstrate that associations with microbial symbionts have facilitated niche partitioning by allowing host sponges to acquire and recycle diverse nutrient pools via unique mechanisms.