A team of researchers in the US have received grant funding from the National Science Foundation (US NSF) to study microbially mediated ecological diversification in sponges found in the Caribbean. Team member Dr. Cara Fiore explains:
“Coral reefs represent a paradox because, despite their immense productivity and biodiversity, they are found in nutrient-poor habitats that are equivalent to ‘marine deserts.’
“In part, the success of many coral reef organisms like sponges and corals, are a result of an association of the host sponge or coral with diverse symbiotic microbes that live on and within the host. These microbes help recycle nutrients for the host organism and can provide new nutrients to the host.”
[Fiore] said sponges are particularly abundant in the Caribbean, where their biomass exceeds that of reef-building corals. “Sponges are unique on coral reefs because they are efficient at filtering seawater for nutrients, can grow to a large size and they are prevalent on reefs worldwide,” Fiore said.
“For almost a quarter century, this success of sponge populations in the Caribbean has been linked to their filter-feeding ability; however, recent work has demonstrated that coexisting sponge species host unique communities of bacterial symbionts that might provide nutrients to each sponge host.”
“We will test the hypothesis that all sponge species in the Caribbean do not obtain nutrients in the same way, rather, they have unique nutritional strategies that are mediated by their microbial communities. This research will combine field experiments and modern analytical tools to investigate environmental and physiological factors that may have led to the diverse and abundant sponge populations observed in the Caribbean today.”
[Image: Chris Nelson]