Researchers from UH Manoa released a study of the Indo-Australian sponge, an invasive species that has been documented in Hawaii’s coral reefs since the late 1990’s. The study found that the sponges do not photosynthesize microbes as corals do, but rather harvest essential amino acids from bacteria within their own bodies.
This shows a symbiotic relationship between the sponges and their bacteria that is unique among complex animals. Sponges obtain nutrients from the water around them to feed their bacteria, which the bacteria then use to produce amino acids that feed the sponge.
“The symbiosis we see between the sponge and its microbial community is remarkable,” said lead researcher Dr. Joy Leilei Shih. “The intimate relationship between sponges and their symbionts developed over their long evolutionary history. Sponges are the oldest multi-cellular animal on earth. That’s why they are so well-adapted and resilient.”
The implications are important to Hawaii’s marine ecosystems. Sponges have a substantial effect on the nutrient dynamics in coral reef systems. As corals continue to decline due to human activity and climate change, sponges may soon come to dominate the reefs.