Feeding diverse prey as an excellent strategy of mixotrophic dinoflagellates for global dominance

Microalgae fuel food webs and biogeochemical cycles of key elements in the ocean. What determines microalgal dominance in the ocean is a long-standing question. Red tide distribution data (spanning 1990 to 2019) show that mixotrophic dinoflagellates, capable of photosynthesis and predation together, were responsible for similar to 40% of the species forming red tides globally. Counterintuitively, the species with low or moderate growth rates but diverse prey including diatoms caused red tides globally. The ability of these dinoflagellates to trade off growth for prey diversity is another genetic factor critical to formation of red tides across diverse ocean conditions. This finding has profound implications for explaining the global dominance of particular microalgae, their key eco-evolutionary strategy, and prediction of harmful red tide outbreaks.

Automated summary

Research has shown that mixotrophic dinoflagellates play a significant role in global red tide events due to their ability to combine photosynthesis and predation. Species with low to moderate growth rates, but diverse prey, including diatoms, are responsible for causing red tides worldwide, indicating a strategy of exchanging growth for prey diversity.