can change their physiology quite rapidly, the fluorescence data is able to give us an immediate insight into what’ s going on in our experimental bottles.
I’ m often asked what’ s so important about phytoplankton, and why I bother studying them at all. I think the most easily appreciated example of their significance is in the incredible diversity of the Southern Ocean. Every day of our cruise has been filled with wildlife of some description, whether it’ s a majestic albatross gliding effortlessly along the air currents, porpoising penguins bouncing through the water, or a pair of chubby seals hauled out on an ice floe. The mainstay of many of these animals is krill, either eating it directly, or feeding on the fish and assorted invertebrates that prey on it. The krill in turn are sustained by phytoplankton, the marine world’ s main primary producers that use the sun’ s light to convert carbon from the inorganic form of carbon dioxide into organic compounds that can be used by living things.
The diverse result of phytoplankton productivity. Left to right: black-browed albatross, chinstrap penguins, fin whale( top row); crabeater seals, snow petrel, Antarctic fur seal( second row); wandering albatross, cape petrels, Antarctic minke whale( bottom row) @ Laura Bretherton
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