 I'd like to invite Katherine Holland to the stage. She's in the Indian College of Physical and Mathematical Sciences, and the title of Katherine's three minute thesis presentation tonight is One League Under the Sea. Sea water is not for drinking. You'll know this if you've had the misfortune of swallowing a mouthful of it. But what you might not know is in that mouthful there might be hundreds of individual plankton. Plankton are microscopic organisms that drift with the ocean's current. They form the base of the food chain and help to store a lot of the world's atmospheric carbon dioxide through photosynthesis. The plankton eye study also helped to store carbon by using it to build shells that are no larger than a grain of sand. These plankton are called foraminifera. Foraminifera are amazing tiny architects. They build ornate calcium carbonate shells that contain different elements that reflect the chemistry of the sea water that they grew in. For example, when sea water temperatures are warmer, they include more magnesium into their shell, making them a tiny thermometer. Each foraminifera lives for around a month, over this time building a record of what the ocean was like. At the end of its life, all that is left is an empty shell. This shell sinks to the sea floor and settles amongst millions of others like it. Over time, these shells form layer upon layer. Now, as a species, foraminifera have been around for almost 650 million years, all the while diligently recording information about the ocean for scientists to retrieve from the sea floor. It is so important that we understand past ocean and climate interactions so that we might better understand how our ocean now will respond to our rapidly changing climate. Now, it's no use retrieving this information if we can't decipher it properly. Here's where my PhD research comes in. I collect living foraminiferas while scuba diving. I collect them into jars and bring them back to the lab where they continue to grow under controlled conditions. This is so that I can know exactly how their shell chemistry reflects the sea water that they've grown in. So far, we've learned foraminiferas are so good at recording information about the ocean they can tell us how it changes day to day. They're even able to record the subtle effects that other microscopic organisms that live alongside them have on the sea water around them. We're learning there's much more information stored in these shells than previously thought, as though each foraminifera was selflessly live tweeting every living moment. Now, we just have to make use of all of this information. So, the next time you happen to swallow some sea water, take a moment to reflect on the lives of the plankton now inside you.