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This guest blog comes from Dr. Alexander Humphreys, a geology lecturer and researcher at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science. The Khaled bin Sultan Living Oceans Foundation is working with Dr. Humphreys and our partners at UM on a new National Science Foundation (NSF)-funded project, “Protists Prophets,” that is looking at benthic sediment samples collected on the Global Reef Expedition (GRE) to assess the state of the coral reef environment over the past 1,000 years.

I am a modern benthic foraminiferal researcher, which means that I study some of the tiniest organisms in the ocean in order to learn about past environmental conditions on coral reefs. However, before we get to this story, let me first explain a bit about these little critters and their importance to science.

Foraminifera, or forams for short, are protists, which are single-celled amoeba-like organisms that grow a protective shell, called a ‘test’. Today there are roughly 4,000 species of forams and they can be found living in all the world’s oceans, from polar environments to the deepest ocean trenches nearly 11 km down. Forams are important to science because they have short lifespans and are sensitive to environmental change. This sensitivity causes rapid shuffling of species abundances over time as the environmental conditions and climates gradually—and sometime abruptly—fluctuate. When the life of a foram comes to an end, the story does not stop there because even though the organism decays, its hard protective test preserves well and fossilizes, laying down evidence of these population changes in the geologic record—one that goes back 500 million years! I approach this deep fossil record of foraminifera like the pages in a book that tells the story of oceanic and environmental change. The trick is learning how to read the story that these little protists have to tell.