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Images: A Day in the Life of a Phytoplankter

With backgrounds in engineering, biology, and philosophy, WHOI scientist Sam Laney has a unique perspective on his research. Laney studies phytoplankton, the abundant microscopic plant life at the base of the ocean's food webs. He wants to know what life is like for phytoplankton cells as individuals, and how they adapt to rapidly changing conditions. (Photo by Carin Ashjian, Woods Hole Oceanographic Institution)

Single-celled phytoplankton carry out photosynthesis within specialized organelles called chloroplasts. Like factories, the chloroplasts' photosynthetic machinery requires raw materials and energy—sunlight—to operate. Cells living in the ocean must rapidly adapt to varying light levels caused by intermittent cloudy and bright conditions.
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(Illustration by Amy Caracappa-Qubeck and Katherine Joyce, Woods Hole Oceanographic Institution)

Scientist Sam Laney and research assistant Emily Peacock studied the types and abundance of phytoplankton in Arctic water on a 2010 cruise aboard the U.S. icebreaker Healy. An "ice liberty" afforded a chance to get a short distance away from the ship for a brief time. (Photo by Karen Romano Young)

On a recent research cruise to the Artic, WHOI research assistant Emily Peacock, a member of Sam Laney's lab, operated  an Imaging FlowCytobot, an instrument that images and identifies individual phytoplankton cells in ocean water. Sam Laney adapted the instrument, first developed by WHOI biologists Heidi Sosik and Rob Olson, for use at sea and to investigate phytoplankton populations in polar waters. (Photo by Karen Romano Young)

Diatoms, a type of phytoplankton, can be single cells or form chains of cells. The seagoing Imaging FlowCytobot took this image of a chain-forming diatom from Arctic waters on a 2010 research cruise. In this diatom species, long spines protruding from the cells hold the cells together as a group. (Image courtesy of Sam Laney, Woods Hole Oceanographic Institution)

This image, taken on the same Arctic cruise with Sam Laney's seagoing Imaging FlowCytobot instrument, shows chain-forming diatoms in the act of dividing asexually. The pair of cells on the left has recently divided, producing two daughter cells from one parent cell. The cells on the right are still in the process of dividing. The daughter cells are building new cell walls between them, but are not yet fully separated from each other. Daughters differ slightly in size, though it is not obvious in this image. (Image courtesy of Sam Laney, Woods Hole Oceanographic Institution)

Phytoplankton are the base of ocean food webs, like grass on the prairie. When nutrients and sunlight are plentiful, microscopic phytoplankton cells develop huge population explosions called blooms. Some blooms are so massive that they tint the water and can be seen from space, as in this satellite image of a bloom between New Zealand's North and South Islands. Different colors swirling in the ocean−white, green, and brown−are likely due to different kinds of phytoplankton, including diatoms. (NASA Ocean Color Group)