The Ocean is Glowing with Microorganisms

Photo credit: common domain

Mosquito Bay in the Caribbean island of Vieques literally lights up at night. This is because it is home to almost a million individuals of Pyrodinium bahamense, a specie of tiny dinoflagellates that you can’t see during the day but lights up at night through bioluminescence. Much of the life in the ocean is tiny, from the tiny glowing creatures of the shallow and deep, to phytoplankton that build the base of the marine food web, and chemotrophic bacteria and archaea in hydrothermal vents. Though these organisms might be hard to see, they light up the sea with a deluge of life.

Guiding Questions

  • What kinds of microscopic organisms live in the ocean?
  • What do these microscopic organisms do for our planet and oceans?
  • How does size of different phytoplankton relate to temperature of water they live in?
  • Why do deep sea vents host so much life?


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External Resources

Cross-cutting Concepts

  • C4: Systems and System Models
  • C6: Structures and Functions

Disciplinary Core Ideas

  • ESS2.C: The Roles of Water in Earth's Processes
  • LS2.B: Cycles of Matter and Energy Transfer in Ecosystems