Tiny ocean grazers create most of Earth's oxygen
Invisible zooplankton graze on phytoplankton, forming the base of aquatic food webs and producing most of Earth's oxygen, a vital process for all life.
Microscopic zooplankton, the tiny drifting animals of our oceans and freshwater, are unsung heroes. They graze on phytoplankton, microscopic algae that form the base of aquatic food webs. This crucial interaction transfers energy, sustaining everything from small fish to massive whales. Phytoplankton, through photosynthesis, produce an estimated 50 to 85 percent of the Earth's oxygen as a byproduct. Without this foundational relationship, aquatic food chains would collapse, impacting global biodiversity and fisheries that feed billions. This grazing also helps regulate the carbon cycle, contributing to our planet's natural climate balance.