"Everyone watches the fish swimming above. But the real action — the cities of life no one talks about — is down in the mud. Millions of creatures live on and in the seafloor, hidden from sight."
The Hidden World on the Bottom
Most people picture ocean life as fish swimming in open water. But an enormous share of ocean biodiversity lives on and in the seafloor — the benthic zone. These bottom-dwellers are split into two groups: infauna, which burrow into the sediment (worms, clams, burrowing shrimp), and epifauna, which live on top of it (crabs, sea stars, urchins, flatfish). Seafloor life is easy to overlook because it's hidden under water and often under mud, but it's the foundation of the ocean food web and includes some of the strangest animals on Earth. This lesson explores who lives down there, how they survive in dark, low-food conditions, and why protecting the seafloor protects the whole ocean.
