The tropics are the most biodiverse part of the world. Some tropical rainforests are home to more species than entire continents, and tropical coral reefs are believed to have the highest biodiversity of any marine ecosystem on the planet. But thanks to human action—specifically, the actions of the fossil fuel industry, Big Ag, and other planet-destroying corporations—those ecosystems are facing collapse.
One November night each year, beneath the full moon, more than 130 species of corals simultaneously spawn in Australia’s Great Barrier Reef. Some corals spew plumes of sperm, smoldering like underwater volcanoes. Others produce eggs. But most release both eggs and sperm, packed together in round, buoyant bundles as small as peppercorns and blushed in shades of pink, orange, and yellow.
For the past three weeks, biologists aboard the NOAA ship Okeanos Explorerhave been investigating marine sanctuaries in the American Samoan region of the Pacific. They’ve found a smattering of weird and dazzling creatures, reminding us just how little we know about life at the bottom of the ocean.
DEEP DOWN IN the ocean, 200 to 500 feet below the surface, lifeforms flourish where they shouldn’t. Down here, little light penetrates, which is somewhat of a problem for solar-powered creatures like coral. Yet here, stubbornly, the reefs still sprawl, supporting hordes of fish and invertebrates, forming an ecosystem that’s almost totally foreign to science. This is the mysterious “twilight zone.”
For the past year, the world’s corals have been getting increasingly pummeled by climate change. Now with El Niño kicking ocean heat into overdrive, much of the world’s oceans have turned deadly for the world’s corals.