RACHEL MARTIN, HOST:

Good morning. I'm Rachel Martin. Researchers have identified the world's largest plant underwater, covering almost 80 square miles off the coast of Western Australia. According to scientists, what looks like a massive meadow of sea grass is actually a single seedling that's been cloning itself over and over. One researcher calls it bizarre to see a plant in one end of the bay and find the same plant a hundred kilometers away. It's been thriving that way for 4,000 years. It's MORNING EDITION. Transcript provided by NPR, Copyright NPR.