In 1977, scientists exploring the deep ocean floor near the Galapagos Islands made a surprising discovery. Around cra in t seafloor wh hot, min-rich wa rises fr below, th found commu of cr, clams, a giant tube worms. No sunlight reaches these depths, so the animals could not depend on plants for energy. Instead, the base of their food chain is bacteria that obtain energy from chemicals in the water.

Type only the missing letters. Each box is one letter, and the number of boxes matches the letters that are missing.