Learn about one of nature's unsung superheroes, their amazing contributions to our ecosystems, and how saving freshwater mussels means saving a lot more than you might think. Freshwater mussels don't get as much attention as cute furry animals, but they're more than just shells sitting at the bottom of a stream. This title from our Nature's (Secret) Superheroes series delves into the powerful effect mollusks have on their environment. From fighting pollution to signaling the alarm when things have gone wrong with a waterway, learn how these underappreciated and often overlooked environmental superheroes work to keep their ecosystems going strong. Did you know: Not only don't mussels have eyes or ears, but they also don't even have heads or brains! Mussels can be as small as a fingernail or as big as a dinner plate Some mussels can live to be 100 years old! A single mussel can filter 20 gallons of water a day! The Nature's (Secret) Superheroes series--covering bats, native bees, beavers, elephants, freshwater mussels, and vultures--follows a fun superhero theme, featuring each animal's origin story, how it saves the day, and its nemeses. Each book also includes activities that allow readers to gain hands-on knowledge about these animals.