by Fiona Bayrock
Actually, the farts (aka fast repetitive ticks) come from air that the herring gulp at the surface, not from food. They release bubble streams in order to "talk" to each other. This is just one of the fascinating ways that animals use bubbles. Besides communication, bubbles are used for travel (violet sea snails), warmth (otters), protection (spittlebugs), and more. Even humans use bubbles: as curtains to protect fish from the lethal sound waves produced during underwater construction. The book also includes a section with additional facts, a glossary, and a short index.