Pesticides bioaccumulate up the food chain, silently killing unintended animals.
Carson described springs where birds no longer sang, because pesticides sprayed on fields built up in insects, then in the birds that ate them. The higher you go up the food chain, the more concentrated the poison becomes. Her book showed nature is far more connected than it first appears.
Why it matters The book led directly to the ban on DDT and to the birth of the modern environmental movement.