The Endangered Species Act is more than 40 years old, which begs the question: Where are they now? “They” being the thousands of threatened plant and animal species that are protected under the landmark legislation. Maintaining biodiversity is no easy feat, but many species have rebounded since the act’s inception in 1973. So far, 59 species have been delisted, 20 of which are considered true success stories. But others haven’t been so lucky. An animal can be taken off the list if it is no longer threatened or if it goes extinct. Today, more than 1,400 plants and animals remain endangered or threatened.