The Postal Service is celebrating 50 years of the Endangered Species Act with the release of new stamps on May 19.
The Endangered Species pane features 20 animals that represent more than 1,300 species that are currently protected by the law.
President Richard Nixon signed the landmark legislation in 1973. Since then, other nations worldwide have adopted similar protections.
The act states that living things have “esthetic, ecological, educational, historical, recreational and scientific value to the Nation and its people,” and that species are also entitled to exist for their own sake.
Habitat loss is the chief cause of species vulnerability, with human activity accounting for roughly 99 percent of all modern-day extinctions. Pollution, climate change, the introduction of invasive species and overhunting all contribute to species decline.
Under the law, imperiled wildlife and plants receive special protections to improve their prospects for survival. Since it began, scientists estimate that hundreds of species in the United States have been rescued from the brink of extinction, including the national symbol, the bald eagle.
The Forever stamps will be available in panes of 20 at Post Offices and on usps.com.