John Muir, a Scottish-American naturalist and conservationist, is widely regarded as the father of American conservation due to his passionate advocacy for the preservation of wilderness and his instrumental role in establishing national parks, including Yosemite and Sequoia.

Gifford Pinchot, the first chief of the United States Forest Service, advocated for the "wise use" of natural resources, emphasizing the sustainable management of forests and other natural resources for the benefit of both present and future generations.

Aldo Leopold, an American ecologist and forester, wrote "A Sand County Almanac", a collection of essays that explored the ethical and ecological dimensions of conservation and introduced the concept of a "land ethic" that emphasized the interconnectedness of humans and the natural world.

Rachel Carson, an American marine biologist and conservationist, published the influential book "Silent Spring" in 1962, which exposed the devastating effects of pesticides, especially DDT, on wildlife and the environment, sparking a global movement to ban the use of harmful chemicals.

John Muir founded the Sierra Club in 1892, an influential environmental organization dedicated to protecting and preserving the natural resources of the Sierra Nevada mountains and beyond.

Stephen Mather, the first director of the National Park Service, played a pivotal role in establishing and managing the National Park System, overseeing the expansion and protection of national parks and monuments.

Aldo Leopold co-founded the Wilderness Society in 1935, an organization dedicated to protecting wilderness areas and promoting the preservation of natural ecosystems.

Sylvia Earle, a renowned marine biologist and oceanographer, has dedicated her life to the conservation of marine environments, advocating for the protection of endangered species and the preservation of the health and biodiversity of oceans.

Rachel Carson was a founding member of The Nature Conservancy, a conservation organization dedicated to protecting ecologically significant lands and waters for the benefit of nature and humanity.

Norman Myers, a British environmentalist and conservation biologist, has been a leading advocate for the conservation of tropical rainforests and the promotion of sustainable development, highlighting the importance of biodiversity and the threats posed by deforestation.

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) was signed in 1973 to regulate the international trade of endangered species and their products, aiming to protect them from overexploitation and extinction.

Jane Goodall, a renowned primatologist and conservationist, has dedicated her life to the study and protection of chimpanzees in Tanzania, advocating for the conservation of African wildlife and the establishment of national parks to safeguard their habitats.

Dian Fossey founded the Dian Fossey Gorilla Fund International in 1967 to protect mountain gorillas in Rwanda, conducting groundbreaking research on their behavior and advocating for their conservation.

Birutė Galdikas, a Canadian primatologist and conservationist, has dedicated her life to the study and protection of orangutans in Borneo, advocating for the conservation of their rainforest habitat and the establishment of protected areas.

Cynthia Moss founded the Amboseli Elephant Research Project in 1975 to study and protect elephants in Amboseli National Park, Kenya, conducting long-term research on their behavior and ecology.