Jane Goodall, with her mascot Mr. H. on March 4, 2004.

Legendary chimpanzee researcher Jane Goodall has died, the conservation organization she founded announced on Oct. 1.

Goodall, 91, died due to natural causes while she was in California on a cross-country speaking tour, according to The Jane Goodall Institute.

"Dr. Goodall’s discoveries as an ethologist revolutionized science, and she was a tireless advocate for the protection and restoration of our natural world," the institute said in statement on social media.

The British ethologist – a scientist who studies animal behavior within their habitat – had no formal training when she embarked on a study of chimpanzees in what would become Gombe Stream National Park in Tanzania, Africa, in the early 1960s. She skyrocketed to fame thanks in part to a National Geographic documentary about her field work and used her science celebrity status to advance conservation efforts for chimpanzees and other endangered species through her eponymous foundation.

"I passionately care about the natural world of which we are a part and which we depend. I love it," Goodall told USA TODAY in 2021. "I passionately care about animals. I want to fight the fact that many are becoming extinct and I want to fight the cruelty."

Who was Jane Goodall?

Born in London, England, in 1934, Goodall had a fascination with animals from a young age. In 1957, she traveled to Kenya where she met Louis Leakey, a Kenyan and British paleontologist and archaeologist whose fossil digs ultimately helped establish that humans evolved in Africa.

Goodall became his secretary and eventually joined him on a field expedition studying chimpanzees on the shores of Lake Tanganyika in what is now Gombe National Park in Tanzania, East Africa.

There she observed chimpanzees using grass stems to pull termites out of their mounds for food, which shattered the mainstream scientific belief that only humans made and used tools and is "considered one of the greatest achievements of twentieth-century scholarship," according to the Jane Goodall Institute.

The National Geographic Society funded more of Goodall's chimpanzee research and sent along cameraman, Hugo van Lawick, to document her efforts. Goodall and van Lawick later married in March 1964, and the documentary, "Miss Goodall and the Wild Chimpanzees," released in 1965, attracted an estimated 25 million viewers in North America upon its first broadcast on CBS.

The couple had one son, Hugo Eric Louis van Lawick, known as "Grub," and divorced in 1974. In 1975, she married Derek Bryceson, who died in 1980.

Goodall, a United Nations Messenger of Peace, was appointed a Dame of the British Empire in 2003 and awarded the U.S. Presidential Medal of Freedom in 2025.

Goodall "worked tirelessly for our planet and all its inhabitants, leaving an extraordinary legacy for humanity and nature," the United Nations said in a post on social media mourning her death.

Jane Goodall spent life, career focused on chimpanzee research

Goodall would go on to publish more than 30 books, star in more documentaries and continue the expansion of research into chimpanzees.

After winning the prestigious Templeton Prize in 2021, which has been awarded since 1972 to luminaries such as Mother Teresa, the Dalai Lama and South African Archbishop Desmond Tutu, Goodall told USA TODAY from the home where she grew up and still lived that she "never planned" to become such an iconic figure.

"There’s basically two Janes - this one talking to you now, sitting here and looking out on my childhood and the other one that’s out there and I don’t know she got there. I have to reconcile the two," she said.

"I try to live up to the one out there and realize I was given gifts and I have to go on using them to the best of my ability," Goodall added.

As a pioneer in her field, Goodall forged a path for many other women to follow in her footsteps including the late Dian Fossey and Biruté Mary Galdikas. The trio, who all studied primates and counted Leakey as a mentor, came to be known as The Trimates or Leakey's Angels.

Galdikas told USA TODAY she was in "absolute shock" over news of Goodall's death. She recalled first meeting Goodall more than 50 years ago in London, and staying in touch over the years, often speaking together and supporting one another's work.

"What she did for chimpanzee conservation is extraordinary. So she truly was an extraordinary person," Galdikas said. "She was an inspiration, I would say, not just to thousands of people, but probably to millions. And her legacy will never die, her legacy will last forever."

In 1977, she founded the Jane Goodall Institute, helping continue the long-running study of chimpanzees in the Gombe and boost conservation efforts for other species around the globe. Its Roots & Shoots program, established in 1991, also engages young people in local efforts to protect animals and the environment.

"Every single day we live, we make some sort of impact on the world. Most of us can choose what sort of impact we make," Goodall told the Detroit Free Press, part of the USA TODAY Network, during a stop on her speaking tour in September. "Hope isn't wishful thinking. I tell people, 'Find something you can do in your community. Do it. Get your friends to support you. See that you can make a difference. Know that all around the world, other people like you are making a difference.'"

This story has been updated to add new information.

Contributing: Karen Weintraub, Reuters

This article originally appeared on USA TODAY: Jane Goodall, iconic wildlife conservationist, has died at age 91

Reporting by N'dea Yancey-Bragg and Keith Matheny, USA TODAY / USA TODAY

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