LOS ANGELES, California: Tributes poured in from world leaders, celebrities, and conservationists following the death of Jane Goodall, the pioneering primatologist whose intimate studies of chimpanzees transformed science and inspired a global movement for the planet. She was 91.

The Jane Goodall Institute said the renowned British scientist died of natural causes in Los Angeles on October 1 while on a U.S. speaking tour. She had been scheduled to meet students and teachers in Pasadena to help launch the planting of 5,000 trees in wildfire burn zones; organizers learned of her death as the event was about to begin. After a moment of silence, the first tree was planted in her name.

Goodall rose to international fame in the 1960s after documenting wild chimpanzees in Tanzania using tools and showing complex emotions—behaviors previously thought unique to humans. Her work not only redefined the boundaries of science but also reshaped humanity's understanding of its closest relatives.

Over six decades, she became one of the world's most recognizable conservationists. Her soft-spoken advocacy resonated across generations through documentaries, television appearances, and tireless global tours.

Former U.S. President Joe Biden, who awarded Goodall the Presidential Medal of Freedom, said she mobilized "a global movement to protect the planet." Barack Obama praised her ability to connect people to "the natural wonders of our world," while Bill Clinton urged redoubled efforts to defend the environment in her memory.

UN Secretary-General António Guterres called Goodall "our dear Messenger of Peace," saying she leaves "an extraordinary legacy for humanity and our planet." Canadian Prime Minister Mark Carney hailed her as a "tireless guardian of nature."

Tributes also came from philanthropist Melinda French Gates, who said Goodall "fundamentally changed the way we understand the world." Actor Leonardo DiCaprio, who called her "my hero," adding, "She inspired millions to care, to act, and to hope. She never stopped."

Journalist Maria Shriver described Goodall as a "legendary figure and a friend," while PETA founder Ingrid Newkirk said she "forever changed the way we view our fellow animals." Environmental broadcaster Chris Packham noted that "Jane just died on the job—the job her life became: protecting life on Earth."

Goodall's influence reached beyond science, inspiring countless young people through her Roots & Shoots youth program and her unrelenting advocacy for conservation. Her quiet determination, colleagues said, made her one of the most effective voices in the global fight to protect nature.

"She revolutionized science, and she was a tireless advocate for the protection and restoration of our natural world," the Jane Goodall Institute said.