British primatologist Jane Goodall, who transformed the study of chimpanzees and became one of the world’s most revered wildlife advocates, has died at the age of 91, her institute announced.

Goodall “died peacefully in her sleep while in Los Angeles” on a speaking tour of the United States, the Jane Goodall Institute said in a statement on Instagram.

In a final video posted before her death, Goodall, clad in her trademark green, told an audience: “Some of us could say ‘Bonjour,’ some of us could say ‘Guten Morgen,’ and so on, but I can say, ‘Hoo-hoo-hoo-hoo-hoo-hoo-hoo! That’s ‘good morning’ in chimpanzee.’”

Tributes poured in from conservationists, politicians, and entertainers.

“I’m deeply saddened to learn about the passing of Jane Goodall, our dear Messenger of Peace,” said UN chief Antonio Guterres. “She is leaving an extraordinary legacy for humanity & our planet.”

“Renowned zoologist, primatologist, researcher and a friend of Tanzania, Dr. Goodall’s pioneering work at Gombe National Park transformed wildlife conservation, and placed our country at the heart of global efforts to protect chimpanzees and nature,” said Tanzanian President Samia Suluhu Hassan.

“I think the best way we can honor her life is to treat the earth and all its beings like our family, with love and respect,” said actress Jane Fonda, herself an environmental activist. “I loved her very much.”

Transformative discoveries

Born in London on April 3, 1934, Goodall grew fascinated with animals in her early childhood, when her father gave her a stuffed toy chimpanzee that she kept for life. She devoured Tarzan books, about a boy raised by apes who falls in love with a woman named Jane.

In 1957 she traveled to Kenya at a friend’s invitation and began working for the renowned palaeoanthropologist Louis Leakey, who dispatched her to study chimpanzees in Tanzania. She became the first of three women he chose to study great apes in the wild, alongside American Dian Fossey and Canadian Birute Galdikas.

Goodall’s most famous finding was that chimpanzees use grass stalks and twigs as tools to fish termites from their mounds.

Leakey urged her to pursue a doctorate at Cambridge University, where she became only the eighth person ever to earn a PhD without an undergraduate degree.

Goodall also revealed chimpanzees’ capacity for violence—from infanticide to long-running territorial wars—challenging the belief that our closest cousins were inherently gentler than humans.

In 1977 she founded the Jane Goodall Institute to further research and conservation of chimpanzees. In 1991 she launched Roots & Shoots, a youth-led environmental program that today operates in more than 60 countries.

Her activism was sparked in the 1980s after attending a US conference on chimpanzees, where she learned of the threats they faced: exploitation in medical research, hunting for bushmeat, and widespread habitat destruction.

From then on, she became a relentless advocate for wildlife, traveling the globe into her nineties.

Goodall married twice: first to Dutch nobleman and wildlife photographer Baron Hugo van Lawick, with whom she had her only child, Hugo Eric Louis van Lawick, who survives her.

That marriage ended in divorce and was followed by a second, to Tanzanian lawmaker Derek Bryceson, who later died of cancer.

Message of empowerment

Goodall wrote dozens of books, appeared in documentaries, and earned numerous honors, among them being made a Dame Commander by Britain and receiving the US Presidential Medal of Freedom from then-president Joe Biden.

She was also immortalized as both a Lego figure and a Barbie doll, and was famously referenced in a Gary Larson cartoon depicting two chimps grooming.

“Conducting a little more ‘research’ with that Jane Goodall tramp?” one chimp asks the other, after finding blonde hair. Her institute had its lawyers draft a threatening letter, but Goodall herself waved them off, saying she found it amusing.

“The time for words and false promises is past if we want to save the planet,” she told AFP in an interview last year.

Her message was also one of empowerment.

“Each individual has a role to play, and every one of us makes some impact on the planet every single day, and we can choose what sort of impact we make.”