Jane Goodall's cause of death during US tour revealed

Legendary primatologist Dame Jane Goodall died earlier this month of causes which can now be revealed. According to her death certificate, the 91-year-old suffered a cardiopulmonary arrest in California, US, on October 1. A host of celebrities and royalty previously paid tribute to Dame Jane, who devoted her life to primates, with her research on chimpanzees the longest field study ever undertaken of any group of animals in the wild.

Prince William penned a personal tribute to the conservationist saying she had "boundless curiosity, compassion and pioneering spirit transformed our understanding of the natural world". His words followed those of his brother the Duke of Sussex, who forged a close bond with the famed primatologist and described her as "a visionary humanitarian, scientist, friend to the planet, and friend to us".

American entertainment news site TMZ reported the revered conservationist's cause of death, citing the Department of Public Health in Los Angeles.

Born in London in 1934, Dame Jane began researching free-living chimpanzees in Tanzania in 1960. She arrived at Gombe Stream National Park on the shores of Lake Tanganyika in July of that year, a time when it was unheard of for a woman to venture into the wilds of Africa.

It was there she observed a chimpanzee named David Greybeard make a tool from twigs and use it to fish termites from a nest, a ground-breaking observation that challenged the definition of humans as the single species capable of making tools.

TV presenter Sir David Attenborough has praised conservationist Dame Jane as a "tireless advocate" for chimpanzees and a "great champion of environmental protection"

Sir David, 99, who was friends with Dame Jane and is best known for his BBC nature documentaries, said in a statement: "Jane Goodall was the first to prove that an investigating scientist and a great ape living in the wild could become true friends and in doing so she came to transform our understanding of chimpanzees.

"She was their tireless advocate and a great champion of environmental protection."

Oscar-winning actor and environmental campaigner Leonardo DiCaprio also expressed his tribute to his "dear friend" and personal "hero". He said "we all must carry the torch" for Dame Jane" and protect "our one shared home", in a post to Instagram on Wednesday.

The Titanic star, 50, shared photos of him and Dame Jane who was made a UN Messenger of Peace in 2002, 12 years before DiCaprio was also given the honorific title. "Today we have lost a true hero for the planet, an inspiration to millions, and a dear friend," DiCaprio said.