There are few people in human history whose last names alone are sufficient to conjure up kindness, goodness, wisdom, grace—Mandela, Gandhi, King, Lincoln. Add to that list Goodall. The other four left us years ago. Jane Goodall—primatologist, zoologist, anthropologist, conservationist, winner of the U.S. Presidential Medal of Freedom, and Dame Commander of the Order of the British Empire (DBE)—joined them today, dying at age 91.“Dr. Jane Goodall DBE, U.N. Messenger for Peace and founder of the Jane Goodall Institute, has passed away, due to natural causes. She was in California as part of her speaking tour in the United States” the Jane Goodall Institute posted on Instagram. “Dr. Goodall’s discoveries as an ethologist revolutionized science, and she was a tireless advocate for the protection and restoration of our natural world.”[time-brightcove not-tgx=”true”]The spare prose of the announcement was a fitting reflection of the quiet, austere, deliberate way Goodall lived her remarkable life—qualities that were essential for work that required hours, months, and years crouched in the jungles and clearings of Africa, most notably in the Gombe National Park in Tanzania, observing chimpanzees from a sort of intimate distance and discovering their sometimes loving, sometimes violent, sometimes ingenious lives.It was in 1960 that Goodall first arrived in Gombe, part of a group of three young naturalists—including Dian Fossey and Biruté Mary Galdikas—whom famed anthropologist Louis Leakey dispatched to Africa to study primates in their natural environment. Leakey playfully dubbed them The Trimates. All three women distinguished themselves. Galdikas spent 50 years studying the orangutans of Indonesian Borneo in their native habitat. Fossey dedicated herself to studying mountain gorillas in their Congo homeland, and lost her life in their cause: in 1985 she was murdered in her cabin in Rwanda while working to protect the gorillas from poachers. Goodall had the gift of years—and the gift of patience—and over the decades her discoveries spilled forth.In 1960, she witnessed a group of chimpanzees eating a bushpig, doing away with the previous belief that chimps were strictly vegetarians. That same year she made the startling observation that chimps strip the bark from twigs and use the denuded stick to fish for termites in rotting logs—overturning the even more closely held belief that humans are the only animal to use tools. Chimps, she discovered, mirror humans in other, decidedly less benign ways. From 1974 to 1978 she observed what she dubbed “the four year war,” an extended, bloody conflict between two groups of rival chimpanzees in Gombe—groups she called the main Kasakela group and the Kahama splinter group. That same year she observed cannibalism among chimpanzees, when a mother and daughter pair stole, killed, and ate babies in their own community—likely to eliminate a line of rival females.But Goodall discovered a gentle side to chimpanzees too. They play, they tickle, they kiss, they grieve. They make submissive, gestural apologies after a quarrel. And, in powerful moments of cross-species care, they sometimes accepted her—the quiet, comparatively hairless, human observer—as part of their band. In 2009, Goodall spoke to TIME’s Andrea Sachs about her time in the field, and shared some of her most treasured exchanges with the chimps. In one such moment she was following a young male through the jungle, fighting her way through the brush and the scrub and catching thorns in her hair as the chimp hurried ahead. Finally she reached a clearing—an open space across which the chimp could have easily hurried if he was trying to leave his pursuer behind. Instead, she found him sitting quietly, apparently waiting for her. Touched by the gesture, she found a palm nut on the ground—something chimps love—picked it up and held it out to him. At that moment, however, the chimp wasn’t hungry.“He turned his face away,” she recalled. “So I put my hand closer. And he turned, he looked directly in my eyes, he reached out, he took the nut … he dropped it, but he very gently squeezed my hand, which is how chimpanzees reassure each other. That was a communication that, for us, pre-dates words.”On another occasion, she was observing a young mother she named Flo and her five-month-old baby, who was just learning to walk. “[Flo] trusts me so much that when he totters towards me, and reaches out, she doesn’t snatch him away like she used to, but she just keeps her hand protectively around him and she lets him reach out to touch my nose. And this was just so magic.”Flo wasn’t alone in trusting Goodall. The billions of members of Goodall’s own species did too. We trusted her to be something of an ambassador between the human nation and that of our closest genetic kin. We trusted her to be an advocate for nature and for conserving the wild world. And it was a trust that was rewarded.In her final article for TIME, in 2021, Goodall took up the cause not of fauna, but flora, writing about the devastating consequences the planet could suffer as millions of acres of trees are cut, razed, and burned every year. At one time, she wrote, the planet was home to six trillion trees. Now that number has been halved—mostly in the last 100 years. She called on readers to support the Trillion Trees campaign—a drive to plant one trillion trees by 2030. And she lent her name to a similar effort—the Trees for Jane initiative. From space, Goodall wrote, our planet is a palette of white and blue and brown and green—and the green is in retreat.“One trillion trees planted and protected is a big number, even over a ten-year period,” she wrote. “But if everyone pitches in, we have a fighting chance to make a difference. Together, let’s create a sustainable planet for generations to come. Join us today. Let’s give our planet a new reason for hope.”In her near-century of life, Goodall was all about the hope. In her final conversation with TIME, also in 2021, she said, “I’m about to leave the world with all the mess, whereas young people have to grow up into it. If they succumb to the doom and gloom that’s the end. If you don’t hope you sink into apathy; hope is a crucial way to get through this.“Goodall’s long, heartening campaign ended today. Let’s now see if we’re all worthy of her work.