It’s not just humans that are suffering from the Trump administration’s destruction of the U.S. Agency for International Development. For nearly 40 years, USAID was one of the top global funders of international conservation. In December 2024, shortly before its demise, then-USAID director Samantha Power launched the agency’s sweeping new biodiversity policy, which emphasized locally led development and climate resilience as guiding principles for a $350 million annual conservation portfolio.
A book cover titled "HOMESICK FOR A WORLD UNKNOWN" in bold, light-colored uppercase letters against a black background. Centered in the middle is a horizontal photograph of a person wearing a large backpack, sitting on a rocky ridge and looking out over a vast valley and distant snow-capped mountains under a bright blue sky. Below the title, smaller text reads "The Life of George B. Schaller." The author's name, "MIRIAM HORN," is printed in bold at the bottom.
The seeds of the idea that protecting endangered species is a shared international obligation were planted in the same heady, optimistic era that gave rise to USAID. The early 1960s saw the founding of USAID, the Peace Corps, the nonprofit World Wildlife Fund, and the United Nations Development Program, which became another major backer of conservation. In 1964, the International Union for the Conservation of Nature released its first list of globally threatened species, later known as the “red list,” which remains the benchmark for classifying species as endangered today.
In those same years, as journalist Miriam Horn recounts in her new biography, Homesick for a World Unknown, a headstrong biologist named George Schaller began work that laid the foundation for later global efforts to save species by becoming the first scientist to perform detailed, sustained field studies of once-inaccessible animals in the wild. From Serengeti lions to mountain gorillas, Schaller revealed the lives of creatures long thought monstrous or mysterious. He lived in rustic camp sites for years to document daily behaviors and looming threats, and his work informed later conservation policies as well as today’s spellbinding documentaries.
Schaller, who was born in 1933 in Berlin and moved to the United States in 1947, is widely recognized as the father of modern conservation biology. His work was among the first to tackle, as Horn notes, “the question fundamental to conservation: What does this animal need?” Like a foreign correspondent arriving in a new land and quickly learning the language, customs, and daily rituals, Schaller approached his assignments with near-total immersion, birthing a global movement by peering closer into animal worlds than anyone else had before.
A black-and-white, close-up profile shot of a man looking off to the side. He is wearing a dark, hooded jacket. Behind him is a dense forest of trees and a large, misty mountain peak that rises into a pale sky.
Schaller during his time studying gorillas with Mount Kilimanjaro in the background. Terence Spencer/Popperfoto via Getty Images
So it’s not surprising that his peers thought Schaller was raving mad when, as a 26-year-old biologist, he and his wife, Kay, left New York in 1959 for the Belgian Congo to observe gorillas in the wild for a year. Against all advice, he declined to carry weapons or armor. Other researchers warned him, Horn writes, that “he would be torn limb from limb. All the Great Men of Science said so.”
Schaller was bold, but he was also methodical. “My daily routine of observation varied little,” he wrote in his definitive 1963 account, The Mountain Gorilla: Ecology and Behavior. His days were filled with careful observation, detailed journaling, and patient repetition.
Schaller’s first task was to get the gorillas to ignore him. Each day he would locate them in the rainforest, tracking bent blades of grass or chewed bark, then present himself and sit in full view. If he tried to hide, he might be perceived as a threat or a rival. Instead, he hoped to eventually be accepted as part of the scenery. He moved slowly, and if the gorillas moved away, he did not pursue them; if they approached him, he did not run or show fear.
After several months, he succeeded in what researchers call “habituating” the animals to his presence—a practice later adopted and refined by his successors studying great apes, including Jane Goodall and Dian Fossey. The approach enabled the first sustained, detailed, and up-close observations of wild animals. “I could only obtain unbiased data on their behavior if they remained relatively unaffected by my presence,” he wrote.
Gorillas, Schaller discovered, are not brutish or particularly aggressive. Save for the occasional clashes between males challenging each other for dominance, they prefer loafing over fighting and spend most of their time napping and snacking on wild celery and other plants. Other than the odd insect, their diets are strictly vegetarian.
Schaller recorded what they ate, where they slept, how they socialized, how they cared for infants—painting the first detailed picture of their daily lives and what they needed to survive. This information, later expanded by other biologists, would become essential to future conservation efforts. By the early 1980s, the combination of rapid habitat loss and poaching had left mountain gorillas, which only live on forested summits in Rwanda, Uganda, and the Democratic Republic of the Congo, critically endangered. The population of gorillas that Schaller had estimated to be around 450 had shrunk to around 250. (Another smaller population, not yet discovered at the time, meant the overall number was a bit larger.) Many scientists, including Fossey, believed they were on the path to extinction.
