Photograph by Hugo Van Lawick
Jane Goodall's story of a young girl who loved animals and dreamed of going to Africa—and who found a way of making that dream come true-is also one of the great scientific sagas. Goodall's longstanding study of chimpanzee behavior at Gombe Stream, Tanzania, demonstrating how closely chimpanzees resemble humans-and humans chimpanzees-has caused a revolution in how we understand ourselves.
Photograph by Kris Krug
Medical researcher Hayat Sindi employs her high-tech expertise to devise low-tech diagnostic tools to help improve health care in the world's poorest communities. A native of Saudi Arabia who earned a Cambridge University Ph.D. in biotechnology, she says that "my mission is to find simple, inexpensive ways to monitor health that are specifically designed for remote places and harsh conditions."
Photograph by Philip Scott Andrews
Although she grew up in a grass-and-mud hut, Kakenya Ntaiya is using bricks and mortar to build the first school for girls in her rural Kenyan village. This teacher, who refused to accept a Maasai woman's traditionally subservient role, is hoping that by expanding educational and leadership opportunities for girls she can improve life for entire villages as well.
Photograph by Michael and Patricia Fogden, Minden Pictures
A casting master employs her "master caster" to fling ropes high into what she calls the "last biotic frontier," the incredibly diverse tree canopies of tropical forests. Nalini Nadkarni spends her working hours dangling from a body harness hundreds of feet above the ground in Costa Rica's Monteverde Cloud Forest, where global warming is threatening many rare and little known species.
Photograph by John Stetson, Will Steger Foundation
When she was just 18, Sarah McNair-Landry became the youngest person ever to ski to the South Pole. That feat alone would justify her selection as a National Geographic Young Explorer, but remarkably enough, the Canadian has also sledged to the North Pole and crossed some 1,400 miles of forbidding Greenland ice cap—all to draw attention to the dangers of global warming.
Photograph by Kip Evans
Twelve astronauts had stepped onto the moon before the first human—Sylvia Earle, wearing a pressurized hard shell diving suit—walked on the equally alien seafloor some 1,200 feet beneath the surface. "Her Deepness" has since become the most eloquent of ocean advocates, and as director of the National Geographic-supported Sustainable Seas Expedition, spent five years exploring the 12 largely uncharted U.S. marine sanctuaries.
Photograph by Bobby Model
As the first woman to traverse Papua New Guinea and the first person to kayak 600 miles down Africa's Niger River to Timbuktu, Kira Salak has been called "the gutsiest—and some say craziest—woman adventurer of our day." But for this writer and literary scholar, such hazardous expeditions are as much about interior journeys as they are outward adventures.
Photograph by David Doubilet
Though she sometimes described herself as a diver first and a scientist second, Eugenie Clark (at left) was one of only a handful of women ichthyologists in the world in the 1940s, when she began her long career. A pioneering investigator of shark behavior, it was as the "Shark Lady" that she became one of National Geographic's most popular contributors.
Louise and Meave Leakey
Photograph by Mike Hettwer
It was bred in the bone that Louise Leakey (right) become a bone hunter. Her mother and partner is Meave Leakey (left), one of today's leading paleoanthropologists, and her father is Richard Leakey, whose own excavations in Kenya remain milestones in the field. Furthermore, her grandparents were Louis and Mary Leakey, whose discoveries in Tanzania's Olduvai Gorge originally proved that Africa, and not Asia, was the birthplace of humankind.
Photograph by Vassiliy Pivtsov
Growing up among the Alps of her native Austria, Gerlinde Kaltenbrunner set herself a goal: She would climb every Himalayan mountain over 8,000 meters high. One after another this trained nurse scaled such legendary peaks as Everest, K2 (seen here), and Annapurna, until she became the first woman to summit all 14 of them without relying on supplemental oxygen.
Photograph by Robert I. M. Campbell
Dian Fossey spent 18 tempestuous years (1967-85) studying endangered mountain gorillas in Rwanda's Virunga Volcanoes. She was also devoted to their care and protection. Though it came at the cost of her life—she was eventually murdered, probably by poachers, on whom she had waged a relentless war—Fossey awakened the world to the plight of these gentle creatures.
Photograph by Andre Camara
Emily Ainsworth had just graduated from Oxford when she ran away to join the circus. Her adventures-as "Princess Aurora"—with a wandering troupe in Mexico, which also featured a cranky harmonica-playing elephant, launched her on a career photographing some of society's more intriguing subcultures: butchers, fishmongers, transvestites, you name it.