Science & People

Louis Leakey and Mary Leakey | Origins of the humankind

Sometimes great scientists make their greatest discoveries while they are working with a partner. This was true for Marie and Pierre Curie, who complemented each other's work in their research on radioactivity, and Louis Leakey and Mary Leakey, who pioneered research on the origins of man in East Africa. A large number of expeditions worked together on the excavation, making the name Leakey equivalent to research on human evolution and undoubtedly proved that humans first appeared in Africa. Louis and Mary Leakey traced the origins of the human lineage for a period spanning 18 million years to learn more about the ape-like ancestors of Homo sapiens. They discovered the first human being to make a tool and named it Homo habilis.

Louis Leakey and Mary Leakey

They also made independent inventions. Mary found fossil footprints that show the first humans walking upright three million years ago – about a million years before our ancestors started making tools. The visionary Louis helped launch the first long-term field studies of wild primates by sending Jane Goodall to record chimpanzee behavior, and Dian Fossey to observe mountain gorillas, and Birute Galdikas to observe orangutans. These studies helped shape our understanding of the social lives and cultures of our early ancestors. Together, Louis and Mary transformed paleoanthropology from just stone and bone hunting into the rich and advanced science of today.

Although Mary Leakey made many of their most important discoveries, Louis Leakey was the person who fueled the work. The idea of ​​seeking our first ancestors in Africa by leaving aside the prevailing scientific common sense, was his own. At the time, paleoanthropologists believed that humans migrated to Africa after evolving in Europe and Asia. Louis proved this idea wrong and over time, with Mary's contributions, completely ruled out the old belief.

Louis's bias in favor of Africa was partly due to his origins. His parents were missionaries who lived with the people of Kikuyu in a village in the mountains above Nairobi, in British colonial East Africa (now Kenya). Although his parents were English, Louis always saw himself more as a Kikuyu. He was the first white boy born among the Kikuyus, they accepted him into their lives. When he was 11, he joined the secret reception ceremony of the tribe with other children his age and became a member of the Mukanda.

His parents had hired a teacher for his two older sisters, his brother, and himself but he eventually did not receive a regular education. Louis had plenty of time to participate in even more interesting events and adventures with the Kikuyu blood brothers. He learned their language, to hunt with a bow and arrow, make traps, trace, and even hunt animals with bare hands. He would link his seemingly sudden insights into early humans to his Kikuyu education.

Exploring ancient Africa

The Olduvai Gorge in Tanzania also stands out for its very colorful terrain.
The Olduvai Gorge in Tanzania also stands out for its very colorful terrain.

However, it was the book from his cousin at Christmas that took him on this professional path. The book Days Before History was about the adventures of an English boy named Tig who lived in the Stone Age. Stone Age people and the tools they made had drawings and dates on them. As inspiration from the book, Louis began collecting glass rocks that he found in eroded carvings with streams around his houses. His family made fun of his "broken bottles," but Louis had an independent streak.

He then consulted the only scientist he knew, Arthur Loveridge, the curator of the small natural history museum in Nairobi. Loveridge studied them and said that some of them were definitely "tools" and explained to him that he knew little about the Stone Age in Africa. These words changed Louis's world; now he had research to pursue in his entire life. In his autobiography named White African, he writes, "I definitely decided to go down this road until everything about the Stone Age [in Africa] was known". He had just turned 13 years old.

It was not easy for Louis to acquire his desired profession. His schooling was limited to the few years he attended school in England during his off days, but he managed to close this gap by working hard and was accepted into St John's College, Cambridge. After earning a dual bachelor's degree in anthropology and modern languages ​​(one was Kikuyu), he received a small research fellowship.

On this scholarship, he bought a ticket to a ship to Kenya and organized the first East African archaeological expedition in the summer of 1962. One of the Cambridge professors tried to dissuade him by saying that he wasted his time looking for the first people in Africa because "everybody knows they started in Asia". Such negative remarks made Louis even more determined to find the evidence he is looking for and prove the professor wrong.

Louis Leakey and his ax

Leakey discoveries were a family business. Here in 1960 Louis, Mary and 11-year-old Philip excavated a site near the Olduvai Gorge where the first humans lived two million years ago.
Leakey's discoveries were a family business. Here in 1960 Louis, Mary, and 11-year-old Philip excavated a site near the Olduvai Gorge where the first humans lived two million years ago.

On the second expedition, John Solomon, the team's geologist, found such a hand ax in 1929 at the site called Kariandusi. He wasn't sure what he found was a hand ax, but Louis made the correct diagnosis as always. He sent Solomon and a student to find more of these and they did. In those days, there was no method for dating the geological layer where fossils and ancient man-made remains were found.

Geologists were making predictive conclusions by measuring the age of such things and the depth of the surrounding sediments that were supposed to accumulate at a constant rate. Using this measurement, Louis estimated the hand axes to be at least 50,000 years old. Later, more precise dating tools were used, and scientists found that hand axes were as old as 500,000 years.

Finding tools in Africa at least as old as those in Europe was thrilling, and Louis had enough funds to make his biggest expedition ever. In 1931 he set out for Olduvai in the Tanganyika District (now Tanzania). In the Rift Valley, the 25 miles (40 km) long Olduvai curves deep along the Serengeti Plateaus. German geologist Hans Reck surveyed the valley in 1913 and found an abundance of extinct mammal bones as well as modern human bones. Reading Reck's report, Louis thought that although Reck did not find any stone tools in the valley, the geologist had overlooked them.

He invited Reck on his expedition. With four vehicles and a crew of eighteen people, they traveled overland, following the footsteps of Indian traders who had crossed Nairobi for three days, but the trail ended at some point. They then advanced about five miles (eight kilometers) an hour over two days and finally reached the border of the Olduvai Gorge on the morning of September 27th. A little after dawn the next day, Louis walked on his own across the valley and found a hand ax. The feeling was enravishing. He quickly ran to the camp with an ax in his hand and awakened others to share his joy.

Louis and Mary Leakey's love

Mary Leakey describes her love for fieldwork with the following sentence: "I'd rather be in a tent than in a house."
Mary Leakey describes her love for fieldwork with the following sentence: "I'd rather be in a tent than in a house."

Louis met Mary after his expedition. Mary Nicol, as she was called at the time, was a young artist and a promising anthropologist. Louis was married, had a daughter, his wife was pregnant, and was truly broke. He had income from anthropology and his lectures at St John and felt he could get some funding with his popular book Adam's Ancestors in which he described his discoveries. He needed someone to make drawings showing the stone tools, and a friend introduced him to Mary at a dinner party.

The daughter of a landscape painter, Mary grew up traveling in Italy, Switzerland, and France. Like Louis, she was struck by archeology as a child. A French archaeologist guided her and her father through the rooms of the prehistoric Pech Merle Cave with murals and allowed them to search for stone tools in the excavated deposits. This trip had lit a fire in her heart. "After that, I really never wanted to do anything else," she said.

Mary was also not properly educated. After the sudden death of her father, her mother sent her to a convent school but managed to be expelled from school by pretending (she had put soap in his mouth) and caused an explosion in the chemistry class. “The explosion was very loud. Quite a lot of nuns came running, which will have been good for some of them," she said about the incident. She then attended archeology and geology lectures at University College London and the London Museum and volunteered many excavations.

At the age of 20, she was an unconventional, artistic, playful glider pilot with a passion for French cigarettes. Whether she told all this to Louis at the first meal is unknown, but they found each other very attractive and soon fell madly in love.

Louis invited her on his fourth (and final) East African archaeological expedition. He was returning to Olduvai in January 1935. This time they followed a new route, the long, muddy road to the summit of the Ngorongoro Crater and then the dark, narrow gully lines. There were herds of animals, elephants, zebras, rhinos, and buffaloes on the plateaus, and Mary fell in love once again, this time she was struck by Africa.

Mary and Louis Leakey's first discoveries

Louis and Mary Leakey in 1961, looking at the tooth and palate of the Zinj, Australopithecus boisei fossil.
Louis and Mary Leakey in 1961, looking at the tooth and palate of the Zinj, Australopithecus boisei fossil.

Together, Louis and Mary were roaming the gully, collecting stone tools and well-preserved fossils of ancient, extinct animals. They found numerous hand axes and more primitive tools that they later called the Oldowan culture (now known to be 2 million years old, the oldest man-made objects in the world.) But they could only find two bone fragments from the first human skull.

It took another 21 years before Louis was right about human origins. During this time he was divorced from his wife, married Mary, and had four children, three boys, and one girl, but their daughter died in infancy. They settled in Nairobi, and Louis became the director of the museum where he first encountered his mentor, Loveridge. They spent all their spare time and every penny, searching for bones and stones at sites in Kenya and Tanzania.

Sometimes they found surprising things. In 1942, in the Olorgesailie of the Rift Valley in southern Nairobi, they found a path literally paved with hand axes, as if the first humans once owned a factory to produce them. In 1948, on Rusinga Island in Lake Victoria, Mary discovered the skull and facial bones of an ancient but well-preserved 20 million-year-old monkey, the Proconsul; It was the first such monkey face to be discovered.

They found these fossils with the financial support of a London-based American businessman, Charles Boise. The businessman continued to provide them with small funds for expeditions, and in 1959, in Olduvai, finally the financial support and the couple's perseverance paid off. Mary Leakey had made the discovery again. She had gone out alone while Louis was lying ill in the camp and she slowly began to stroll down the rocky slope at the bottom of the gully. Around 11 o'clock, she noticed a piece of bone that sticks out of the ground rather than just standing on the surface. It was looking like a piece of skull. She carefully brushed the soil above it and saw two large teeth on the jawbone. She immediately jumped into the Land Rover and drove frantically towards the camp.

"I found it. I found it. I found it" she was shouting. "What did you find?" Louis asked. "Our man. The man we were looking for. Come immediately, I found its teeth!" she answered. Louis quickly recovered and the two of them went to the area together. Mary was right: they finally found the man they were looking for. Louis first named the skull Zinjanthropus, after the East African word "man". But it was later classified as a hefty form of the hominin Australopithecus found in South Africa. Mary and Louis simply called him "Dear Boy."

Famous fossil hunter family

Richard Leakey continued his parents' fossil hunt and found many hominins in Lake Turkana, Kenya.
Richard Leakey continued his parents' fossil hunt and found many hominins in Lake Turkana, Kenya.

After the Dear Boy, Louis Leakey and Mary Leakey became famous. With new dating techniques, geochronologists were finally able to determine the age of the fossils at Olduvai. It proved to be "very, very, very old," as one of the Dear Boy's scientists told Louis. In fact, the skull was 1.75 million years old; It was a history that shook the world, tripling the initial assumption. The discovery made headlines around the world and sparked an anthropological rush to East Africa by scientists in an attempt to make a claim. The American paleoanthropologist Clark Howell, a colleague of the Leakeys said that the discovery of Zinj started the era of scientific research into human evolution.

Leakeys started full-time excavations in Olduvai with funding from the National Geographic Society. Mary led these excavations, assembling a team of Kamba workers, many of whom would be famous fossil hunters in their own right. Excavations were often family business; Louis, Mary, and their sons Jonathan, Richard, and Philip worked together. It was Jonathan who first found the bone fragments of the new human ancestor. Homo habilis was the hominid that Louis and Mary believed to has made the oldest, most primitive tools in the carving.

From the very beginning, Homo habilis has been the subject of debate. Being an organism different from the Dear Boy would mean that the two hominin species – the first upright, bipedal human – lived on the African savannah at the same time. Louis argued that this possibility was very significant; By looking at other animals, it could be seen that a large number of antelope and primate variants lived together. But most contemporary scientists strongly criticized this branched family idea; they expected a long and straight human line, but it was never going to be the case.

3 million-year-old footprint

Mary Leakley's most extraordinary discovery: 3 million-year-old footprint series of the first hominins in Laetoli, Tanzania.
Mary Leakey's most extraordinary discovery:
3 million-year-old footprint series of the first
hominins in Laetoli, Tanzania.

Then came the sought proof. Leakey's middle son, Richard, went on his hominin hunt expedition around Lake Turkana in Kenya. Here they found the same footprints; Two different hominin species lived side by side, one with thicker bones and the other with a larger brain but slender bones. "They won't believe you." That's what Louis said when Richard gave him the Homo habilis skull.

But over time they believed. Today paleoanthropologists draw many different human lineages, and they are all very branched. Louis Leakey died of a heart attack in 1972, a week after seeing Richard's homo habilis skull. He was 69 years old. Mary Leakey continued her excavations at Olduvai. His team unearthed many fossils, thousands of stone tools. He mapped all of them in great detail, creating an almost 2 million-year-old record of the animal and human habitats that nestled the gully.

In 1974 he turned his attention to another area, Laetoli, where fossils were found older than Olduvai. This is where one of the team members spotted a very old set of footprints in 1978. These were the footprints left by three people walking in the rain when a nearby volcano erupted three million years ago. When she revealed one of the finest footprints, Mary sat back and looked at the beauty. She lit a cigar and said, "This is really a piece to be placed over the fireplace."

She was 65 years old when she made this discovery. She continued her research in Laetoli and Olduvai until the late 1980s. When she died in 1996, Mary Leakey was the world's most famous female archaeologist. Mary and Louis Leakey had achieved the goal they set before they set out for the expedition. So they brought the evidence that the first ancient humans evolved in Africa. Like all great scientists, they have proven wrong the old ideas and the old ways of thinking, with stones and bones.