Origins of the species

The sustained and painstaking work of the Leakey family since the 1940s has changed our understanding of human evolution

Last month, on Christmas day, the James Webb Space Telescope was launched into deep space to peer into the origins of the universe. Last week, Richard Leakey, the famous Kenyan paleoanthropologist and conservationist, who spent much of his life researching the origins of the human species in the East African Great Rift Valley, died at his home near Nairobi at the age of 77. He belonged to an extraordinary family of British-Kenyan fossil seekers/analysts who may have contributed, since Charles Darwin, more to our understanding of the origins of Homo sapiens than any other single family in the world. His parents, Louis Leakey and Mary Leakey, each made path-breaking contributions to the field as did Richard’s wife, Meave, brother Jonathan and daughter Louise. It is worth spending a little time to appreciate the enormous contribution of this family to our still evolving knowledge of the origins of Homo sapiens.

Until about the middle of the 20th century, most Western scientists believed that Homo sapiens evolved around 50,000-60,000 years ago in Eurasia. It was the sustained, painstaking work of the Leakey family and a few others from 1940s onwards that placed the origins of man decisively in Africa, with Homo sapiens evolving somewhere between 200,000 and 300,000 years ago from one of the various branches of pre-sapiens hominids (confusingly, also termed hominines) that trace back to the chimpanzee line from which they branched out somewhere between 5 and 7 million years ago.

Illustration: Binay Sinha

Initially, the Leakeys and their teams worked in primitive conditions with primitive tools but they made hugely important discoveries. Working on Rusinga Island in Lake Victoria in 1948, Mary Leakey discovered a skull of Proconsul africanus, long thought to be an ancestor of both apes and hominids, that lived perhaps 25 million years ago. For the next many years they shifted their focus to the 25-mile long Olduvai Gorge in northern Tanzania, not far from the great Ngorongoro extinct volcano crater and the famous national game reserve, which I visited nearly 50 years ago. It was here in 1959 that they discovered the skull of an early hominid, that they called Zinjanthropus, dated to be over 1.7 million years old, which brought them global fame, as well as long-term funding from National Geographic. A few years later their team discovered fossil fragments of another hominid line, the tool-making Homo habilis, dated at around 1.4 million years ago.

In 1960, Louis turned over the directorship of the Olduvai Gorge excavations to Mary and shifted his attention to establishing museums, fund-raising and lecturing. Around this time, convinced of the importance of links between other primates and man, he selected and mentored three, subsequently famous, young researchers, Jane Goodall (chimpanzees), Dian Fossey (gorillas) and Birute Galdikas (orangutans) to undertake pioneering long-term studies of these primates in their natural habitats. Suffering from poor health in his later 60s, Louis passed away in 1972. After his death, Mary continued with her field work and important finds, including the famous footprints at the pre-historic Laetoli archaeological site (25 miles south of Olduvai Gorge), which were the earliest clear evidence of upright walking by a hominid, Australopithecus afarensis, around 3.7 million years ago.

Their middle son, Richard Leakey, after a brief detour as a safari guide, took up the family profession of fossil hunting and analysis with gusto in his early 20s after spotting the promising topology of the shores of Lake Turkana (earlier Lake Rudolf) in northern Kenya from a small plane he was flying. Prominent among the several hundred hominid fossil discoveries of Richard Leakey and his “Hominid gang” in the Turkana Basin were: An almost complete skull (pieced together painstakingly by his wife, Meave, in 1972) of a Homo habilis; another, in 1975, of a Homo erectus; and, in 1984, of an almost complete skeleton of a Homo erectus child dubbed “Turkana Boy”. Leakey maintained that around 3 million years ago three different forms of hominids existed simultaneously in the region, with two of them dying out over time and the third, Homo habilis, evolving into Homo erectus, which he believed to be the direct ancestor of Homo sapiens.

Richard Leakey parlayed his fame and success as a paleoanthropologist into funding and nurturing museums (he headed the Kenyan National Museums for 20 years from 1968) and establishing a robust, multi-disciplinary research infrastructure for work in this field. In 1989 he was appointed head of the Kenya Wildlife Service and cracked down ruthlessly on ivory poachers, making powerful enemies. Later, after surviving a plane crash in which he lost both his legs in 1993, he dabbled, unsuccessfully, in politics before serving for two years as secretary to the cabinet of the Daniel Arap Moi government at the turn of the century. He spent his final years as a professor in Stony Brook University in New York, heading the Turkana Basin Institute and lecturing widely across the globe.

By some estimates, the collective contribution of fossil discovery and analysis by the Leakey family cumulates to around half the total available fossil evidence relating to human evolution. There are several striking conclusions one can draw from the post-1940 work in this area. First, the origins of man (including various species of hominids) stretch back six million years or more. Second, because the fossil record is, in its nature, still quite fragmentary, our understanding of man’s origins is a work in progress despite the enormous advances of the last few decades. Third, the 300,000-year long history of Homo sapiens is actually a short time span compared to the longevity of various other species, including several lines of hominids. Fourth, it is noteworthy that in recent centuries, the explosive growth of the Homo sapiens population has come at the expense of thousands of other species. Last, and most worrying, sapiens has been the most deadly species not only for others but quite possibly for itself, as the cumulative consequences of its actions pave the way towards the Sixth Extinction.

The writer is Honorary Professor at ICRIER and former Chief Economic Adviser to the Government of India. Views are personal