“Humans are African mammals. We need to understand biology in Africa. Africa has so many more lessons to offer us. We have to take human evolution more seriously and take Africa more seriously. We are best placed to study our own origins and the rest of the world should be coming to Africa. We need to highlight the importance of the Mother Continent,” said Jonathan Kingdon of the Zoology Department at Oxford University.
Kingdon grew up in Tanzania where he was born in 1935. He taught for 15 years at Makerere University in Uganda and is currently research associate in the Department of Zoology at Oxford University. His work bridges the arts and sciences, ranging from draftsmanship, sculpture and painting to the writing of scientific books on zoology, anthropology and biogeography. He is probably best known for his seven-volume magnum opus, East African Mammals; an atlas of evolution in Africa (1971 – 1982) and The Kingdon Field Guide to African Mammals (1997, 2015).
“Every organism has a place, time and climate of origin,” he said. “Kangaroos originated in Australia about 16 million years ago, penguins in Antartica about 70 million years ago and polar bears in the Arctic about 200 thousand years ago, humans evolved in Africa over a period of some six or eight million years.”
Each were carefully adapted to the geography and climate they inhabited and matched the behaviours that would ensure their survival. “Behaviour drives and determines morphology, not the other way round,” said Kingdon. “This is the deep insight that biology offers to the world. It puts a special value on life itself, on each plant and animal.”
He described his STIAS seminar as being in three parts – a discussion of humans as an African endemic in Deep Time, a focus on South Africa as a ‘Refugium’ and the region of origin for the genus Homo, and a discussion of ‘race’, its misrepresentations and the adaptive origins of skin pigmentation.
Suggesting that the beginning of ‘The Modern World’ was approximately 66 million years ago when a 10km-wide comet hit the Yucután Peninsula in the Gulf of Mexico leading to the extinction of the dinosaurs and the beginning of the age of mammals, Kingdon said: “Comet Chicxulub governs our history and existence. Without the comet dinosaurs would still dominate. It’s the day the modern world began”.
Although the dinosaurs and most mammals and plants were destroyed, the Cape in particular he argues, offered a refuge where some plants and mammals survived – a sequence of events and chance which eventually had a bearing on the evolution of Homo sapiens.
His current project explores how those survivors contributed to current biodiversity in Africa. And to do so he aims to reconstruct the relative roles, advantages and consequences of these sources of evolutionary innovation and to highlight the complex, interesting and diagnostic histories of contemporary living species.
“I’m asking to what degree Africa’s repopulation comes from the life-forms saved in the Cape following Chicxulub,” he explained.
He pointed to some examples – proteas, South Africa’s national flower and a primitive plant family that predates 66 million years. The Spookpadda (Heleophryne rosei) is a frog species endemic to Table Mountain, its lineage, little differing from the living frog, also predates the comet and exists in unmodified form; as well as the beautiful Cape Moraeas.
Kingdon explained that these plants and others like them survived because it was autumn and they were preparing for winter – this and the distance from the comet’s impact meant they were in a favourable position to survive the catastrophe.
“We live in a world of animals and plants that predate us by hundreds of millions of years – we have a duty not to exterminate them,” he added.
The ability to take advantage of a dinosaur-free world and successive combinations of place and space led to the evolution of primates and their eventual evolution into modern man.
Enter our nearest cousins shuttling between continents
“If you make friends with a primate you know you are in the company of a cousin,” said Kingdon.
“The primates evolved in South-East Asia which was furthest from the comet’s impact,” he explained. “We know the higher primate lineage entered Africa from Asia about 40 million years ago and some 20 million years later one or more descendants found their way back to Eurasia where they were hugely successful – their modern iterations being Orang Utans and Gibbons.”
“Yet again, a Eurasian Dryopithecine ape found its way back into Africa about 10 million years ago to found the lineage that culminated in humans and African apes. What I call ‘Humpanzees’ diverged into western chimpanzees and eastern hominins and eventually into Homo. There is evidence that our genus, Homo evolved about three million years ago, specifically in South Africa.”
According the Kingdon, a probable reason for the chimpanzee/human divergence was climate change and the persistence of an arid corridor between the forests of central and western Africa and those of the East African coast. A habitat that stretched for 4000km linking Somalia to the Cape in a long, thin line. Resources in this area were predominantly terrestrial which led to the development of Ground Apes, Ardipithecus, which expanded along this north/south axis. Different hinterlands generated different species across changing latitudes and habitats.
“Ground foraging gave prominence to hands. Hands and fingers became the interface with the substrate,” he explained. “And whereas gorilla hands are made to take weight, human hands are free to do other tasks. It was hands that drove getting up and walking on two not four legs. Bipedalism emerged from ground foraging.”
This led to the emergence of “Southern Man-Apes” or Australopithecus of which Australopithecus Prometheus or Little Foot (discovered in the Sterkfontein caves in 1994 and dated to over three million years ago) and Homo naledi discovered in 2013 in the Cradle of Humankind about 50km northwest of Johannesburg, and dating to about 300 000 years ago, are the most famous.
“And thus began the human lineage,” said Kingdon.
Why are humans so different?
But if Homo sapiens evolved in Africa why are humans so varied and why are so many less than black?
“Many stories of origin equate skin colour with ’race’ and colonial relationships were warped by the poisoned chalice of race,” said Kingdon. “Questions of race have been hugely distorted in history by whole swathes of humans in search of symbolism to enslave and treat as ‘other’.”
“Every animal has colour,” he said. “Changing colour has meaning but is adaptive – it allows an animal to survive.”
Using the example of the Lesser Sengis or elephant shrew he pointed out that their fur colour matches soil colour because their natural predator, hawks “have sharp eyes – the more they match the surrounding soil the better they survive”.
Similarly with humans – human skin evolved to cope with environment, technology and behaviour.
Thin skin with diminished pigmentation allowed sun-starved skins in colder climates to still produce vitamin D and thus avoid rickets, while thicker, heavily pigmented skin and curly hair helped to protect against solar radiation in warmer areas of the world.
But why does Kingdon think all of this is important?
“This work concerns the ultimate questions about understanding our own existence. Too many human beings lack curiosity about this. It’s odd that that we are so unserious about our own origins,” he said. “Natural processes dominate every aspect of our biology and history. I’m trying to enhance the perception of our existence in Deep Time. You can only understand biology in deep time and you can’t understand anything without evolution.”
In response to a plea for a more personal perspective he confessed: “My ideal is a united Africa. We have been victims of the most atrocious and disgusting exploitation. It will only stop if we are united. We are all the children of Eve. Africa offers huge sources of illumination about the past and the future.”
“It’s about whether we respect curiosity and allow it to take us down paths deep in the past or into the future. We should allow it to take us where it will,” he concluded.
Michelle Galloway: Part-time media officer at STIAS
Photograph: Noloyiso Mtembu