HEAVYWEIGHT: The fossil, classified as Loxondonta adaurora, weighed two tonnes. It had to be reinforced by a plaster of Paris jacket, rolled over onto a steel frame and strapped in before being raised from the ground
In 2016, Apollo Longaye, a Dassanach man from the Lake Turkana region of northern Kenya, came across a fossil. As a trained fossil hunter and preparator with the Turkana Basin Institute (TBI), Longaye realised that it was quite a find.
After a week of excavation, Longaye and his colleagues unearthed the entire skull of an elephant species that lived four million years ago.
“This skull is unique in that it is complete, with a well-preserved dentition that will provide useful and informative comparative material,” said Dr Louise Leakey, who supervised the excavation.
The fossil, classified as Loxondonta adaurora, weighed two tonnes. It had to be reinforced by a plaster of Paris jacket, rolled over onto a steel frame and strapped in before being raised from the ground.
“We erected a jig to lift it with a chain block high enough to drive a car beneath it and lower it into the back of a pickup truck to transport it back to TBI in Ileret,” said Dr Leakey. The process took a whole day.
Several preparators from the TBI Ileret field station and the National Museums of Kenya (NMK), were involved in cleaning the skull using hardeners and pressurised air drills.
Visiting scientists Steve Jabo, a top vertebrate preparator with the Smithsonian Institute in the US, and Dr Bill Sanders of the University of Michigan, oversaw the construction of a supporting cradle so that the huge, fragile fossil could be rolled over for cleaning and 3D scanning.
TBI is a scientific research centre established by paleoanthropologists Richard, Meave and Louise Leakey. There are two field stations on the east and west shores of Lake Turkana, with the academic centre located at the University of Stony Brook in New York.
The excavation was carried out by the Koobi Fora Research Project, led by Meave and Louise Leakey and supported by the National Geographic Society. Loxodonta adaurora is an ancestor of the modern elephant Loxodonta africana. L.adaurora lived in the Pliocene era, about 4.5 million years ago, and was much larger than today’s elephants.
Over the past 60 million years, several species of now-extinct proboscideans lived in Africa, in ranges that overlapped because some were browsers and others were grazers.
L. adaurora was a ground grazer, suggesting that in the Pliocene epoch the Turkana region had more grass and bushland, and that the level of the lake was higher. The Asian elephant and extinct woolly mammoths are descended from an African ancestor that emigrated to Eurasia about 3.5 million years ago.
Habitat change
Many habitats in Africa have changed from dense woodland and forest to drier, more open landscapes. Adapting to the changing environments, especially in the structure of their teeth, was crucial for the long-term existence of ancient African elephants.
What survives today is a proboscidean adapted both to grazing and browsing in a wide range of habitats. Before this find, the last major elephant fossil discovery was near the Koobi Fora Museum inside the Sibiloi National Park.
In 1974, scientists from the NMK excavated the almost complete skeleton of a two million-year old extinct elephant called Elephas recki, which is related to the modern Asian elephant, Elephas maximus.
The Koobi Fora skeleton belongs to a male elephant about 40 years old, over four metres tall and 12 tonnes in weight, twice the size of the average elephant today. This remote site is open to visitors and attracts adventure-loving tourists as well as researchers.
“Plans are underway, in collaboration with the county of Marsabit, to further develop Koobi Fora as a research camp that can be used by education institutions,” said Dr Purity Kiura, the director of museum sites and monuments at NMK.
Despite these and other discoveries of ancient African elephants, gaps remain in the fossil records that can only be filled by finding more fossils. Dr Leakey says, “We must have boots, and eyes on the ground to spot part of a fossil that is beginning to be eroded from a hill side.”
The elephant skull and other proboscidean fossils from the Turkana Basin are being studied by Dr Sanders and the results will be published soon in a scientific journal.