Digging around in dirt all day may not be considered the best job by far, but when the end result is finding a fossilised bone dating back millions of years, it can’t get more exciting for paleontologist Pippa Haarhoff, who manages the West Coast Fossil Park in Langebaan.
For Haarhoff and her co-researchers, their finds hold clues to reconstructing, in as much detail as possible, “what exactly happened” millions of years ago to make this part of the West Coast an “amazing burial site” for more than 200 different species of fossil animals.
The site is outside Langebaan on the R45 and is known scientifically as the Langebaanweg fossil site. It was home to a phosphate mine until operations ceased in 1993.
With the help of Iziko SA Museum, South African Heritage Resources (SAHRA) and BhpBilliton, the park was declared a national heritage site and is today run as a trust.
Over the years a variety of fossils have been discovered, some dating back as far as five to 10 million years ago.
Haarhoff says studying the bones and teeth gives clues of how the animals died and the circumstances of the burial process that led to their preservation over millions of years.
“For example, we have found a seal bone that has porcupine chew marks on it,” she says.
“So it is possible that this particular bone was dragged by the porcupine into its den for chewing on and the bone was buried in the den at a later date. We even found tiny gnaw marks on bones from little rats and mice”.
Some of the bigger fossils, like the Sivathere, which weighed about 2 000kg, have hyena chew marks and tooth marks on them.
Haarhoff explains that they also found other signs of damage on the bones, including fracturing, splintering, scratching and exfoliation from trampling and weathering processes.
“This helps determine how long the carcasses and skeletons were exposed on the surface before their final burial, and what climatic conditions existed at the time.”
The Sivathere (Sivatherium hendeyi) is known as a short-necked, long-horned giraffe. This animal was named after the god Shiva and the species name, hendeyi, is named after Dr Brett Hendey, who headed the research at this site for more than 20 years.
A study done at the site by Professor Richard Klein found that at least 517 individual Sivatheres were buried in the area in a catastrophic flood about 5 million years ago.
“Based on the work Hendey and his colleagues did and subsequent ongoing research, there is a suggestion that there has been serious climate change in this region over the last 10 million years,” Haarhoff says.
She says it used to be much warmer than it is today and the climate was more tropical, with four tusked elephants and African bears roaming around.
“There were no human beings then and the big climate change debate today centres on what effect humans are having on the planet. From studies such as these, at the fossil park, we can get a good idea of how climate change operated without humans.
“This fossil site has captured a phase of transition from archaic fauna to the more modern fauna that we are familiar with today. Marine fossils and other geological evidence also indicate a much higher sea level of 30m.”
But running a heritage site while making sure that it operates well can be a challenge when you don’t have enough staff.
Haarhoff says one of the biggest challenges is not having a full-time research team based at the park.
“We have colleagues from different universities and museums all over the world who come and study the fossils, and the excavations at the site are headed up by Roger Smith and Deano Stynder from Iziko SA Museum and UCT respectively.
“But we need staff to sieve and sort the tons of fossils that are dug up,” says Haarhoff.
“The people sorting the fossils need to be trained to recognise the bones of different kinds of animals, such as rodents, frogs, birds, snakes, geckos and so on.”
Haarhoff says they have trained people with limited or no scientific background from the neighbouring towns and Green Village (the old Chemfos Mine village) to work as tour guides, help with the sorting of the fossils and the general administration and maintenance of the park. “But with more funding, there is a good opportunity for more much-needed job creation.
“The knowledge generated from this type of research helps us understand how life on Earth works, and should help us take better care of this planet that supports us,” said Haarhoff.
“We certainly need to do better than we are doing now.”
l The reporter visited the fossil park as part of a field trip organised through the Habitable Planet Workshop.
The 10-day workshop at UCT, attended by scientists and students from across southern Africa, aimed at teaching students a different way of looking at climate change and its effect on the continent.