In the latest string of research and studies shedding light on the incredibly complex history of human evolution, fossils found in Boxgrove, England have been compared to fossils found at Sima de los Huesos (or the ‘Pit of Bones’) in Spain. The Boxgrove fossils, found in the 1990s, include two fossil teeth and part of a lower leg bone, and were dated to 480,000 years ago. Scientists are attempting to ascertain whether Boxgrove humans and other early human fossils at the Atapuerca archaeological site are the same.
Dating and Linking La Sima and Boxgrove: By the Skin of the Teeth
An ambitious collaboration of British and Spanish archaeologists and scientists have tried to uncover the identity of these humans, publishing their finds in the Journal of Human Evolution . La Sima is one of the world’s richest human fossil sites, with the remains of 30 individuals scraped from the sticky sediments of a 50-foot (15.24 feet) shaft that drops almost vertically.
The hominid remains here have been dated to 430,000 years ago, which is not a great difference in date from Boxgrove. This is why, when La Sima had been uncovered as a site, the fossils here had been called Homo heidelbergensis out of convenience. The results of this study show that it was perhaps an early Neanderthal, based on physical features and DNA analysis .
Meanwhile, Boxgrove in West Sussex also yielded human remains along with sophisticated stone tools . The Boxgrove fossils are linked to the same ancient human species, the Homo heidelbergensis. Thus, trying to piece together the scattered human populations from the Middle Pleistocene has always proved to be a huge challenge, according to a press release by the Natural History Museum, London.
One of hundreds of handaxes found at the Boxgrove site (Midnightblueowl/ CC BY-SA 3.0 )
The riches of the pit at La Sima represent a significant number of skull injuries, which had led to the suggestion that perhaps this was a place of burial. Individuals were killed and then thrown into the pit, according to a report in The Observer . The pit’s riches are without precedent, making them crucial for the fossil record.
Professor Chris Stringer, an expert in human evolution at the Museum and co-author of the study, says, “We’ve got two options. First, suppose the Boxgrove incisors and tibia are from the same population. In that case, they belong to a different population than the sample in Spain because the Boxgrove tibia has more primitive features.”
Four human species are represented here (H. erectus, H. heidelbergensis, H. neanderthalensis, H. sapiens). (© The Trustees of the Natural History Museum , London)
“However, because the Boxgrove incisors were found lower and therefore earlier in the sequence of deposits than the tibia, the other option is that those individuals at Boxgrove represent two different populations. In other words, the incisors at Boxgrove and Sima could represent the same population, but the Boxgrove tibia people are different. So that’s the issue,” he added.
A Loss of Identity: Matching Teeth, Varying Tibias
Professor Stringer further explained that what they were dealing with was a potential ‘loss of identity’ of the early Britons. The chronology of Boxgrove and La Sima represents a potential link that would bind the latter and former. To corroborate, they used 3D imaging and virtual reconstruction analysis at both the sites, to help further the database of fossil teeth and bone morphology across the Middle Pleistocene.
However, with the Boxgrove tibia being in a different shape, and very robust, it suggests a different species of Homo. However, the shin bone and teeth at Boxgrove are from different levels in the excavation – the teeth perhaps from an early Neanderthal population, while the shin bone could be from the Homo heidelbergensis. For this reason, the categorization of the species or species (plural) remains an unresolved mystery.
However, archaeologist Dr. Matthew Pope, from UCL’s Institute of Archaeology, who has been leading the excavations at Boxgrove, stressed that much had already been learned in recent years about the people of Boxgrove. Thus, it cannot be said that they’ve hit a dead end – rather, they’ve vastly expanded pre-existing knowledge about fossils in continental Europe from this epoch.
“We can see where they made their stone tools to butcher animals. From the flakes they were chipping from stones to make handaxes, you can see how these people were working systematically and co-operatively. They were in command of their raw materials. Boxgrove tells us how they worked. What it does not tell us is where they had their homes or what kind of dwellings they had,” he concluded.
Moving forward, Dr. Pope and his colleagues plan to date the sediments and understand how separated in time exactly these layers are. This becomes the most crucial question to answer now.
Top image: Part of the tibia of an early human believed to be Homo heidelbergensis discovered at the Boxgrove archaeological site in West Sussex. Source: © The Trustees of the Natural History Museum , London
By Sahir Pandey