Attempto! 02/2023: Pieces of the Evolution Puzzle

In today’s linked-in world, Internet search engines, social media and AI seem to put vast amounts of knowledge at our fingertips. Yet we know little about the origins of our early human ancestors and how they spread and settled around the world. In her research project FIRST STEPS, Palaeoanthropologist Katerina Harvati is adopting a new approach, combining new technologies with conventional analysis, seeking new sites and re-examining old finds in her search for evidence of prehistoric Homo sapiens in Southern and Southeastern Europe. Her work provides valuable new information about the migration and lifestyle of our early ancestors.

FIRST STEPS is funded by the European Research Council (ERC) for five years. In the project, the Tübingen researcher is working closely with Stefano Benazzi from the University of Bologna and his lab team. Researchers from Greece and the central Balkans are also involved. “The University of Tübingen has a strong tradition in human  evolutionary studies and Palaeolithic archaeology,” says Harvati. The project is the most recent in a series of large-scale projects that she and her team have conducted over the last ten years, progressively building up what we know about early humans in Europe.

Harvati’s previous ERC-funded projects focused on Southeastern Europe and specifically on Greece. The region played a central role in human migration and survival during the Ice Ages. “The climate and environment would have been very friendly, not only to plants and animals but also to human populations,” she explains.

At the same time, Southeastern Europe is part of a corridor for migration between Europe, the Near East and Africa, as well as Asia, making it an important stop on any migration path, according to Harvati. Yet she says this significance went unrecognized for many years: “We have very little data. The paradox here is that until recently, and partly because of historical research biases, a very important biogeographical region at the crossroads of three continents remained largely unexplored in terms of Palaeolithic archaeology and human evolution.”

The researcher’s projects have focused on very early prehistory, revisiting existing collections of early human remains that may have been neglected in the past, and incorporating them into a larger comparative framework. While re-examining some fossil finds from southern Greece, Harvati and her team made a sensational discovery – that Homo sapiens had been present in Europe more than 210,000 years ago. It challenged the belief that Neanderthals were the only human species in Europe at that time. The study was published in the scientific journal Nature, giving rise to the FIRST STEPS project.

The discovery prompted the team to wonder what else had been missed, as findings may have been overlooked because they were at odds with current orthodoxy. “We wondered if we were missing evidence because we had a completely different framework into which it didn’t fit,” says Harvati. In the search for more evidence, the team started to carry out systematic fieldwork at Palaeolithic sites in Greece, Bosnia and Italy. “Our collaborations in the central Balkans and Italy now enable us to make comparisons across a broader region,” Harvati explains.

When it comes to this kind of very early human history, the little existing material is usually in a poor state of preservation. “The more fragmented and distorted a find is, the more difficult the analysis is – so it needs to be corrected as far as possible,” Harvati says. In addition to more familiar dating and analytical tools, the team uses a wide range of state-of-the-art technical resources.

“In studying the fossil record, we use virtual anthropology techniques and CT- and micro-CT scanning to try to correct distortions and broken parts,” Harvati notes. “For example, we employed virtual reconstruction based on CT scanning for the Apidima 2 Neanderthal from Southern Greece, which was distorted and broken. We were able to virtually dissect each bone fragment from the CT scan, remove sediment from cracks and put the bone fragments in their original position.” The team also managed to mirror-image cranial parts that were missing on one side from the better-preserved other side. In this way it ended up with a much more complete cranium, which was then used in their statistical analyses.

“But sometimes fossils are too small even for this,” Harvati warns. For example, the broken piece of a fossil upper jaw of a child from the El Aliya site in North Africa: “Here we developed methods to help analyse this small piece. We were able to analyse its 3-D shape in a comparative context and ascertain that it was from an early modern human.”

When it comes to artefacts, the team looks for clues as to the materials used, how objects were made, and for tell-tale signs of wear and tear. “For stone tool industries, we employ traditional lithic and production analysis, but we’re also interested in how these tools were used,” Harvati explains. What the researchers discover can end up redrawing the timelines of technology development. “Recently my colleagues in Italy identified possible evidence suggesting very early use of bow and arrows, which we didn’t think happened until later in the Palaeolithic.”

Input from many disciplines

Harvati stresses that results like this depend on modern palaeoanthropology’s interdisciplinary approach. “A team in the field includes all kinds of specialists, from geologists to archaeologists to palaeontologists and zoologists, even botanists,” she says.

FIRST STEPS is expecting to gather important information from an ongoing excavation at Apidima in Greece. “It’s an extremely challenging site, located on a cliff and only accessible by water,” she says. “We have climbing experts there to support us.” After its first campaign there in September 2022, a second is planned for September 2023. A first excavation in Bosnia in May 2023 also showed potential for new finds. “This looks like a late Palaeolithic site,” Havarti notes, “it’s too early to tell, but first results are very promising.” The Project still has a long way to go. “Each project generates so many new questions and so much new evidence that the next step becomes clear in the process,” says Harvati. “That’s the beauty of doing science. Unexpected results open up new doors and things that you didn’t imagine were possible before.”

Her team will continue to collaborate with regional colleagues and to think outside the box. “We’re only just starting this regional comparison. We’re talking about migrations, and these early people weren’t limited by our own cultural and state borders, so we can’t get the full picture from individual data sets.” Yet it is these tiny snapshots of prehistoric life that are needed to create the big picture. Katerina Harvati is looking forward to finding more pieces in this puzzle left by our early ancestors.

Text: Chris Cordy