A recent study published in the journal Science reveals that approximately 1.12 million years ago, a significant cooling event in the North Atlantic had profound effects on early human occupation of Europe. This groundbreaking research, conducted by an international team of scientists from the UK, South Korea, and Spain, provides compelling evidence that climate stress altered the course of early human history in Europe.
The Journey of Homo erectus
Homo erectus, an archaic human species, migrated from Africa to central Eurasia around 1.8 million years ago. Over time, they gradually expanded westward towards Europe and eventually reached the Iberian Peninsula about 1.5 million years ago. Initially, these early humans encountered relatively mild climate conditions, allowing them to establish a presence in southern Europe. This is supported by fossil evidence and the discovery of stone tools from this period. However, as glacial cycles intensified from 1.2 million years ago onwards, the duration of early human occupation in Europe remains unclear.
In order to gain a deeper understanding of the environmental conditions experienced by early human species in Europe, the research team combined data from deep ocean sediment cores with advanced climate and habitat models. By analyzing thousands of small plant pollen and temperature-sensitive organic compounds extracted from the sediment core, the scientists unveiled a startling revelation. Approximately 1.127 million years ago, the climate in the eastern North Atlantic and adjacent landmasses underwent a sudden cooling of 7°C.
This dramatic cooling event represents one of the earliest recorded terminal stadials in paleoclimatic history. It occurred during the final phase of a glacial cycle when ice-sheets disintegrated, releasing vast amounts of freshwater into the ocean. Consequently, ocean circulation patterns shifted, and sea ice expanded southward. The impact of these changes was further magnified by the transition of western European vegetation into an inhospitable semi-desert landscape, as evidenced by the pollen data from the ocean sediment core.
To assess how early humans might have responded to this unprecedented climate anomaly, scientists conducted computer simulations using global climate models. By introducing glacial freshwater into the North Atlantic, the researchers were able to reproduce the cooling and drying effects observed over southern Europe during the terminal stadial event. These simulations were then used as input for a human habitat model, which determined the suitability of the environment for early Homo erectus. The results were alarming – vast areas of southern Europe would have become unsuitable for the survival of early human species like Homo erectus.
Despite the relatively short duration of the cooling event (approximately 4,000 years), the absence of stone tools and human remains for the following 200,000 years raises the possibility of a prolonged interruption in European occupation. Europe was eventually repopulated around 900,000 years ago by a group known as Homo antecessor. Unlike their predecessors, Homo antecessor and its descendants developed greater resilience and adaptability to the increasingly intense glacial conditions in Europe.
A Historical Perspective
This study sheds light on the sensitivity of southern European vegetation and human food resources to temperature changes in the North Atlantic. The findings add to the growing body of evidence that highlights the profound impact of past climate changes on human history. Understanding our past is crucial in comprehending the dynamic and interconnected relationship between climate and human civilization. As we navigate the challenges of modern climate change, the lessons learned from our ancient ancestors can guide us towards a more sustainable future.
The study’s findings provide new insights into the disruptive effects of climate change on early human occupation of Europe. By combining various data sources and advanced modeling techniques, scientists have uncovered a significant cooling event that altered the course of human history. This research serves as a reminder of the intricate relationship between climate and human civilization and highlights the importance of studying our past to inform our actions in the present and shape a more resilient future.