The explosive eruption of the Toba supervolcano 74,000 years ago marked a turning point for humanity. A recent study published in
Nature reveals how this catastrophe may have played a key role in dispersing our ancestors out of Africa.
Contrary to the notion that our ancestors migrated only during abundant periods, researchers have discovered that they also moved during dry periods, utilizing "blue highways" formed by seasonal rivers. These new migration routes were highlighted through the analysis of archaeological sites in northwest Ethiopia, where evidence of stone tool usage and food cooking dates back to this period.
An innovative dating method based on cryptotephra - tiny fragments of volcanic glass - has made it possible to correlate archaeological sites with remarkable precision, thus highlighting the importance of our ancestors' behavioral flexibility in the face of major environmental changes.
The study suggests that the climatic challenges posed by the eruption of the Toba supervolcano extended the dry seasons, prompting populations to adapt by consuming more fish. This adaptation and mobility along seasonal waterways could have encouraged humanity's dispersion out of Africa and facilitated its expansion across the world.
Excavations revealing human survival at the time of the Toba supervolcano eruption.
Credit: ODbL v1.0
This research highlights our ancestors' adaptability and offers a new perspective on the migratory routes of early humanity, challenging previous theories limited to periods of environmental prosperity.