A plume of heated rock rising from deep within the Earth's mantle uplifted the Arabian Peninsula around 20 million years ago, creating a land bridge between Africa and Asia. This event ended Africa's 75-million-year isolation and significantly impacted animal migration and evolution.
The uplift, driven by mantle convection, closed the Tethys Sea earlier than expected, splitting it into the Mediterranean and Arabian Seas. This land bridge allowed animals like elephants, giraffes, and cheetahs to migrate between continents, diversifying their habitats and driving evolutionary shifts. Eivind Straume noted that the timing of the land bridge was critical for primate migration, influencing the lineages that survived and evolved.
The formation of the Arabian land bridge also dramatically altered ocean currents and climate patterns. The closure of the Tethys Sea led to warmer ocean temperatures, increased seasonal temperature ranges, and aridification from North Africa to Central Asia, contributing to the Sahara Desert's formation. Thorsten Becker emphasized the study's relevance to understanding the connections between Earth's processes, life, and tectonics.