Recurrent humid phases in Arabia over the past 8 million years.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40205061.
- Also identified by DOI 10.1038/s41586-025-08859-6 and PMC identifier 12018461.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The Saharo-Arabian Desert is one of the largest biogeographical barriers on Earth, impeding dispersals between Africa and Eurasia, including movements of past hominins. Recent research suggests that this barrier has been in place since at least 11 million years ago<sup>1</sup>. In contrast, fossil evidence from the late Miocene epoch and the Pleistocene epoch suggests the episodic presence within the Saharo-Arabian Desert interior of water-dependent fauna (for example, crocodiles, equids, hippopotamids and proboscideans)<sup>2-6</sup>, sustained by rivers and lakes<sup>7,8</sup> that are largely absent from today's arid landscape. Although numerous humid phases occurred in southern Arabia during the past 1.1 million years<sup>9</sup>, little is known about Arabia's palaeoclimate before this time. Here, based on a climatic record from desert speleothems, we show recurrent humid intervals in the central Arabian interior over the past 8 million years. Precipitation during humid intervals decreased and became more variable over time, as the monsoon's influence weakened, coinciding with enhanced Northern Hemisphere polar ice cover during the Pleistocene. Wetter conditions likely facilitated mammalian dispersals between Africa and Eurasia, with Arabia acting as a key crossroads for continental-scale biogeographic exchanges.