It might surprise you to learn that southern Arabia is a global biodiversity hotspot. While the landscape is not the lushest, a high proportion of the vegetation are endemic desert-adapted plants. A new survey, by James Borrell and colleagues, finds evidence for a climate refugium in the Central Oman Desert. The area could be the northernmost remnant of a continuous belt of mesic vegetation formerly ranging from Africa to Asia.

James Borrell said: “Many researchers interested in the diversity and distribution of Northern Hemisphere plants and animals will be familiar with the idea of glacial refugia. In Europe the expansion and recolonization of species after the last glaciation is probably one of the single most important factors influencing plant distributions today. However, these ideas have rarely been demonstrated in the extremely arid environments of the Middle East. Therefore, this study provides a useful corollary to more established European and North American examples.”

“Over broader time scales, it is now increasingly established that areas with long-term climate stability have an important role to play in species evolution. We think this is one of the drivers of the high level of endemism found in the flora of the Central Desert, and in our paper we narrow in on precisely the region that we think has acted as a refugium.”

The desert is not somewhere that leaps to mind when thinking of botanical opportunities. I asked James Borrell what drew him to Oman. He replied: “Many of the international authors on this study have various long-running associations with Oman, having been enthralled by Omani hospitality and culture. I was first involved with a biodiversity survey expedition to Dhofar in 2012, and others have run a diverse array of botanical expeditions.

“It’s true, when I first visited Oman – as a biologist – I also pictured vast empty sand deserts and wondered if there would be enough life to keep me occupied. You only need to sleep out on the sand and in the morning inspect the imprint of hundreds of insect and small mammal tracks to realise these deserts really are full of life!”