Researchers amazed by UAE’s luminescent geckos

Scientists have made a groundbreaking discovery regarding the illuminating ability of desert-dwelling geckos in the UAE. These nocturnal creatures have been found to exhibit prominent skin fluorescence, a trait previously only observed in geckos in the Namib desert of Africa.

During a field trip to a desert area in Sharjah, researchers stumbled upon this dazzling phenomenon in June 2022. Subsequent observations in Al Ula, Saudi Arabia, Nizwa, Oman, and a return to Sharjah in June revealed that three species of geckos in the region possess this unique ability.

The fluorescence is believed to aid these reptiles in identifying members of the same species, potentially assisting in mating behaviors. Dr. Bernat Burriel-Carranza, from the Museum of Natural Sciences of Barcelona and the lead author of the study, expressed surprise at the discovery, noting the bright neon-green coloration reminiscent of Namibian desert geckos.

Two species, the dune sand gecko (Stenodactylus doriae) and the Arabian web-footed sand gecko (Trigonodactylus arabicus), displayed bright fluorescence around their eyes and flanks. The eastern sand gecko (S. leptocosymbotes) also exhibited fluorescence, albeit less prominently. A fourth species, Slevin’s sand gecko (S. slevini), showed minimal fluorescence around its eyes.

The ability to fluoresce is only visible to humans under UV light, but geckos likely perceive it naturally as their eyes detect light beyond the human visible spectrum. This trait has been observed in six gecko species previously, with the nocturnal web-footed gecko in the Namib desert being the only other known fluorescing species.

The skin fluorescence in Arabian geckos is believed to have evolved independently from their Namibian counterparts. This mechanism is thought to facilitate communication in desert environments, where these geckos are commonly found.

Interestingly, the fluorescence is predominantly located on the lower parts of the geckos’ bodies, possibly to minimize visibility to predators. Prof. Salvador Carranza, from the Institute of Evolutionary Biology at CSIC-Pompeu Fabra University in Barcelona, explained that this positioning may be a strategic trade-off between communication and predator avoidance.

Photographs from the study also revealed bone fluorescence in the tibia of the dune sand gecko, indicating a unique aspect of these geckos’ biology. While the exact mechanism behind the fluorescence is not confirmed, it is believed to involve iridophores, specialized cells that emit light.

Despite their remarkable traits, the geckos in Arabia are classified as being of “least concern” by conservation organizations, indicating that they are not currently threatened. These geckos are distinct from the common house geckos found in urban areas and are prevalent across desert regions in Saudi Arabia, Oman, and the UAE.

This groundbreaking research sheds new light on the fascinating adaptations of desert geckos and highlights the importance of studying biodiversity in unique ecosystems. The discovery of skin fluorescence in these geckos opens up new avenues for understanding their behavior and evolutionary history in arid environments.

As scientists continue to unravel the mysteries of these glowing geckos, the world awaits further insights into the remarkable adaptations of these nocturnal creatures in the Arabian deserts.