Unveiling the Hidden Diversity of Atacama Geckos
Beneath the sun-scorched skies of Chile’s Atacama Desert, a tiny reptile is reshaping our understanding of biodiversity. Using cutting-edge genomic tools, a team led by Kamryn Carter of the University of Wollongong (UOW) has revealed that the Garthia geckos, also known as Chilean marked geckos, comprise far more species than previously thought. The once-simple story of a single gecko species in the driest desert on Earth has evolved into a complex tale of cryptic diversity and deep evolutionary history.
From Morphology to Genomics: Rewriting a Biogeographic Tale
Historically, scientists identified two species of Garthia geckos based on outward appearance. However, a closer look at color patterns suggested these geckos looked alike across wide stretches of habitat, hinting at a single species. Carter and her collaborators turned to genomics to test that assumption. By analyzing mitochondrial and nuclear DNA across populations, they reconstructed the geckos’ evolutionary history and mapped genetic differences with unprecedented resolution.
Two species, in particular, stand out: Garthia gaudiachaudii and Garthia penai. While visually nearly indistinguishable, genetic data place them on separate evolutionary trajectories, with divergence dating back roughly 20 million years. The researchers’ work demonstrates that surface similarities can mask a rich, enduring diversity lurking beneath the skin of a desert-dwelling lineage.
The Scale of Hidden Diversity
The genomic analyses suggest at least two distinct species exist within the studied range, and possibly as many as 11 cryptic species. This staggering hidden diversity means the Atacama’s gecko fauna is far richer than previously imagined, a finding that carries important implications for conservation amid climate change and habitat loss.
Dr. Damien Esquerré, a co-author, emphasizes that traditional methods often overlook cryptic species. “South America hosts a wealth of threatened life, yet many regions, including the Atacama, remain underexplored at the genomic level,” he notes. The study’s use of modern genomic tools allows researchers to peek into evolutionary dynamics that give these geckos their resilience in one of the planet’s harshest environments.
Implications for Conservation and Climate Resilience
Understanding how many distinct species exist—and how they have adapted over millions of years—helps scientists predict how each lineage might respond to future climate shifts. Cryptic diversity can mean that conservation plans designed for a single species may overlook the unique needs of several cryptic relatives. In a region as fragile as the Atacama, where aridity and temperature extremes test the limits of life, preserving genetic diversity is crucial for the long-term survival of these geckos and the ecosystems they inhabit.
What Comes Next in Atacama Genomics
The publication, titled “Hidden diversity in the driest desert on Earth: genomics unveils cryptic diversity in an ancient South American gecko lineage (Phyllodactylidae, Garthia),” appeared in Molecular Phylogenetics and Evolution. The work, led by Kamryn Carter with contributions from Chilean and U.S. researchers, showcases how advanced genomic technologies can illuminate evolution in extreme environments and reshape our understanding of biodiversity hotspots.
As climate change continues to reshape habitats worldwide, studies like this highlight the importance of integrating genomics into conservation planning. The Atacama’s tiny geckos reveal a big message: in nature’s most inhospitable places, genetic diversity may be more abundant—and more ancient—than we ever imagined.
About the Research
Hidden diversity in the driest desert on Earth: genomics unveils cryptic diversity in an ancient South American gecko lineage (Phyllodactylidae, Garthia) was authored by Kamryn Carter, Claudio Reyes-Olivares, Jonathan Eubanks, Hayden Hanna, Stuart Nielsen, and Damien Esquerré. The study underscores how modern genomic methods illuminate evolution and biodiversity in one of the Earth’s most extreme environments.
