An international team of researchers from the United States and Israel has found that deforestation combined with climate change will threaten 84 percent of lizard species living across North America. Experts say similar patterns may affect reptiles in other regions as well. The findings appear in Nature Climate Change, a leading scientific journal, and reflect growing concerns about how habitat loss and warming temperatures interact to shape wildlife futures.
Projecting into the latter part of this century, the study concludes that the populations of roughly 18 percent of lizard species could decline significantly over the next eight decades. The trend points to a future where many lizards experience smaller ranges, squeezed by hotter days and the shrinking availability of suitable microhabitats.
Lizards are ectotherms, meaning their body temperature tracks the environment rather than being regulated internally. Unlike mammals, they have only limited strategies to balance heat gain and loss. Tree-dwelling lizards often perch on trunks to soak up sun, yet as the ground grows hotter they retreat to higher elevations or seek shade, maximizing thermal safety whenever possible.
To understand regional impacts, the researchers modeled lizard habitats across diverse North American climate zones. The simulations indicate that ongoing tree loss could shorten daily active time by about a third by the end of the century, reducing opportunities for foraging, mating, and escaping predators. When trees vanish, the cooling shade they provide disappears as well, further stressing thermally sensitive species.
Without the shelter and microclimates created by vegetation, lizards may be forced to hide beneath rocks or to retreat into cooler crevices, increasing the risk of predation and affecting overall species persistence. The study underscores that the heat stress already tied to warming temperatures is likely to be amplified in areas with dense canopy loss, accelerating declines for temperature-sensitive lizards.
The effects are expected to be strongest in warmer regions, where future summers could be too hot for lizards to remain active on land for extended periods. In these places, even small increases in temperature or losses of shade can have outsized consequences for daily activity patterns and reproductive success. The researchers emphasize that adapting to rapid climate shifts will be harder for species with narrow thermal tolerances and limited mobility to track favorable conditions geographically.
Previous work highlights a grim forecast for Mexican lizard populations. By 2080, about 54 percent of species in that country could face extinction risk as they struggle to adapt to faster-than-average warming. The combination of habitat loss and climate stress creates a challenging environment where recovery would require stable habitat patches, cooler microhabitats, and reduced burn or drought pressures that threaten lizard communities. These dynamics resonate beyond North America, as similar climate-habitat interactions are observed in other continents, suggesting a broad ripple effect on reptile diversity according to Nature Climate Change findings.
Beyond the immediate ecological costs, shifts in lizard communities can cascade through ecosystems, affecting insect populations, plant pollination networks, and predator-prey relationships. The study’s authors call for integrated conservation strategies that protect mature trees, maintain habitat connectivity, and support regional climate resilience. By prioritizing land management practices that preserve shade and microhabitats, policymakers and land managers can help buffer sensitive species against warming and habitat fragmentation. The broader message is clear: safeguarding thermal refuges is essential to sustaining reptile biodiversity in a warming world.
Ultimately, the research underscores a stark reality: the path to preserving lizard diversity depends on coordinated actions combining habitat protection, climate mitigation, and adaptive conservation planning. As scientists continue to refine models and monitor populations, the emphasis remains on practical steps that can reduce heat stress and maintain ecological balance for these cold-blooded vertebrates. The work adds to a growing body of evidence that climate change and deforestation are not isolated threats; together they reshape the very habitat fabric that supports life across North America and beyond.
In asking how dinosaurs managed to dominate Earth for 160 million years, some researchers note that enduring success came from thriving in varied climates and evolving resilience to environmental change. Today’s lizards face a different kind of test, one that requires human action to ensure they can endure a hotter, tree-poor landscape and continue to play their part in the web of life.