Deforestation and Urbanization Push Unique Yucatán Lizards Toward Extinction
Lizards, geckos, and iguanas are part of everyday life in Yucatán and can be seen everywhere from inside the home to gardens and archaeological sites like Uxmal.
Unlike other critters who love the heat like cockroaches and scorpions, no variety of lizard in Yucatán is poisonous, and what is even better, they love eating bugs.
But scientists from Mexico’s National University (UNAM) are starting to ring alarm bells and presenting data showing that the heat in major urban areas of the Yucatán Peninsula may be too intense for even these cold-blooded, heat-loving creatures.
Why Lizards Are Highly Vulnerable to Climate Change
Lizards are ectotherms—they rely on their environment to regulate their body heat. Understanding the thermal conditions of their habitat allows scientists to assess how climate change may affect them. Lizards are adapted to warm environments; to feed, move, or reproduce, they need temperatures between 30 and 40 C.
However, global warming could push these creatures beyond their limits. Models developed by the research team suggest that some lizard populations will decline if environmental warming exceeds certain thresholds.
Another factor that puts several species of lizards in Yucatán at risk is that they did not evolve on the peninsula but were introduced through the pet trade (much like several varieties of parrots).
Beyond Heat: The Role of Vegetation
Vegetation not only provides thermoregulation but also offers moisture, shelter, and nesting sites. The vegetation in these areas is crucial, as lizards find shade, protection, and insects to eat among the plants.
“Even though many species seem to tolerate the heat, that does not mean they are in suitable conditions. Excessively high temperatures can reduce the time lizards spend active, limit their ability to find food or shelter, and ultimately affect the survival of their populations,” said researcher Aníbal Díaz.
Human Threats: Urbanization and Deforestation
In addition to climate change, dune lizards face serious threats from human activities such as coastal urbanization, tourist infrastructure development, and deforestation.
“If vegetation is removed, lizards lose shelter, food, and the conditions needed to reproduce. When halophytic plants disappear, their populations decline immediately,” Díaz warned.
Unique Evolutionary Lineages at Stake
Díaz cautioned that the disappearance of these species would not only mean the loss of a form of life but also of irreplaceable evolutionary lineages. These could help explain how reproduction has advanced in certain vertebrates. For example, the species Aspidoscelis (commonly known as whiptail lizards) reproduces through parthenogenesis—females produce offspring without the need for males. As a result, the young are genetically identical to their mothers, creating unique clonal lineages found nowhere else in the world.
Ecology of Lizards: Importance and Call to Action
Despite their small size, lizards play a crucial role in ecological balance. As predators, they help regulate insect populations and, in turn, serve as prey for other animals. Therefore, their conservation is vital.
UNAM researchers further stressed the urgency of preventing dune degradation, preserving its vegetation, and promoting responsible tourism as key measures to maintain the region’s biodiversity.
With information from Gaceta UNAM.
Senior Editor Carlos Rosado van der Gracht, PhD, is a journalist, photographer, and expedition leader. Born in Mérida, Carlos holds degrees from universities in Mexico, Canada, and Norway. Most recently, he earned a doctorate in Heritage Studies in 2026.
