Lizards living in cities have genetically adapted to survive in urban environments, according to a new study. Researchers from New York University (NYU) have found that lizards living in different cities have a parallel genomic marker when compared to neighboring forest lizards. This marks the first time that parallel physical differences and genomic signatures have been found in urban lizards as compared to their counterparts living in forests.
The study, published in the Proceedings of the National Academy of Sciences (PNAS), analyzed 96 Anolis cristatellus lizards, comparing the genetic makeup of forest-dwellers to those living in Puerto Rico’s capital, San Juan, as well as the northern city of Arecibo and western city of Mayaguez. The Anolis cristatellus lizard, also known as the Puerto Rican crested anole, is commonly found in both urban and forested areas of Puerto Rico.
Scientists found that 33 genes within the lizard genome were repeatedly associated with urbanization and the lizards’ physical differences appeared to be mirrored at the genomic level. The changes in these lizards, whose lifespans are roughly 7 years, can occur very quickly, within 30 to 80 generations, enabling them to escape from predators and survive in urban areas.
“Urbanization impacts roughly two-thirds of the Earth and is expected to continue to intensify. In many ways, cities provide us with natural laboratories for studying adaptive change, as we can compare urban populations with their non-urban counterparts to see how they respond to similar stressors and pressures over short