Climate change is impacting the population of one major species before they are even born. Scientists in France have discovered that rising temperatures are causing common lizards to be born with DNA damage. “The most relevant result of the paper is the detection of a very worrying tendency towards shorter telomeres—and thus, faster aging—in populations exposed to the more demanding climatic conditions for the species,” Germán Orizaola, an evolutionary ecologist at the University of Oviedo in Spain who was not involved in the study, tells the Washington Post, adding they are “at higher risk of extinction.” Here’s why, and what “pseudoextinction” means for you and the planet.
Researchers discovered the baby lizards were born with damage to their telomeres—the caps found on the end of each strand of DNA. Telomeres are responsible for protecting the DNA strand, but naturally wear down through the natural aging process, or, as in the case of the lizards, through stress.
According to the findings published in the Proceedings of the National Academy of Sciences, lizards in hotter parts of France were born with shorter telomeres, suggesting the heat is causing accelerated aging damage via climate stressors. “We know human-induced climate change is impacting animals, and the habitats they live in. Climate change can cause accelerated life history like faster body growth and earlier sexual maturation,” says Dr. Nic Rawlence, director of the Otago Palaeogenetics Laboratory.
Researchers are afraid this DNA damage could lead entire species to be wiped out as a result of climate change. “While [faster body growth and earlier sexual maturation] may be a good adaptation in some instances, it now seems it comes at a cost…rapidly eroding telomeres across the generations until a tipping point is reached and extinction is all but guaranteed,” says Dr. Rawlence.
Telomere damage can be passed from generation to generation, which makes it difficult to undo the damage. “Once you are in this circle of events, it’s quite complicated to come back,” says study coauthor Andréaz Dupoué, a biologist at IFREMER, an oceanographic institute in France. “It can become a vicious circle,” which the researchers call an “aging loop.”
Researchers discovered that a lizard population from Mont Caroux, one of the hottest parts of France, has already disappeared. “It was quite sad, actually,” Dupoué says. “It’s something that is really happening at a rapid pace.”