Climate change could cut lifespan of cold-blooded animals
Climate change could reduce the lifespan of hundreds of amphibian and reptile species, new research suggests. Scientists say their findings suggest global warming could be impacting the internal workings of the animals and forcing them to work harder in order to survive. Warmer ambient temperatures forces the metabolism of these animals to speed up and this accelerates senescence, or ageing, and shortens their life expectancy. Scroll down for video The researchers from Queen's University, Belfast and Tel Aviv University analysed data from more than 4,100 land vertebrate species globally. A total of 2,214 endotherms (warm-blooded) and 1,886 ectotherms (cold-blooded) were compared to see what affected their ageing. Academics investigated a long-held theory that states the faster the metabolic rate of an animal, the shorter its lifespan. But when this was put to the test, it was environmental temperature, not metabolic rate, that had a more significant impact on lifespan. In the study, the authors put forward another layer to the theory that states the hotter the environment is, the faster an animal's metabolism. This then accelerates ageing and shortens an animal's lifespan. 'Our findings highlight the potential for rapid warming, resulting from the current increase in global temperatures, to drive accelerated rates of senescence in ectotherms,' the researchers write in the journal . The study paints a complex picture of how climate change is affecting the world's amphibians and reptiles. Dr Daniel Pincheira-Donoso, co-author of the study from Queen's University, added : 'Our findings can have critical implications for our understanding of factors that contribute to extinctions, especially in modern times when we are facing a worldwide decline of biodiversity, with cold-blooded animals being particularly endangered. 'Now we know that the life-expectancy of cold-blooded vertebrates is linked to environmental temperatures, we could expect to see their lifespans further reduced as temperatures continue to rise through global warming.' Dr Pincheira-Donoso, formally of the University of Lincoln, is a world leader in studying reptiles, particularly lizards. He specialises in using theoretical models to understand the bigger picture of the world's cold-blooded animals. Fieldwork in the Andes has turned him into a global authority on South American lizards but his methods translate to studying past and future extinction events. He has tackled how the five mass extinction events in Earth's history shaped the diversity of life on Earth. Applying both these areas of speciality to the fact nearly one in five of the world's estimated 10,000 species of reptiles are threatened with extinction allowed the researchers to understand how soaring temperatures may affect ectotherms. Gavin Stark, lead author and PhD student at Tel Aviv University and first author, said: 'The link between lifespan in cold-blooded animals (amphibians and reptiles) and ambient temperatures could mean that they are especially vulnerable to the unprecedented global warming that the planet is currently experiencing. 'Indeed, if increasing ambient temperatures reduces longevity, it may make these species more prone to go extinct as the climate warms.' The scientists say understanding about the link between biodiversity and climate change needs to be developed.