(Reuters) – The U.S. National Weather Service Miami-South Florida warned the public on Sunday that immobilised iguanas could fall out of trees due to unusual cold temperatures across the region. “Iguanas are cold-blooded. They slow down or become immobile when temps drop into the 40s (4-9 Celsius). They may fall from trees, but they are not dead,” the service said on Twitter. Temperatures in South Florida reached a low of 25 degrees Fahrenheit on Sunday morning, according to the National Weather Service, and high temperatures on Sunday were expected to remain in the upper 50s to low 60s. The n…