Climate and fossil records show that large swings in the Earth’s average temperature over eons radically changed the distribution and composition of life on the planet, wiping out entire groups of plants and animals in some areas, including large land mammals, while allowing others to thrive in unexpected places. The fossil record is replete with evidence of things like beech trees in Antarctica.
Few, if any, species have survived a climate shift as abrupt as the one caused by humans’ greenhouse gas emissions and global disruptions of the forest, field, and aquatic ecosystems. In both hemispheres, fish are swarming poleward, and trees are climbing higher up mountainsides to escape the rising heat. Some species will simply outnumber themselves as equatorial waters and many mountaintops become too warm for them.
Some of that migration appears to be moving downward now. Scientists demonstrated that global warming and habitat degradation appear to be driving many arboreal primates down from the trees and onto the ground, where their survival is uncertain, in new research published Oct. 11 in the Proceedings of the National Academy of Sciences.
According to Timothy Eppley, lead author of the study and a wildlife researcher at the San Diego Zoo, conservation scientists will need to develop and quickly implement effective strategies to protect them. Otherwise, “they’ll just end up in these fragments [of habitat] and slowly die off because they have a limited gene pool and can’t disperse,” he said.
While shifting climates shaped primate evolution over geologic time scales, including causing some that lived in trees to move to the ground, Eppley believes none of the 47 species studied by his international team in the Americas and Madagascar will transition to a fully terrestrial lifestyle. He explained that there simply isn’t enough time.
“You know, the rate at which climate change and anthropogenic factors are degrading habitats is just so fast,” he explained.
Species that are less adaptable, such as those that rely on tree fruits or live in very small groups, are particularly vulnerable, and efforts to protect habitat for them are falling behind the effects of global warming, he added.
“There are multiple national parks on fire right now in Madagascar, for example,” he said. “I believe 40 percent of the Baie de Baly National Park in Northwest Madagascar has burned.” Isalo National Park, one of Madagascar’s most popular tourist destinations, is currently on fire, and this is similar to what you see in Brazil, especially at this time of year.”
Long-term conservation plans, such as reforestation and the establishment of migration corridors, are important, but “I would also say that we need to put in efforts simply to protect the habitats that we have,” he said. Because some primates only reproduce every few years, habitat changes can be “devastating.”
“We don’t have a lot of time when they’re dealing with these issues,” he says. “If something disrupts that natural reproductive pattern, you could be waiting 10 years between births, which is a really dire situation.”
