http://www.sciencemag.org/news/2018/07/could-tiny-spider-be-helping-arctic-stay-cool

Wolf spiders change their diets when it warms, leading to ecosystem shifts that could buffer against further warming.

The 4-centimeter-long wolf spider may be having an outsize effect on the Arctic climate. When temperatures rise, the aggressive, ambushing arachnids switch up their diets, eating each other instead of an insect that keeps a greenhouse gas–belching fungus in check, researchers report. As a result, the spiders may be indirectly reducing greenhouse gases over the Arctic and keeping the region cooler than it would be otherwise.