In herds that number up to the tens of thousands, reindeer trek across the Arctic tundra while munching on shrubs and grasses. But as they graze, these animals are getting more than just nourishment -- according to a recent study reindeer could play a crucial role in controlling the effects of climate change.

"Grazing alters several ecosystem properties, such as plant species composition and soil nutrient availability, which in turn alter ecosystem responses to climate warming," says Sari Stark, a biologist at The Academy of Finland, in a press release. Stark and her colleagues published the results of the study online this week in Nature Climate Change.

Intense mammalian mowing, according to the Finnish researchers, encourages grass to grow back more rapidly -- which, in turn, takes more carbon out of the environment. Reindeer grazing habits, the study concludes, is a critical piece of understanding climate change in the tundra. And as the tundra heats up, releasing more and more carbon from once-frozen soil, any impacts to this habitat will continue to affect the way the world warms.