As global temperatures continue to rise, with an expected overall increase of up to 2 degrees Celsius by 2100, plants and animals will both need to find ways to either survive in warmer climates, or migrate to cooler places.
The easiest way to do this is by moving up mountains. Changing elevation results in a more significant temperature change than moving north or south, by as much as 100 to 1,000 times.
It’s for that exact reason that both Asiatic black bears and Japanese martens have been moving up in elevation in Japan recently. They’re seeking cooler temperatures, and in turn, they’re also moving cherry trees up there with them.
The animals eat or store cherries as the head up, and subsequently defecate seeds or forget about the cherries, allowing new cherry trees to take root in cooler climates.
About one third of all plants rely on animals to move their seeds to new locations, allowing those plants to spread out and improve their chances for survival. But so far, we don’t understand the complexities of this process all that well. That’s because it’s an incredibly complex process built upon multiple, interacting ecosystems.
On the face of it, animals eat fruit and the seeds pass through their digestive tract unharmed, which sounds pretty simple. But that doesn’t actually tell us what animals eat what fruit, how well those seeds survive, where they can take root, and so forth.
Different plant species in different regions, and even one species from region to region, can have wildly varying levels of success with this method, depending on the types of animals which are native tot eh region, or which happen to be passing through.
More studies that focus on these movements will be necessary in order to build a better understanding of how such plants will mange to survive increasing temperatures in the future.