How Mice (and Their Characters) Determine Where Trees Grow

About the episode

When you walk through a forest, you probably rarely think about how that tree ended up there. Maybe, when you think about it, it looks like a coincidence. Or something that is controlled by the space available and how the tree itself uses it.

But University of Maine biologist Ivy Yen knows better, according to The New York Times. In a gigantic experimental forest, she researches the link between the propagation of tree seeds and the behavior of the animals that carry them with them.

In this forest, the research group to which she belongs has already provided 2,000 mice and voles with a traceable chip in seven years. These animals were regularly offered trays with the seeds of local trees. A wildlife camera always recorded which animal ran away with which seed. A non-toxic powder on the ground would then indicate where they had taken the seed and if it was kept somewhere or had been eaten.

Researchers are now analyzing all this data, from all these seeds, their fate and the behavior of their carriers. They have already seen that the character of the animals helps determine which seeds they take with them and also that the presence of predators influences the way the seeds are handled.

They also saw that there were more brave animals in areas of forest where felling took place and that in a wild forest there was more variation in personalities. Researchers hope to find out a lot more about how this all contributes to where the tree grows. Because if we want to protect our ecosystems and chart their future, we must first know how they are formed.

Read more: Meet the mice that make the forest.