In the past month, the front lawn has gone through a major transformation. Once green trees have become bathed in red, yellow and orange. Once healthy leaves have gone brittle and gathered on the ground. You might look at these changes and wonder: “Why does this happen?”

Courtney Kiley’s Ecology class has just the answer.

Due to a drop in temperature, the chlorophyll production in leaves goes down and as a result, some leaves start producing different pigments. For instance, some leaves produce carotenoids which give off a yellowish hue and others produce anthocyanins which give off a reddish hue. Some leaves stop producing pigment altogether, wilting and dropping off the tree.

“The process is so fascinating and beautiful,” Kiley said. “I love the sound of walking through the woods, that crunchy leaf sound. It’s also just so stunning on my eyeballs.”

Now, when you look out at the warm colors and crunchy leaves on the front lawn, just know that science is the reason for it all.