Humans 101

Why Do Leaves Change Color?

A lesson from children about etiology, phenomenology, epistemology, and learning ethics from nature

Tyler Kleeberger
Human Parts
Published in
17 min readSep 28, 2020
Autumn leaves.
Photo: ooyoo/Getty Images

Asking questions about autumn

The sun’s path appears to be bending south, adding a dull hue to summer’s bright skies. The last efforts at growth showcase the skills of plants not yet ready to die. Humidity vacates the air, replaced by a crisp breeze. Even the sun seems compelled to offer new ventures of color — bending light among increased clouds, resulting in vibrant displays of reds, oranges, and the occasional purple on the horizon at the end of a now-shortened day.

It is the one time of year those of us living in temperate climates take pride in our weather.

There is nothing quite comparable to the season called Autumn.

Outside the pumpkin spice craze, there’s nothing I would get rid of about this season. I’ve lived in climates that escape winter’s cold and, if I’m honest, my soul felt empty without Fall. The taste of a fresh Northern Spy apple picked in late October, the smell of a recently harvested field, and the increased attention we give to celebrating life as we sense the closing of a year and the onset of winter.

I have yet to mention the most visible, striking, and physically awe-inspiring event of Autumn — something my area of residence boasts about. The animated alteration of the trees as their foliage abruptly changes from the assumed green of summer’s spell to a cascading cornucopia of deep, rich palettes.

Our culture loves this phenomenon. Folks take special vacations just to see it. There are travel guides revealing the routes to take to see the most and best changing foliage possible. Why are we so mesmerized by this process? Most other plants end their year by quickly fading into a beige piece of compost. But not trees. Both marvelous and mystifying, why don’t leaves suffer the same fate as most every other living plant as the year ends?

But the question is worth asking: Why do leaves change color?

The answer not only deepens our appreciation of the physical world but can provide existential insights into our strange…



Tyler Kleeberger
Human Parts

Pursuing what it means to be human so as to build the best world possible. Practical ethics through in-depth exploration. Becoming Human: