To my wide-eyed warrioresses,

Cradling your daughter in your arms for the first time changes you—and your future—forever. Since my two daughters emerged into this world, all of my tomorrows have become more dear.

A climate-changed world is anything but a proud legacy, my dear daughters. But you have given me gifts more powerful than despair: wonder and curiosity, as well as the passion of my eldest and the resolve of my youngest. A father relearns about the world through the eyes of his daughters, which is to say that legacy can flow both backward and forward.

Whether it’s a vortex of 400,000 Brazilian free-tailed bats rising in the twilight above Carlsbad Caverns, a Marmota Olympus standing vigil outside its burrow on Hurricane Ridge or a moonrise above the canyons of Mukuntuweap National Monument, our planet is a place of profound beauty and complexity. Its emergence out the cosmos has been a fantastic journey, and this world will not go quietly into the night.

You are both authors of its coming chapters. Humanity has lurched along, inflicting both harm and help, not always in equal measure. Perhaps it’s time for “womanity” to take the lead. Teach me the things I must do, both big and small, then reteach me as new knowledge emerges.

But first, let’s hike somewhere together. The journey to a forever planet starts with a single step.