Selection Is Keeping the Books

Every organism runs on a closed budget: energy comes in at some finite rate, and every single thing it does — staying alive, moving, growing, reproducing — is an expense drawn against it. What is left over after the bills is the only thing that can be turned into offspring. And offspring are what evolutionary fitness counts. Not strength. Not speed. Not health. Offspring. Watch a unit about chemistry end somewhere ruthless.

AP BIOLOGY · 8 STEPS · 6 QUICK CHECKS · FITNESS = SURVIVING OFFSPRING · NET, NOT GROSS · THE BUDGET IS CLOSED · v1