Have you ever solved a tricky puzzle? As kids, Joanna Kelley and her siblings had fun solving the math and science challenges their parents invented at the dinner table. Later, Kelly's love of science puzzles inspired her to investigate the building blocks of life. Kelley became a geneticist, a scientist who studies DNA. DNA is the set of instructions inside every living thing—a code that shapes appearance and behavior. Kelley set out to better understand how the code works. She focuses on a wide range of animals, from great apes to tiny insects. What she learns about their DNA can tell scientists a lot about human DNA too. Follow Kelley's path from curious kid to groundbreaking scientist.