Extra nuclei produced by training survive disuse, making it easier to rebuild lost strength. (p. 15)

When tiny hairpin-shaped molecules act up, they don’t rebel loner-style like James Dean. Instead they take on the persona of Darth Vader, crushing proteins under their command and turning acquaintances to the dark side as well. In this case, though, the fight is for control not of the universe, but of the body. And a dark-side victory could end in cancer. No one would have predicted a decade ago that these microRNAs, as the hairpins are called, were involved in cancer, because no one even knew that they existed in people. Mere snippets of RNA — DNA’s underappreciated cousin — thes... (p. 18)

Genome reveals that the first animals had a complex tool kit. (p. 8)