NIHPriscilla Long is tracing the line from LUCA, the Last Universal Common Ancestor, to Lucas, her five-year-old grandnephew. In β€œHow Chemistry Became Biology” for American Scholar (subscription required), Priscilla @PriscillaLong explores the genetic connectedness of all life on the planet. It’s a sneak peek into the theme of her new book, which will be available later this year. photo: NIH