UC Davis graduate student Jeffrey Groh has discovered how walnut trees are able to produce flowers of different sexes at different times in the same season. The genetic mechanism is similar to sex determination in many animals. Pictured, Groh with a California black walnut tree on the UC Davis campus. Credit: Sasha Bakhter, College of Biological Sciences ============================================================================ Biologists at UC Davis have uncovered a fascinating genetic mechanism in walnut trees, allowing them to alternate between male and female flowers each season—a trait stable for 40 million years. This discovery not only sheds light on plant reproduction but also parallels...