Two research teams have each used the biggest collection yet of flowering-plant genes to map out the floral family tree.
"We got the same answer," says Michael J. Moore of Oberlin College in Ohio. Both family trees show the same basic arrangement of the eight lineages that still bloom today. Five of the eight appear as short branches at the top, a sign that the five more-recent lineages split from each other rapidly. The new analyses calculate that when these lineages split at least 125 million years ago, the divisions took place in less than 5 million years.
Fast divergences are hard to reconstruct, so botanists have struggled to sort out the relationships among the more-recent lineages. Both of the new trees show the same position for the eudicots, the biggest flowering lineage, which includes many common plants, from buttercups to mustards. It turns out to be the closest branch to the second-largest lineage, the monocots, which include grasses, lilies, and related pl