By her own estimate, Susan Milius has considered writing about the downfall of biological kingdoms for some 10 years. That long contemplation made it somewhat difficult to pare all the material down to a six-page feature article. But I think readers will agree that she has succeeded admirably, outlining the shifts in scientific understanding that have uprooted previous notions of the tree of life.
Milius describes how genetic tools, which initially led scientists to misconstrue connections, are now beginning to clarify relationships in the panoply of eukaryotic life-forms. It’s a fascinating tale of how peering deep into the history of evolution has revealed unexpected richness and complexity, even in the supposedly simple single-celled organisms.