Biological sex is the sole basis for defining the words “male,” “female,” “father,” and “mother,” according to new guidance published Wednesday afternoon by the Department of Health and Human Services ...

Amid the legal theater in the U.S. over sex and gender identity—triggered by a Trump administration decree that “‘sex’ shall refer to an individual’s immutable biological classification as either male ...

In Focus delivers deeper coverage of the political, cultural, and ideological issues shaping America. Published daily by ...

Introduction: Carving nature at its joints, or Why birds are not dinosaurs and men are not apes -- Part I. The Interrelationships of Organisms: 1. What this book is about -- 2. Classification -- Part ...

List of illustrations -- Acknowledgments -- Introduction -- 1. Why classify? -- 2. The Aristotelian framework -- 3. The Darwinian pivot -- 4. Evolutionary taxonomy and the cladistic challenge -- 5.