*Behave: The Biology of Humans at Our Best and Worst* is a book written by Robert Sapolsky, published on May 2, 2017. In this comprehensive and engaging work, Sapolsky, a renowned neurobiologist and primatologist, explores the biological underpinnings of human behavior, offering a deep dive into the complex interactions between genetics, environment, evolution, and neurobiology that shape how humans act.

The book is divided into sections that address the biological mechanisms at play in the context of behavior, including how genes, hormones, brain activity, and evolutionary forces influence our actions. Sapolsky examines both the “best” and “worst” aspects of human behavior, from acts of compassion and cooperation to violence and aggression.

Key themes in the book include:

1. **Neuroscience and Behavior**: Sapolsky delves into how the brain works in terms of decision-making, impulse control, and moral reasoning, offering a detailed explanation of how these processes govern human actions.

2. **Evolutionary Influences**: The book discusses how our evolutionary history has shaped our behavior, with both adaptive and maladaptive traits influencing modern human actions.

3. **Socio-Environmental Factors**: Sapolsky takes into account how environmental factors, upbringing, culture, and society affect human behavior. He emphasizes that our actions are not solely determined by biology but are also shaped by external influences.

4. **Ethics and Free Will**: A central theme of the book is the question of free will. Sapolsky challenges the traditional notion of moral responsibility by highlighting the many factors—biological, environmental, and historical—that influence our choices.

The writing is both scholarly and accessible, making complex scientific concepts understandable to a general audience. Sapolsky uses a mix of humor, storytelling, and scientific rigor to explain his points, which has made the book popular with both general readers and academics.

*Behave* offers a rich and multifaceted perspective on human nature, encouraging readers to think critically about how we understand ourselves and others in both our best and worst moments. It is widely regarded as a definitive work on the biology of human behavior.