The Selfish Gene, published in 1976, took an idea from the 1960s — that natural selection acts on genes rather than on individuals or groups — and made it intelligible to a non-specialist audience. The book is fifty years old this year. The argument has held up. What has changed is how much we now understand about everything else: how genes interact with development, how brains generate behavior, how explanation itself works as a kind of knowledge. The follow-ups below sit alongside Dawkins rather than after him.
Read in this order, they widen the frame. Deutsch on what good explanations are. Davies on the universe that made evolution possible. Sapolsky on the full causal chain behind any single act.
The Beginning of Infinity — David Deutsch
Deutsch is a physicist at Oxford and one of the founders of quantum computing. The Beginning of Infinity is his book on explanation — what a good explanation is, why some explanations are better than others, and why the capacity to construct good explanations is what makes humans different from every other species and every other kind of optimization process, including natural selection. The chapter on the reach of explanations is the closest thing in print to a philosophy-of-science companion to Dawkins.
"Everything that is not forbidden by laws of nature is achievable, given the right knowledge."
It is a denser book than The Selfish Gene, and an argumentative one — Deutsch is in conversation with Popper, with Lakatos, with Hayek. Read slowly. The reward is a vocabulary for distinguishing real understanding from clever-sounding analogy, which is exactly what The Selfish Gene needs as a follow-up.
The Goldilocks Enigma — Paul Davies
Davies is a cosmologist whose career has been spent on the question Dawkins largely ignores: why is the universe the kind of place in which evolution is even possible? The book surveys fine-tuning — the observation that the fundamental physical constants seem improbably calibrated for the existence of complexity — and the candidate explanations: the multiverse, the anthropic principle, a designer, a deep mathematical necessity we have not yet identified.
Davies is a working scientist, not a polemicist. The book is careful, well-written, and surprisingly willing to entertain explanations that contemporary biology would prefer to dismiss. It is the book to read when The Selfish Gene's confidence in mechanism starts to feel slightly too narrow.
Behave: The Biology of Humans at Our Best and Worst — Robert Sapolsky
Sapolsky is a neuroscientist and primatologist at Stanford, and Behave is his synthesis of decades of work on what causes a single human behavior. The structure is brilliant. He starts with the act itself — a person throws a punch, or makes a gesture, or speaks a sentence — and then walks backward through the causal chain: the second before, the minutes before, the hours, the years, the millennia. By the end he has gone from neurons to evolution, in one continuous argument.
"It is virtually impossible to understand how biology works, outside the context of environment."
Where Dawkins gives you the gene as the unit of selection, Sapolsky gives you the gene as one strand in a system that also includes hormones, neural circuits, culture, and history. The combination is what contemporary biology actually looks like. Behave is long — seven hundred pages — but each chapter is self-contained.
If you want to go deeper
Hamilton was the British evolutionary biologist whose 1964 papers on inclusive fitness and kin selection are the actual source of the gene's-eye view that Dawkins later popularized. Narrow Roads of Gene Land collects Hamilton's papers across three volumes, each prefaced by autobiographical essays that are, on their own, some of the finest writing about scientific work in English. Hamilton was an unusual figure — eccentric, beloved by colleagues, fieldwork-driven, and prone to wild speculation — and the essays catch all of it.
Read the first volume. The technical papers are genuinely technical, but the autobiographical material is accessible to any patient reader, and you come away with a sense of how an idea actually gets made — which is messier and more human than The Selfish Gene's clean exposition lets on.