The Mating Mind — Geoffrey Miller (2001)
Author: geoffrey-miller
Publisher: Anchor Books (Random House), April 2001 (paperback); original hardcover Doubleday, 2000
Raw file: raw/papers/The Mating Mind How Sexual Choice shaped the Evolution of Human Nature - Anchor Books-Random House (Miller G., (2001)) (z-lib.org).md
Overview
Miller opens with a puzzle: on one side of Central Park is the Museum of Natural History (natural selection, survival, survival tools); on the other side is the Metropolitan Museum of Art (art, music, moral virtue, self-consciousness). How did proto-humans cross from one side to the other? Standard survival-selection accounts explain tools and trade, but struggle with art, elaborate language, humour, and moral sentiment.
Miller’s answer is sexual-selection — specifically, Darwin’s mate choice mechanism. Sexual selection can generate extravagant, costly, seemingly useless traits because potential mates use those traits as indicators of genetic fitness. The peacock’s tail is the canonical example; Miller argues the human mind is another.
The Two Mechanisms of Sexual Selection
Darwin identified two mechanisms: intrasexual competition (males fighting each other) and intersexual choice (choosy females selecting among males). Miller focuses on the second.
Two theoretical frameworks explain how costly ornaments evolve:
- Runaway selection (Fisher process) — a preference for a trait and the trait itself co-evolve in a self-reinforcing loop. Even arbitrary traits can “run away” to extremes if females with the preference reproduce more successfully.
- Fitness indicators / handicap principle (Zahavi) — only traits that are genuinely costly to produce can be reliable signals of genetic quality (cannot be faked cheaply). The fitness-indicators concept: a peacock bearing a large tail despite the survival cost thereby advertises that it has the genetic resources to survive despite the handicap.
The “Runaway Brain” Thesis
Chapter 3 (The Runaway Brain) proposes that runaway-selection can explain rapid expansion of the human brain beyond what survival alone required. Once females began preferring mates with slightly larger, more versatile minds (for better courtship behaviour, problem-solving display, or verbal creativity), the preference and the trait co-evolved rapidly. The extraordinary pace of hominid brain expansion (roughly tripling in 2 million years) fits the predicted signature of a runaway process better than any gradual survival-advantage account.
Intelligence as a Fitness Indicator
Chapter 5 (Ornamental Genius) argues that general intelligence — the g factor — functions as a fitness indicator. High-g individuals are better at creative courtship across multiple domains (verbal, musical, humorous, moral). Since g correlates with overall developmental stability and resistance to genetic mutation load, it is a genuine signal of genetic quality.
This reframes IQ and general intelligence: not just a tool for solving survival problems, but an evolved display mechanism shaped by choosy mates across hundreds of thousands of years.
Language, Art, Humour, and Morality as Courtship Displays
| Capacity | Miller’s Argument |
|---|---|
| Language (Ch. 10 — Cyrano & Scheherazade) | Verbal creativity, vocabulary richness, narrative skill signal intelligence and creativity; storytelling ability evolved partly as courtship |
| Art (Ch. 5, 8 — Ornamental Genius, Arts of Seduction) | Art is conspicuous waste of time and mental resources — exactly what a costly fitness indicator requires; art-making signals genes for creativity, fine motor control, and sustained attention |
| Humour (Ch. 11 — The Wit to Woo) | Humour production (not appreciation) is cognitively demanding and hard to fake; consistent wit signals mental agility and social intelligence |
| Moral virtue (Ch. 9 — Virtues of Good Breeding) | Altruism, fairness, and courage advertise fitness by imposing real costs; “good character” may be an evolved display of genetic quality, not just a cultural overlay |
Courtship in the Pleistocene (Chapter 6)
Miller surveys evidence for Pleistocene hominid behaviour: multi-hour grooming, music (vocal and percussive), body decoration, and storytelling around campfires. He argues these activities make more sense as courtship displays than as pure survival tools, and that the Pleistocene environment provided the evolutionary stage for sexual selection to operate at full strength.
Bodies of Evidence (Chapter 7)
The book examines physical fitness indicators (symmetry, secondary sexual characteristics, waist-hip ratio) that evolved through sexual selection. The key insight is that the same evolutionary logic that shaped physical ornaments also shaped mental ornaments — both are honest signals because they are costly to produce and hard to fake.
Key Claims
| Claim | Where |
|---|---|
| Human brain tripled in size too fast for survival selection alone | Ch. 3 (The Runaway Brain) |
| General intelligence is a fitness indicator signalling genetic quality | Ch. 5 (Ornamental Genius) |
| Art, language, humour, and morality are partly evolved courtship displays | Ch. 5, 8, 9, 10, 11 |
| Survival-selection accounts leave art, ethics, and elaborate language unexplained | Ch. 1 (Central Park) |
| Sexual selection requires choosiness (the other sex must be highly selective) | Ch. 2 (Darwin’s Prodigy) |
Relationship to Existing Concepts
This book introduces a new domain to the wiki — evolutionary-psychology — and enriches understanding of several themes:
- Connects to communication-channels (language as display, not just utility)
- Provides evolutionary grounding for social skills (art/humour as mate attraction)
- Suggests that creativity and intelligence have fitness-indicator origins
Entities Mentioned
- geoffrey-miller — author; evolutionary psychologist; LSE / UCLA
- Charles Darwin — originator of sexual selection theory
- Ronald Fisher — runaway selection / genetic theory of mate choice
- Amotz Zahavi — handicap principle / honest signalling