The Most Controversial Idea In Biology

Genes are the fundamental unit of natural selection, not individuals or species. They are 'selfish' replicators that use organisms as survival machines to propagate themselves.

• 🧬 Genes are the core unit of natural selection because they are stable, self-replicating entities that influence traits.
• 🐒 Altruism, like worker bees stinging predators or squirrels giving alarm calls, can be explained by kin selection: genes promoting survival of relatives help preserve copies of themselves.
• 🔄 Sexual reproduction, despite halving gene copies, may persist because genes regulating it benefit from the variation it creates.
• 🎲 Genetic drift, random changes in gene frequency, can override natural selection, especially in small populations or for neutral traits.
• 🧠 The 'selfish gene' concept is a metaphor; genes lack consciousness or intent, merely reacting via chemistry.

A silhouetted human figure stands in the center, surrounded by images of a monkey, a dinosaur, an ostrich, and a caveman, all on a grid with glowing blue lines.