The Connection Between Brain Size and Intelligence

Size Isn’t Everything: Big brains don’t always mean big intelligence — it’s how efficiently neurons connect that counts.
The Encephalization Edge: Scientists compare brain size to body size; species with higher ratios, like humans and dolphins, show greater intelligence.
Density Over Volume: Birds pack more neurons per gram than mammals, explaining why crows and parrots rival primates in problem-solving.
Smart Small Minds: Some small-brained creatures, like bees, display remarkable navigation and learning through optimized neural circuits.
Cortex Counts: The cerebral cortex, not total mass, is the key — its folds increase surface area for complex thought.
Energy and Evolution: Large brains demand huge energy supplies, so intelligence evolved only when survival made it worth the cost.
Social Sparks: Species living in groups often evolve bigger brains to manage relationships, alliances, and communication.
Developmental Investment: Longer childhoods allow more brain growth and learning, linking time to maturity with intelligence potential.
Plasticity Over Power: Adaptability — the ability to rewire and learn — often matters more than brain size itself.
The Human Leap: Our brains grew not just larger but more connected, blending memory, imagination, and language into conscious intelligence.