Convergent Evolution of Intelligence

Convergent evolution is the phenomenon by which natural selection independently arrives at the same functional solution in organisms with no recent common ancestor. The eye has evolved independently at least forty times across the tree of life—in vertebrates, mollusks, arthropods, cnidarians—through different developmental pathways using different genetic machinery, arriving at functionally similar structures because the physics of light constrains the space of viable solutions. Echolocation evolved independently in bats and dolphins. Flight evolved independently in insects, birds, pterosaurs, and bats. Complex nervous systems evolved independently in vertebrates and cephalopods. Each case demonstrates that the space of viable biological solutions is far smaller than the space of possible forms, and that evolution reliably finds the viable solutions because they are attractors in a landscape shaped by physics and mathematics. Davies extends this principle to intelligence itself: complex environments present problems that cannot be solved by fixed responses, and the organism capable of flexible, real-time information processing has an enormous selective advantage. Intelligence, in this framework, is not a contingent