We often define intelligence in human terms, calling someone smart if they can solve complex math problems or write a great novel. But intelligence in the animal world is measured in more species-specific ways. Birds’ complex brains allow them to solve problems and adapt to their surroundings, like finding food and avoiding predators, while their social intelligence helps them navigate advanced and changing social structures.
New research shows that the underlying complex brain structures required for intelligence evolved separately for birds and humans. This convergent evolution resulted in similar neuronal circuitry for the two groups, despite very different brain structures. These studies (find them here, here and here) found that during embryonic development, brain circuitry develops differently for birds and humans. Since embryonic development reflects evolutionary history, the researchers conclude that animal intelligence evolved independently at least twice in vertebrate animals.