Why are some birds more intelligent than others?

If you’ve ever seen a grackle steal your dog pellets or a starling peck open a garbage bag, you get a sense of that some birds have learned to take advantage of new feeding opportunities — a clear sign of their intelligence. Scientists have long wondered why certain species of birds are more innovative than others, and whether these capacities stem from larger brains (which intuitively seems likely) or from a greater number of neurons in specific areas of the brain. It turns out that it’s a bit of both.