Enlarge / Despite the gaudy clothing, this guy is remarkably crafty. (credit: Arthur Morris)

One of the ways we try to understand the origins of human intelligence is by looking at its equivalents elsewhere in the animal world. But that turns out to be more complicated than it might seem. Humans have a large package of behavioral traits that we lump together as intelligence, while many other creatures only have a limited subset of those traits. Some aspects of intelligence appear in species widely scattered across the evolutionary tree, ranging from cuttlefish to giraffes.

Even in animals with widely acknowledged intellectual capacities like birds, it can be difficult to understand whether evolution has directly shaped their intelligence or their smarts emerged as a side effect of something else that evolution selected for.

A study released today complicates the picture a little further. It does persuasively show that the ability to learn complex new songs is associated with problem-solving in a large range of bird species. But it also shows that other things we associate with intelligence, like associative learning, seem completely unrelated.