In the entirety of the animal kingdom, humanity has never held a monopoly on intelligence: considering that the concept of intelligence boils down to the ability to gather and usefully process information, this means that virtually all creatures possess at least some degree of intelligence. Humans tend to stand apart in this regard, due to the degree that our capacities have developed to, but even then many of these cognitive traits are shared with some of our non-human brethren: great apes such as chimpanzees are adept tool-users, prairie dogs have a sophisticated vocabulary, and octopuses have excellent problem solving skills.

And then there are ravens, considered one of the most intelligent known species. A new study on the cognitive abilities of the legendary black bird, conducted at Lund University in Sweden, ran a series of tests designed to determine the capacity to plan for the future, including bartering for desired resources.

The ravens were first tasked with retrieving food from an otherwise inaccessible box that required a specific tool to open it. They were then presented with just the box without the tool; then, presented with the tool without the box, along with an assortment of tools that would not open the box. 86 percent of the time, the ravens would pick the proper tool out of the assortment, implying that they knew it would come in handy for when the box next appeared.

Extending the experiment, the ravens were offered tokens that they could use to trade for the tool at a later time, with 76 percent of them succeeding at this task; and taken to yet another level, 73 percent of the ravens would put off taking an immediately available smaller reward in exchange for a larger one that could be acquired later on — a form of self-control that also requires forward-thinking to override the impulse of immediate gratification.

While ravens have been studied for their intelligence for many years, the study points out that the cognitive abilities demonstrated by these birds are on par with that of humans and the great apes, despite not having shared a common ancestor for hundreds of millions of years.

"[Birds and mammals] separated around 320 million years ago," explains the study’s lead researcher, Can Kabadayi. "Independent run of life for 320 million years, and you reach similar ends, cognitively, using different neural substrates. Is this a recurring pattern in evolution? Can intelligence also converge? These are fascinating questions that drive me."