not so bird-brained
Scientists have long thought that only humans and apes were capable of planning ahead, but a study published Thursday in the journal Science suggests ravens can too. In fact, under some circumstances the birds displayed greater skill than 4-year-old children or chimpanzees at anticipating their future needs based on previous experiences.
Researchers tested ravens' planning abilities on a farm in Sweden. A zoologist taught five ravens he'd raised from hatchlings how to use a tool to open up a box that held a treat. He then presented the ravens with a test:
The next day, without the box present, the birds were offered a choice between the stone tool and "distracter" objects — toys too light or bulky to use as tools. The box would then be brought back 15 minutes after the selection. Despite the delay, the ravens chose the correct tool nearly 80 percent of the time, and successfully used the tools they selected 86 percent of the time.
The birds performed almost as well when they had to give an experimenter a bottle cap in exchange for a piece of food. The birds almost always selected the bottle cap over distracters, even though they would have to wait 15 minutes to barter with it. The preference for soon-to-be-useful items persisted when the ravens had to pass up a smaller treat in favor of either the tool or the bartering token — and even when they could use each item only after a 17-hour delay. [Scientific American]
The research raises the question of how bird-brained these birds really are, and also challenges scientists' conceptions of the evolution of intelligence. "It shows yet again how smart corvid songbirds can be even if they have a very different organization of their brains compared to primates and us humans," Andreas Nieder, a neuroscientist who was not involved in the study, told Gizmodo. "This is a fascinating case of so-called convergent evolution: similar intelligent behavior, but based on very different brain structures."