Ravens, crows and their relatives are incredibly smart.
Regarding raven memory, prior research found that a "raven can remember a single encounter with a human for at least a month", so "they can remember information for a very long time", Osvath said. Quoth the raven: Nevermore.
Cognitive scientists from Lund University, Sweden, spent hours watching the corvids to determine that they are able to think ahead to future scenarios.
Kabadayi and Osvath trained the ravens to use a rock as a simple tool to open a box containing a treat, if the birds dropped the rock through a small tube.
The researchers wanted to see if five ravens could plan while doing tasks that they don't normally do in the wild, specifically using tools and bartering.
The ravens had seen the tool and the distractions the day before, and learned then that the tool opens the box. Almost 90 perecnt were able to open it, having snagged the right tool.
Repeatedly, through 14 trials, the birds chose and used the correct tool 79 percent of the time-much higher than chance. The ravens planned for bartering more accurately than apes, the researchers report, and they were on par with them in the tool-using tasks, despite lacking predispositions for tool handling.
The ravens were as good with tools as apes, and in some ways better at bartering, outperforming orangutans, bonobos and chimpanzees, according to the study.More news: Watch never-ending handshake between Trump and Macron
As a result of the study it was deemed that ravens have the ability to plan ahead in life but not just when it comes to hiding and storing their food. But there has been debate about whether those findings showed the animals could indeed plan ahead; Other animals that aren't thought to be able to plan for the future, like squirrels, also cache food. A fifth bird was meant to be involved in the study but it was deemed too neophobic - or scared of new things - to take part. They last shared an ancestor about 320 million years ago.
Why would ravens develop the ability to plan?
Although the evidence is new, the ability of ravens to see ahead has always been suspected: In Greek mythology, they are associated with the god of prophecy, an old term for a group of ravens is "conspiracy" and in Game of Thrones a three-eyed raven appears in a prince's prophetic visions. Is that a raven?
Ravens are complex birds. But some of them decide to stick around and sneak bits of food from humans.
Next, the ravens were presented with the correct, apparatus-opening tool, distractor tools, and an immediate reward, but were only permitted to select one item.
Until now, some corvids - the family of birds that includes ravens - have shown the ability to plan beyond the present, for example by hiding food for later.
"He does all kinds of insane things", Sangris said, before sharing a tale of vengeance that only a creature with a good memory and the ability to plan ahead could pull off. "[It's evidence] that general intelligence has also developed in birds".