One of the oldest philosophical puzzles is the question of what sets human beings apart from other animals. A common answer is that just human beings can understand that others also possess minds like their own.

However, a latest study has suggested that ravens, which are the birds marked out by several cultures as a symbol of intelligence and wisdom, share at least a bit of the human ability of thinking abstractly regarding other minds, adapting their actions by attributing their own perceptions to others.

The study titled ‘Ravens Attribute Visual Access to Unseen Competitors’ appeared on February 2 in Nature Communications. It discovered that ravens guarded food caches against discovery responding to the sounds of other ravens if a close by peephole was open, even if they haven’t witness other bird. Despite the auditory hints, they did not show similar concern when the peephole was shut.

Cameron Buckner, assistant professor of philosophy at the University of Houston said that the finding has shed fresh light in science's understanding of Theory of Mind, the capability to attribute mental states, like vision to others.

Most Theory of Mind study consisting of animals has been conducted on chimpanzees and other species closely linked to human beings. However, while those studies have indicated that animals can understand what others see, which gives them a benefit in competing for food, for instance, they depend on the test subjects' ability of seeing another's head or eyes, providing so-called ‘gaze cues’.

Skeptics have argued that the animals that participated in these experiments might be responding just to these surface cues, without any actual understanding of what others witness.

So, while explaining the past state of the research, the authors wrote, “It still remains an open question whether any nonhuman animal can attribute the concept 'seeing' without relying on behavioral cues”.