At four months of age, Common Ravens’ cognitive performance may be similar to that of adult great apes on experimental tasks that test their understanding of the physical world and how they interact with other ravens, according to a new study published in Scientific Reports.
Simone Pika from the University of Osnabrück and colleagues tested the cognitive abilities of eight hand-drawn ravens at the age of four, eight, 12 and 16 months using a series of tests. The skills the authors examined included spatial memory, object persistence – the understanding that an object still exists when it is out of sight – the understanding of relative numbers and additions, and the ability to communicate with a human experimenter and to learn from him.
The authors found that ravens ‘cognitive performance was similar at four to 16 months of age, suggesting that the rate at which ravens’ cognitive skills develop is relatively rapid and nearly complete by four months of age . At this age, ravens become more and more independent of their parents and begin to discover their ecological and social environments. Although task performance varied among individuals, ravens generally did best when they tested adding and understanding relative numbers, and worst when they tested spatial memory.
Comparing the cognitive performance of the ravens with that of 106 chimpanzees and 32 orangutans who had performed similar tasks in a previous study, the authors found that, with the exception of spatial memory, the cognitive performance of the ravens was similar to that of orangutans and Was very similar to chimpanzees.
The results suggest that ravens, similar to great apes, may have developed general, highly developed cognitive skills. The authors suggest that ravens developed these skills in response to living in an ever-changing environment where survival and reproduction depend on cooperation and alliances between ravens. The authors caution, however, that the performance of the ravens studied may not be representative of the species in general.
Watch videos of the ravens
In this assignment, a researcher tested whether ravens understand that objects can change their location. Three cups were placed in a row in front of the ravens, and the experimenter then switched the position of the bait bowl with one of the empty cups. Photo credit: Miriam J. Sima.
In this assignment, a researcher tested whether ravens could use visual cues to find food. The experimenter hid a reward under one of two cups (the left cup), but gives a clue of the location by holding an iconic photo marker showing the reward and changing her gaze. Photo credit: Miriam J. Sima.
In this assignment, a researcher tested whether ravens understand that objects can change their location. A treat was placed under one of three cups and then the tray was rotated 180 degrees clockwise. Photo credit: Miriam J. Sima.
Thank you to Nature.com for providing this news.
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