New research shows that apes have a better memory than some humans.
A research team studied a group of apes as the animals were shown photos of old friends — some of which they hadn’t seen in over 25 years — and the animals’ reactions to the photos.
The study was published in the Proceedings of the National Academy of Sciences peer-reviewed journal.
Lead author Dr. Laura Lewis from the University of California, Berkeley told SWNS that the animals are actually very similar to humans.
“We tend to think about great apes as quite different from ourselves, but we have really seen these animals as possessing cognitive mechanisms that are very similar to our own, including memory,” she said.
The team of researchers worked with chimpanzees and bonobos at three zoos — the Edinburgh Zoo in Scotland, the Planckendael Zoo in Belgium and the Kumamoto Sanctuary in Japan, as SWNS reported.
Then the researchers, including co-author Christopher Krupenye of Johns Hopkins University, collected images of apes no longer at the zoo — individuals the other apes hadn’t seen in at least nine months or even for as long as 26 years.
The researchers also wanted to know of any relationships that current ape residents had with the ones who left — wondering if they would have any positive or negative feelings associated with those relationships.
Once preparations for the study were underway, researchers invited the chimpanzees and bonobos to participate by offering them juice.
Once the apes were interested and partaking, they were shown two side-by-side photographs — one of an ape they had met before, and one photo of a stranger.
Researchers then used a non-invasive eye-tracking device to measure where the apes looked and for how long — to see if they were recognizing the ape they had met previously.
What the team found was that the animals tended to stare at the familiar image for “significantly” longer than the animal they had never met.
The apes also looked longer at the animals they’d had positive interactions with in the past, SWNS reported of the research.
Researchers said the most interesting finding from the experiment was when a bonobo named Louise was shown an image of her sister and nephew — whom she had not spotted in more than 26 years.
She gave a “strikingly robust” look toward both of them over eight separate comparisons, said SNWS.
Lewis told SWNS that researchers can conclude that the memory strength in these animals is similar to that of humans.
“This pattern of social relationships shaping long-term memory in chimpanzees and bonobos is similar to what we see in humans, that our own social relationships also seem to shape our long-term memory of individuals,” she said.
She continued, “The idea that they do remember others, and therefore they may miss these individuals, is really a powerful cognitive mechanism and something that’s been thought of as uniquely human.”
Lewis said that although the study does not determine that apes have this type of emotion attached to missing others, it does “raise questions about the possibility that they may have the ability to do so.”
Krupenye told Fox News Digital that he hopes to better understand the memory that apes have.
“In the future, we hope to better understand the nature of ape memory — for example, whether seeing the faces of familiar individuals leads them to replay past social interactions in their minds,” he said.