P.F. Ferrari

Just like humans and apes, geladas mimic each other's facial expressions to show an emotional connection.

By Tanya Lewis
LiveScience

The ability to mimic the facial expressions of others is thought to be linked to empathy. It's known that humans and orangutans "ape" each other in this way, but gelada monkeys appear to do it too, a new study shows.

The phenomenon, known as rapid facial mimicry, is an unconscious response that occurs when two animals are interacting. Researchers showed that geladas (Theropithecus gelada), a type of Old World monkey, show facial mimicry during play — particularly mother-infant pairs. The curious ability may have a common evolutionary root among primates, the researchers say.

"This mimicry relates to an internal emotional connection," said neuroscientist Pier Francesco Ferrari of the University of Parma in Italy, who co-authored the study published March 28 in the journal Scientific Reports. It shows that "basic forms of empathy are present in other species that are not apes," Ferrari told LiveScience.

The researchers observed adult and baby geladas at a zoo in Germany during playful interactions. They recorded the play sessions on camera, noting whether the animals imitated each other's facial expressions. Facial expressions included the "play face," (an open mouth with only the lower teeth exposed), the "full play face" (lips pulled back to expose the upper and lower teeth and gums) and "lip-smacking" (lips smacked together, sometimes with the tongue extended).  The play faces are considered the equivalent of laughter in humans, whereas lip-smacking can have different meanings depending on the context. [Image Gallery: Cute Gelada Monkeys]

The geladas mimicked each other's play faces and the full play faces, but not the lip-smacking. Furthermore, mother-infant pairs engaged in the behavior most, and were also fastest at it. The findings show that the mimicking behavior seen in humans and apes has a counterpart in monkeys. In addition, the similarities between mother-baby interactions in these species suggest a common evolutionary origin.

Rapid facial mimicry is thought to arise from brain areas linking perception and actions. Scientists studying monkeys have found evidence of brain cells known as mirror neurons, which are active both when an animal performs an action and when it watches another animal doing it. In humans, this mirroring may be implicated in empathy, the researchers say.

Neuroscientist Marco Iacoboni of the medical school at UCLA said he found the study's results compelling. "We thought for many years that empathy is a human accomplishment, something we came up with that distinguishes us from other species," Iacoboni told LiveScience in an email. "Yet, the more we dig into the animal kingdom, the more we see evidence for empathy, or at least its evolutionary precursors and/or behavioral correlates, where we did not expect to find it."

Follow Tanya Lewis on Twitter and Google+. Follow us @livescience, Facebook and Google+. Original article on LiveScience.com.

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Mat Evans / University of Sheffield

A Roomba robot outfitted with whiskers and reprogrammed with monkey smarts determines what type of flooring is beneath it.

The next time you find yourself trapped under a pile of rubble, your savior might be a Roomba — souped-up with whiskers and a monkey brain.

Such a robot was recently shown to outperform other whiskered robots in characterizing its environment, using technology that could wend its way into next-generation search and rescue robots, the University of Sheffiled reports.

Researchers have long known that rats sense their environment with whiskers. But models of how their brains interpret these signals vary. 

One approach, for example, has assumed that rats looked at whisker movement patterns and vibrations over a set period of time and then used that information to make a decision.

But various robots created with this model, Science Now explains, correctly guessed the floor beneath them only 50 to 80 percent of the time, after 0.4 seconds of exposure.

Nathan Lepora at the University of Sheffield in England wondered if outfitting these robots with a model of how the monkey brain makes decisions would be an improvement.

Previous research shows that individual neurons in monkey brains ramp up their firing rates when making decisions about the direction of motion for a group of random dots flashing on a screen.

A decision is made when the firing of these neurons cross a certain threshold. If the neurons responding to the up motion cross the threshold first, for example, the monkey would say the dots are moving up.

Lepora and his team fitted a brain model based on this monkey study into an existing Roomba with rat whiskers and found that it nearly flawlessly correctly identified the type of flooring beneath it.

The findings are reported Jan. 25 in the Journal of the Royal Society Interface.

In addition to improved rescue robots, the result suggests that rat brains may function similar to those of monkeys — in fact, they "suggest the possibility of a common account of decision-making across mammalian species," the team conclude.

[Via: Science Now and University of Sheffield]

More on whiskers, rats, monkeys, and brains:

• Virtual whiskers have the touch
• RatCar takes to the robo-road
• 3-D model of rat brain circuit created
• Cat brain inspires computers of the future
• How whiskers help rats find their way