The findings appear in the Sept. 7 issue of the journal of Science. The work was led by Justin Wood, a graduate student in the Department of Psychology in the Faculty of Arts and Sciences at Harvard, with David Glynn, a research assistant, and Marc Hauser, professor of psychology at Harvard, along with Brenda Phillips of Boston University.
“A dominant view has been that non-human primates attend only to what actions 'look like' when trying to understand what others are thinking," says Wood. "In contrast, our research shows that non-human primates infer others' intentions in a much more sophisticated way. They expect other individuals to perform the most rational action that they can, given the environmental obstacles that they face."
The scientists studied the behavioral response of over 120 primates, including cotton-top tamarins, rhesus macaques and chimpanzees. These species represent each of the three major groups of primates: New World monkeys, Old World monkeys and apes. All three species were tested in the same way, and the results showed the same responses among the different types.
In the first experiment, the primates were presented with two potential food containers, and the experimenter either purposefully grasped one of the containers, or flopped their hand onto one of the containers in an accidental manner. For all three species, the primates sought the food container that was purposefully grasped a greater number of times than the container upon which the hand was flopped. This indicates that the primate inferred goal-oriented action on the part of the experimenter when he grasped the container, and was able to understand the difference between the goal-oriented and accidental behavior.
In the second experiment, the researchers asked if the primates infer others' goals under the expectation that other individuals will perform the most rational action allowed by the environmental obstacles. Again, the primates were presented with two potential food containers. In one scenario, an experimenter touched a container with his elbow when his hands were full, and in another scenario, touched a container with his elbow when his hands were empty. The primates looked for the food in the container indicated with the elbow more often when the experimenter's hands were full. The primates considered, just as a human being would, that if someone's hands are full then it is rational for them to use their elbow to indicate the container with food, whereas if their hands are empty it is not rational for them to use their elbow, because they could have used their unoccupied hand.
Developmental psychologists have long understood that young children are able to engage in this type of rational action perception, but scientists have not understood if this ability is unique to human beings, or shared with other animals. This study suggests that this ability evolved as long as 40 million years ago, with non-human primates.
“This study represents one of the broadest comparative studies of primate cognition, and the significance of the findings is reinforced by the fact that these results were consistent across three different species of primates,” says Wood. “The results have significant implications for understanding the evolution of the processes that allow us to make sense of other people's behavior.”
Amy Lavoie | EurekAlert!
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
Pollen taxi for bacteria
18.07.2018 | Technische Universität München
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Life Sciences
18.07.2018 | Materials Sciences
18.07.2018 | Health and Medicine