Saturday, 22 May 2010

Chimpanzees : learning and language


Here is the abstract of a very interesting article written by Victoria Horner1, Darby Proctor1, Kristin E. Bonnie, Andrew Whiten, Frans B. M. de Waal, about some social aspects in learning, for chimp. The (free access) article can be read here : Prestige Affects Cultural Learning in Chimpanzees.

Humans follow the example of prestigious, high-status individuals much more readily than that of others, such as when we copy the behavior of village elders, community leaders, or celebrities. This tendency has been declared uniquely human, yet remains untested in other species. Experimental studies of animal learning have typically focused on the learning mechanism rather than on social issues, such as who learns from whom. The latter, however, is essential to understanding how habits spread. Here we report that when given opportunities to watch alternative solutions to a foraging problem performed by two different models of their own species, chimpanzees preferentially copy the method shown by the older, higher-ranking individual with a prior track-record of success. Since both solutions were equally difficult, shown an equal number of times by each model and resulted in equal rewards, we interpret this outcome as evidence that the preferred model in each of the two groups tested enjoyed a significant degree of prestige in terms of whose example other chimpanzees chose to follow. Such prestige-based cultural transmission is a phenomenon shared with our own species. If similar biases operate in wild animal populations, the adoption of culturally transmitted innovations may be significantly shaped by the characteristics of performers.


It is believed that language is the privilege of the human species. Well, this belief may be wrong :

Saturday, 1 May 2010

Mirror Neurons observed in human action.

In Current Biology, a nice study of mirror-neurons (about mirror neurons). Mirror-neurons were directly observed in certain species of primates, but not in humans. Here is a study that shows, as believed previously to this experiment, that mirror-neurons fire when a human acts and when he/she observes another human acting : Single-Neuron Responses in Humans during Execution and Observation of Actions.