It is also important to test other ape populations of the same species to see how widespread this ability is among other individuals within the species.įrom a cognitive point of view, it is unclear whether apes would have also solved the task if the peanut had not already been floating in the water. This information is crucial to making inferences about the evolution of cognitive flexibility in nonhuman primates and humans. From a comparative point of view, it is unknown whether other species of great apes would be able to solve the task. Nevertheless, orangutans using water to get a peanut from the bottom of a tube is a phenomenon that deserves further examination. However, the information gathered from those experiences still had to be cognitively reorganized/re-used to solve a problem that they had never faced before: a peanut at the bottom of a tube. It is very likely that those experiences were instrumental in allowing subjects to solve the floating peanut task. Moreover, orangutans were familiar with shelled peanuts and they might have even seen them floating in water. It is very likely that orangutans had multiple experiences with liquids in their mouths and even spat them at objects or other individuals. Although the idea of insight has been criticized because prior experiences may have played a role in the solution, Köhler himself, recognized that experience with objects preceded their insightful use. įurthermore, two elements suggest that this was a manifestation of insightful behavior, : First, the sudden appearance of spitting into the tube after a period of unsuccessful attempts which did not involve spitting in any way and second, the immediate appearance of spitting when needed without reverting to previous unsuccessful behavior. For orangutans on the other hand, water spitting of this sort is not known to be a natural, species-typical behavior, nor did it play any role in the special living conditions of that particular zoo population tested by Mendes and colleagues. There is no reason to assume that much more cognitive flexibility is involved for example, it has never been reported that archerfish are capable of using their “spitting behavior” in a completely different and new context. These data suggested that their spitting was goal-directed and performed to remove the peanut from the tube.Įven though archerfish ( Toxotes jaculatrix) are also known to spit water streams to catch their prey, most of the spitting behavior seems to be hard-wired, with only some details being amendable to change (i.e., timing and/or direction of spits. In particular, orangutans did not spit water into an empty tube upon encountering a peanut that was out of reach (in front of the tube). Additionally, control conditions demonstrated that spitting inside the tube was not a general response that subjects displayed upon encountering an out-of-reach reward. ![]() Releasing water from their mouths into the tube raised the water level and brought the peanut within reach. Recently, Mendes, Hanus and Call reported five orangutans repeatedly spitting water into a tube to retrieve a peanut that was floating at the bottom of the tube in a small amount of water. The vast majority of tools used by animals consists of solid materials or are constructed from them. Reports of such behavior originate from natural observations – as well as from experimental studies –. Within the oldest group (8 years), 58 percent of the children solved the problem, whereas in the youngest group (4 years), only 8 percent were able to find the solution.Ī variety of sophisticated tool-using behavior is known to occur in several vertebrates, including birds and mammals –. ![]() Finally, we tested how human children of different age classes perform in an analogous experimental setting. We found suggestive evidence for the view that functional fixedness might have impaired the chimpanzees' strategies in the first experiment. Another experiment was conducted to investigate the reason for the differences in performance between the unsuccessful (Experiment 1) and the successful (Experiment 2) chimpanzee populations. Additional controls revealed that successful subjects added water only if it was necessary to obtain the nut. Twenty percent of the chimpanzees but none of the orangutans were successful. In order to better understand the cognitive demands of the task, we further tested other populations of chimpanzees and orangutans with the variation of the peanut initially floating or not. Here, we tested chimpanzees and gorillas for the first time with the same “floating peanut task.” None of the subjects solved the task. described the use of a liquid tool (water) in captive orangutans.
0 Comments
Leave a Reply. |