Just Like Humans, Apes Show Emotion

Some of our closest animal relatives, the chimpanzee and the bonobo, aren't just biologically similar. Whether it's letting out a groan or hitting things when angered or disappointed, apes act in similar ways to humans when frustrated.

According to researchers at Duke University, when apes face a longer wait for food or a disappointing meal of plain lettuce instead of fruit, it can result in tantrums including loud screaming, moans and hand banging. It is true that most adults can contain their emotions when life presents problems. However, researchers say these feelings and urges to express them are “rooted in our evolutionary past” and play an instrumental role in decision-making. To explore the link between human and ape mental processes, Duke University researchers conducted a series of experiments with apes.

In an experiment with 23 chimpanzees and 15 bonobos, each ape was faced with multiple food-related problems. In one situation, apes were given the choice between a small and large portion of papaya. To obtain the larger portion of food, the apes were required to wait three minutes more.

In another experiment, apes were presented with a small portion of food or a mystery option ranging from disappointing lettuce to crowd-pleasing banana slices. Some apes chose the small portion of food rather than risking ending up with a food they didn’t like in the gamble. However, those that did pick the more daring option showed either positive or negative feelings based on the resulting snack. When the mystery option was of lesser value than the original option, apes threw tantrums or attempted to exchange. When the choice worked in their favor, there were few complaints.

According to the authors of this study, emotions help humans and apes guide decision-making. This study on ape behavior can show how even though humans have evolved, we still have more similarities with apes than we might think.

[Source: Chicago Tribune]