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How do apes and humans differ? There are a lot of answers, but one way is communication! Esther Hermann and Michael Tomasello conducted research to test an ape’s ability to understand a human’s communicative motive. To do this they took a look at how an ape interprets pointing. Additionally, the researchers did the same tests to children (18 and 24 months old) and compared the results of the apes to the children!

Hermann and Tomasello used two conditions in their study: informing and prohibiting. The informing condition determined whether the subjects understood a cooperative relationship, while the prohibiting condition determined whether the subject understood a competitive relationship.


Ten chimpanzees and two bonobos were studied using the setting seen in the picture to the right. The hiding spot on the sliding platform is where food would be hidden. The experimenter would point to the cup with the food during each trial.

Each subject first went through a warm-up to make sure they understood what to do. After the warm-up, two experimenters established a relationship with the ape. One was a cooperative relationship for the informing condition, while the other was a competitive relationship for the prohibiting condition, then the trials began.

In the informing condition the experimenter,

  • pointed to the container with food
  • said in a positive tone, ‘Look here
  • alternated looking at the cup and the ape

In the prohibiting condition the experimenter,

  • gestured toward the container with food and in a negative tone said, ‘No, don’t take this one!
  • avoided eye contact with the ape by staring at the container
  • would bang on the glass and pretend to be angry if the ape retrieved the food!

The graph below shows the apes’ combined group scores. Looking at the graph, we see that the apes significantly found more food in the prohibiting condition than in the informing condition. The study concluded that these results suggest apes do not understand a cooperative or friendly cue in the context studied.


The second part of the study evaluated 48 children, half being 24 months old and half being 18 months old. For the children, the set up included a table with boxes, 2 experimenters, and the child’s mother (Figure to the right). A toy was then hidden under a box for the child to find.

The children also went through a warm-up, where the experimenters played with the children so they could be familiar with one another, as well as learn what to do before the trials started. During the trials, experimenter 1 hid the toy, gave an informing or prohibiting cue, and left the room. The child was then able to choose a box by approaching and opening it.

In the informing condition the experimenter,

  • would hide the toy,
  • with a positive tone say, ‘Look here‘,
  • then would alternate looking at the child and the box with the toy

In the prohibiting condition the experimenter,

  • would talk to herself about a toy she was holding, then place it under a box
  • would then give a gesture and in a negative tone say, ‘No, don’t take this one!
  • looked at the box to avoid eye contact with the child

The graph below shows the average percent correct (choosing the box with the hidden toy) for the informing and prohibiting conditions of the children. Looking at the graph, we can see that the 24-month-old children significantly found the toy more in the informing condition than the prohibiting condition, while the 18-month-old children significantly found the toy more in the prohibiting condition!

The study concluded that these results suggest younger children more closely resemble the apes (better comprehension for the prohibiting or competitive condition), while older children are able to comprehend the informing or helpful cue.

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What does this research mean?

This research supports the idea that apes possess more skills in competitive than cooperative contexts. It also supports the idea that humans are able to interact and understand each other in ways apes cannot. That being said, we must remember not every study can account for every single factor that may influence a decision. Therefore, there are limitations in this study.

For example, when conducting the trials, the child is held in their mother’s arms while the ape is secluded. This creates 2 different environments, where the child may get to feel more comfortable with its mother, while the ape is aware of its solitude. Additionally, this study combined results of 2 different ape species (chimpanzees and bonobos), both of which have different characteristics, personalities, and cognitive abilities.

This study provides great information on how apes and children may think and make decisions. But there is still more research to be done and science continues to ask, “What can these creatures do?”

To read the study in full follow the link below.

Apes’ and children’s understanding of cooperative and competitive motives in a communicative situation

Author: Courtney Lewis

Editor: Joclyn Villegas

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