New findings show that chimpanzees change the way they hunt when they know that humans are watching them.
Biologists who have been studying two groups of chimps for a number of years now admit that their work may have disrupted the monkeys' usual way of hunting. One group, called “Sonso”, hunt for colobus monkeys in small groups. Meanwhile, members of the other group, called “Waibira”, hunt alone and hunt for anything they can catch. The scientists say that the chimps are supposed to hunt for colobus monkeys in groups. The Waibira group, obviously, has deviated from this.
Scientists generally do their best not to disrupt or cause harm to the objects of their study. Of course, there are times when unforeseen circumstances may arise. In this case, it's possible that the chimpanzees in the Waibira group may be less familiar with the presence of the scientists.
According to the study, these findings are a testament to how sensitive chimps are to human presence. The researchers expected both Sonso and Waibira groups to go after the same prey since both groups share a territorial border. Thus, it would have made sense for both groups to have the same food sources. However, the chimps went after different kinds of prey in different ways.
Researchers think that this difference may lie in how accustomed the chimps are to human presence. Most of the adults in the Sonso group, for example, grew up with the scientists following them around in the forest. The scientists had only been following the Waibira group for about five years, which is just a fraction of the lifetime of the 30- to 40-year-old adult chimps in the group. The younger Waibira chimps, however, have grown comfortable with the presence of the researchers.
Apparently, other researchers in other areas have observed a similar pattern in the changing of hunting habits due to their presence. It's possible that this happens because chimpanzees are territorial and wary of newcomers to their area. Consequently, they have a difficult time accepting strange humans into their domain and their everyday lives. This may be what's driving the changes in their hunting habits.
An important question to ask, of course, is if it's absolutely necessary for researchers to physically be in the chimps' space. Even though the chimps get used to the researchers over time, their presence is obviously distressing or disruptive if it can push the animals into changing their behavior.
Close observation of chimps can help researchers understand more about human language and social structures. However, is it really worth it? Is it necessary for human researchers to come into the chimps' territory and make them uncomfortable?
The answer, possibly, is no. The presence of researchers right there on the ground used to be necessary, but technology can now take their place. There are camera traps and microphones that scientists can make the most of. These will not force the chimpanzees into situations that they are unfamiliar and uncomfortable with. After all, minimizing the impact on the object of the study is an important part of a researcher's work.
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