Why chimps throw poop

What stench through yonder nostrils break? Why would an army of monkeys pelt you with their poop? That's the question we will attempt to answer. Although there are reports of individual differences in aimed throwing in wild and captive apes, to date there has not been a single study that has examined the potential neuroanatomical correlates of this very unique tool-use behaviour in non-human primates.

In this study, we examined whether differences in the ratio of white WM to grey matter GM were evident in the homologue to Broca's area as well as the motor-hand area of the precentral gyrus termed the KNOB in chimpanzees that reliably throw compared with those that do not. We found that the proportion of WM in Broca's homologue and the KNOB was significantly higher in subjects that reliably throw compared with those that do not.

We further found that asymmetries in WM within both brain regions were larger in the hemisphere contralateral to the chimpanzee's preferred throwing hand. We also found that chimpanzees that reliably throw show significantly better communication abilities than chimpanzees that do not.

These results suggest that chimpanzees that have learned to throw have developed greater cortical connectivity between primary motor cortex and the Broca's area homologue.

It is suggested that during hominin evolution, after the split between the lines leading to chimpanzees and humans, there was intense selection on increased motor skills associated with throwing and that this potentially formed the foundation for left hemisphere specialization associated with language and speech found in modern humans.

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Neither your address nor the recipient's address will be used for any other purpose. The information you enter will appear in your e-mail message and is not retained by Phys. You can unsubscribe at any time and we'll never share your details to third parties. It's yet another reason they will never make a good pet. While the species is still prone to throwing things, they usually stick to rocks or branches when they want to express their annoyance.

Ease of access is not the only reason a chimpanzee will launch feces. When a chimp is in captivity, throwing poop is likely to cause a reaction—either from zoo employees or guests. Chimps will begin to associate the act throwing fecal matter to a response usually surprise or horror.

In tossing their crap, chimps realize that they can control the behavior of others to some degree. If they throw an overhand turd, people will run.

By choosing I Accept , you consent to our use of cookies and other tracking technologies. Spanish La Liga View team list. Filed under: Animals. Chimpanzee throws poop directly into grandma's face New, comments.