IN PHOTO:A bonobo, a type of chimpanzee, reacts during feeding time at Twycross Zoo, central England July 28, 2008. Reuters/Darren Staples

A new study has shown that chimpanzees can produce facial expressions as a way to communicate their emotions, Portsmouth News reports. According to researchers from the University of Portsmouth, the primates’ way of communication shares something in common with the humans’ than initially thought.

Lead researcher Marina Davila-Ross of the Centre for Comparative and Evolutionary Psychology in the university said that the study showed the evolution of the facial expression from ape to human. In the study published in PLOS One, researchers videotaped 46 chimpanzees at the Chimfunshi Wildlife Orphanage located in Zambia.

The subjects belonged to the age range of two to 35 years old. The report states that half of the chimpanzees were born in the wild and rescued as orphans to the sanctuary. The rest of them were bred in the sanctuary.

The study used a program called ChimpFACS, which is a facial action coding system designed for the primates that measures their facial movements. According to the Kim Bard, designer for the program, in the news report, the coding system will allow them to examine any slight facial movements.

The researchers then compared both human and chimpanzee facial expressions “based on their shared musculature”. The published report collected data from June to August 2007.

The study looked into specific types of smiles that come with sounds of laughter and found that these smiles originally evolved in human smiles produced when laughing. The findings suggest that these types of smiles in humans may have evolved from expressions made by ancestral apes.

Furthermore, the study notes that future research should look into the relationship between production of “facial expressions and vocalizations of nonhuman primates”. While the study suggests that facial expressions existed way before humans evolved, Davila-Ross said that there were still main differences between humans and ape ancestors.

To report problems or leave feedback on this article, email: