New footage from an undercover robot baby gorilla has given filmmakers a behind-the-scenes look at the lives of a pack of Ugandan Silverback Mountain gorillas.

The gorillas were caught on camera as they sang during their dinner, a behavior that has never before been captured.

However, after finishing their meal and their hummed arias, the video also revealed how gassy the gorillas became after eating, as clear evidence of flatulence could be heard in the video. Gorillas consume 40 pounds of sustenance per day.

2 YOUNG GORILLAS SEEN EMBRACING IN ADORABLE MOMENT

The rare video of the gorilla choir is featured in a segment of the PBS series "Nature: Spy in the Wild 2," which trails animals in their natural habits by using robotic look-alikes of the animal being observed.

Human camera operators typically must keep a safe distance from wild gorillas.

In this photo taken Friday, Sept. 4, 2015, members of a family of mountain gorillas named Amahoro, which means "peace" in the Rwandan language, take a rest in the dense forest on the slopes of Mount Bisoke volcano in Volcanoes National Park, northern Rwanda. Deep in Rwanda's steep-sloped forest, increasing numbers of tourists are heading to see the mountain gorillas, a subspecies whose total population is an estimated 900 and who also live in neighboring Uganda and Congo, fueling an industry seen as key to the welfare of the critically endangered species as well as Rwanda's economy. (AP Photo/Ben Curtis) (The Associated Press)

According to the show's producer Matt Gordon, the team chose not to construct an adult gorilla spy because the pack might see it as a threat.

Instead, the animatronic baby gorilla was designed to be able to move and close its eyes, as well as beat its chest. Wild gorillas are known to communicate with each other through eye contact. The young gorilla robot was also capable of averting his gaze when needed, to show respect to the real gorillas, as real young gorillas would do.

Additionally, the PBS team devised the "spy gorilla" to portray a submissive disposition in the hope that the pack would warmly welcome it.

They were also able to capture a rare moment of a baby gorilla running up to the robot and beating its chest. Such behavior would have been hard to observe using traditional methods, Gordon said.

In 2016, researchers confirmed that gorillas sing to themselves while eating, recording audio of behavior that had long been anecdotal. The scientists observed western lowland gorillas in a protected forest in the Republic of Congo and published their findings in the journal PLOS ONE.

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The study's authors also learned that older gorillas performed mealtime humming and singing more than young gorillas, that males "sang" more often than females did, and that gorillas were more likely to sing while eating aquatic plants and seeds rather than insects.

Other episodes in the new series feature a spy macaque taking a hot spring bath in Japan, a spy seal diving near South Africa, a spy polar bear bounding through sea ice near Norway, and a tiny spy hummingbird taking flight alongside thousands of butterflies in Mexico.