Days after a poacher's trap killed a young mountain gorilla in Rwanda's Volcanoes National Park in 2012, researchers spotted something remarkable: two four-year old gorillas working together to dismantle similar snares in the area.
"This is absolutely the first time that we've seen juveniles doing that ... I don't know of any other reports in the world of juveniles destroying snares," Veronica Vecellio from the Dian Fossey Gorilla Fund's Karisoke Research Centre in Rwanda told National Geographic at the time.
"We are the largest database and observer of wild gorillas ... so I would be very surprised if somebody else has seen that."
Thousands of these snares are set up by local bush meat hunters to catch antelopes and other animals for eating, and while they reportedly have no interest in primates, young gorillas are sometimes unintentionally caught up and left to die.
The traps work by tying a noose to a branch of bamboo stalk, and bending it down to the ground, with another stick or rock used to hold the noose in place. The whole thing is obscured by dry leaves and branches.
When an animal comes along and unknowingly moves the anchoring rock or stick, the branch flings back up and tightens the noose around it, holding it in place till the poachers come looking. "If the creature is light enough, it will actually be hoisted into the air," Ker Than wrote for National Geographic.
While adult gorillas are large and strong enough to extract themselves, young gorillas often are not, and if they don't die from being stuck in the trap, they run a very real risk of dying from injuries sustained during their escape, such as dislocated bones and gangrenous cuts.
This is particularly bad news, seeing as the gorillas in this part of the word - a subspecies of the eastern gorilla called Gorilla beringei beringei - are now critically endangered, and the population simply cannot sustain the consistent loss of young gorillas to snares.
Vecellio and her team were searching the park daily for these traps and dismantling them, but in 2012, one of the local trackers spotted one near the Kuryama gorilla clan, which had lost one of its juveniles to a trap just days earlier.
The tracker, John Ndayambaje, went to dismantle the snare, but was given a warning signal by the dominant male of the clan to back off.
"Suddenly two juveniles - Rwema, a male; and Dukore, a female; both about four years old - ran toward the trap," Than reported.
"As Ndayambaje and a few tourists watched, Rwema jumped on the bent tree branch and broke it, while Dukore freed the noose."
The two gorillas then reportedly found another snare, and with the help of another juvenile, managed to dismantle that one too.
The researchers suspect that the confidence and speed with which they destroyed the traps means these young gorillas had learnt how dangerous they were, and had dismantled them before.
While a great solution would be to have the researchers go out and teach more gorillas how to dismantle these traps, Vecellio and her team said it would be unethical to mess with the gorillas' behaviour to that degree.
They just have to hope the juveniles continue to spread their knowledge throughout the clan on their own.
"No we can't teach them," she told National Geographic. "We try as much as we can to not interfere with the gorillas. We don't want to affect their natural behaviour."
A version of this story was first published in January 2016.