Life comes in all shapes and sizes, even among creatures of the same species. But how do animals treat those that are different? Well, footage has been released that answers that very question.

Keepers were worried about the chimpanzees. They weren’t like the others in the zoo, and that very fact might have a significant impact on their integration. So as the other chimps approached the newcomers, the humans prepared for the worst; it could all end violently, after all. Then, they watched open-mouthed as the introductions began.

The chimpanzees in question belonged to Twycross Zoo in Atherstone, England. Twycross first opened its gates in 1963, and since then, it has become known for its large selection of primates. The zoo is home to all the great ape species, in fact, and most notably has a big gibbon population.

However, two unique chimpanzees have ended up as arguably the most famous primates to be hosted at the zoo. They shot to fame, moreover, in 2016 after a video of them was released online, with Jambo and Mongo wowing viewers with their striking looks.

In particular, social media users were stunned by dad Jambo and son Mongo because they were hairless. Their lack of coats also end up highlighting the pair’s impressive musculature, which is otherwise hidden under the hair of chimpanzees.

As for why the father-and-son duo are bald in the first place, it’s down to a condition also seen in humans called alopecia. And while the actual cause of alopecia is still largely unknown in people, it’s understood that the condition is hereditary for Jambo and Mongo.

In addition, as chimpanzees are incredibly close to humans genetically, it’s perhaps not surprising that they would be vulnerable to alopecia, too. But they’re not the only animal species that can be affected by the condition. Dogs, ferrets, cats, rabbits and even mice, for example, have been known to suffer from it.

Yet while a specific ailment is usually the cause of alopecia in animals, that didn’t seem to be the case for the chimps. Regardless, the pair made quite an impression on social media users – and not just because of their hairlessness. The action taking place in the video in which they starred also got them noticed.

That recording, moreover, appears to show the hairless chimps in a violent fight with the other chimpanzees. Certainly, whatever was going on looks quite intense. And that assumption is somewhat confirmed by a comment made by the uploader on the video, who wrote, “A few scratches and some minor wounds and probably a few more scars.”

Initially, the hairless chimps are seen squaring off against the other apes in the troop. Before long, though, the encounter erupts, and the other chimps pursue the fleeing father-son duo. And as tensions seemingly climb higher, the chimps get more physical; soon, in fact, there is seemingly more violent conflict.

At the peak of the “brawl,” moreover, the hairless chimps are right in the thick of the action. There are times, for example, when they appear to be pounding on the backs of the other chimps and literally leaping on them. Then, in the end, Mongo and Jambo are victorious and chase their opponents off.

Apparently, the video shocked some viewers; others even considered the alopecia as a sign of the zoo’s abuse. As a consequence of these reactions, though, Twycross released a statement explaining what was really going on in the video – and it wasn’t quite what concerned watchers may have thought.

Specifically, on March 14, 2016, Twycross Zoo wrote a disclaimer on its Facebook page. “We see that our chimpanzees Mongo and Jambo have taken the internet by storm!” it said. “We’d like to clarify, to put all your minds at rest, that this is completely normal behavior.”

The statement continued, “The behavior shown in the film footage was what we refer to as ‘displaying’ rather than fighting. If you watch closely, there was actually very little physical contact.” Indeed, a closer inspection of the video reveals this to be the case.

Furthermore, the relationships of chimpanzees are actually surprisingly complicated. Chimps live in a hierarchical social structure with a dominant “alpha male” at its head. Troop members also make allies to support them in disagreements, which can make all the difference when challenging the alpha male.

The alpha male doesn’t necessarily even have to be the biggest or strongest chimp around, either; he could be the most cunning, for instance. After all, those in power need to be socially deft, as it’s their job to settle disputes among the troop and keep the rowdy members in line.

Females share a similar social hierarchy, too, with food privileges being rewarded to higher-ranking members. “Chimpanzees display like [they did on the video] to retain their places in the social hierarchy,” Twycross Zoo wrote on Facebook. It also explained that the behavior exhibited is mostly just posturing.

“It is about intimidating the opponent with lots of noise and bluster instead,” the zoo’s statement continued. And the video’s contents are further explained when Twycross revealed the bald chimps’ positions in the troop. “They are both very active members of the social group, with Jambo being the alpha male,” it revealed.

Unfortunately, in the months that followed the hairless chimp duo’s fame, tragedy struck 22-year-old Mongo. And this sad news came to light on July 20, 2016, when BBC News quoted a statement from Twycross Zoo. “Mongo was undergoing a routine health check to investigate his enlarged air sac,” it explained.

The zoo continued, “Although Mongo showed no other outward signs of ill health, the health check revealed that he had an infection… Regrettably, he failed to recover from the anaesthetic.” Understandably, the news of the chimp’s passing was met with sadness from zoo staff and the public alike.

And while the loss of Mongo will surely be felt by Jambo, too, at least he won’t be alone. Indeed, he was even seen in June 2016 on the verge of romance with a female companion. What’s more, the video in which the two found fame shows that, despite their different appearances, bald chimps are treated just like every other member of the troop. And that’s certainly something that humans could learn from.