Two baby chimps, Felix and Mara, were adopted by Lwiro Primates Rehabilitation Center in the Democratic Republic of Congo (DRC) after their families were poached for bushmeat or the exotic pet trade, the institution announced in a Facebook post on Monday.
"Different day, same story—just like that, these babies have lost the only home they knew," explained the post.
This trauma was so great, staff in the center have said, it caused Felix's eye color to change. Staff at the center believe Felix was beaten, leaving a severe ulcer in his right eye, while the brown hair on his body suggests he experienced severe malnourishment.
"As you can see, the discoloration in one of his eyes is because of trauma," a health update published on Tuesday stated.
While changes to eye color are rare, it can happen—in humans as well as in primates.
"The factors that can cause eyes to change colors—or appear to have different colors—include genes, diseases, medications and trauma," Omar Chaudhary, MD, an ophthalmologist in Potomac, Maryland, said in an article for the American Academy of Ophthalmology.
This change in color may relate to the iris or other parts of the eye that can make it appear that the color of the iris is different. One way trauma can change eye color is through uveitis, an inflammation of eyeball's middle layer. Another way is through tissue loss, which can make the iris appear as though it is a different color.
Felix isn't the only one showing physical signs of the ordeal they'd been through. Mara still has bags under her eyes, suggesting she is malnourished and dehydrated.
"Psychologically, she has been very untrusting of humans, and also not as playful as Felix," staff said.
It is not known exactly what happened to Felix and Mara's family but chimps like these are often taken by poachers to feed the market for exoctic pets. According to the BBC, a baby chimp can fetch up to $12,500 on the international market.
Tactics adopted by poachers do not just target the baby chimp, but the entire chimp family who might try to resist the poaching. The prize of one (alive) baby frequently involves the slaughter of up to 10 adults, the BBC reports. They are then often sold for bushmeat.
While the pair may have had a traumatic start to the month, if an update posted on Tuesday is anything to go by, they seem to be adapting well to their new surroundings.
"After a very stressful yesterday, we want to start today by giving some good news—unlike many other babies that we've got before, Felix & Mara are eating and sleeping very well. They're also being playful with each other, and have become very trusting and needy of their human surrogate mamas," the post stated.