We all know the tale of Disney's Tarzan, where a female gorilla named Kala takes in an orphaned human baby after his parents were attacked and killed by a leopard. And while that may seem a bit far fetched, at least one chimp has adopted her best girlfriend's orphaned newborn.

The newborn chimpanzee named Boon was recently born at the Monarto Zoo in Adelaide, Australia, but was orphaned soon after his mother, Soona, died while giving birth. Since then, he has been adopted by his mother's closest friend, Zombi. She's expecting a child of her own but even remained at Soona's side as she passed away. Now the mom-to-be has jumped into the role early to help her son grow healthy and strong, according to Discovery

Chimpanzees are humans' closest living relatives and while we have evolved along different paths for millions of years, scientists continue to explore our similarities. But is altruism one of them? 

"I'm humbled by what we've seen from the chimpanzee troop over the last few days. It's unheard of to see a heavily pregnant chimpanzee adopt an orphaned newborn infant," Laura Hanley, senior primate keeper at the zoo, told the Daily Mail. "The unique situation certainly reinforces the strong bond our chimps share and the similarities these amazing creatures have with their closest living relative - us." 

While Zombi's behavior is extremely rare, researchers from the Max Planck Institute in 2010, have documented  at least eighteen cases of chimps adopting orphans in the wild – cases where newborns and very young chimps had lost their mothers due to multiple causes, mostly predation and injury. This studyalso  revealed that both male and female caregivers devoted much time and effort protecting their adopted young. 

Zookeepers back at Monarto Zoo don't believe that taking care of Boon will jeopardize Zombie's ability to take care of her own child once it's born within the coming weeks. Still, they promise to monitor her closely to make sure she can manage both babies.  

"We can't completely predict the outcome, but we know if any chimp can look after two infants at once, Zombi can," Hanley said, "When the time comes for her to have her own infant, we'll let nature take its course and only intervene if Zombi appears to be struggling or if the infants require supplementary feeding."

The staff at Monarto Zoo is saddened by the loss of Soona, but they are also very grateful that Boon has been able to survive such an ordeal, explained Elaine Bensted, the zoo's chief executive.

"The last few days have been a whirlwind of emotion, but the silver lining is that our little Boon is doing incredibly well considering his rough start to life," Hanley added.  "From the minute she [Zombi] first cradled the newborn, she's been amazing - grooming, supporting and nursing the little man as though he was her own."

Boon can now be seen by the public with the rest of the troop living in the zoo's chimp enclosure. 

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