A Park Ranger Comforts A Sad Gorilla That Just Lost His Mother
The gorilla appears to be showing his appreciation for the sympathy by placing his hand on the ranger's leg.

This gorilla, like the other three orphans currently living in the sanctuary, were brought there after their parents were killed by poachers or as a result of illegal attempts by traffickers to smuggle them out of the park.
With more than 200 mountain gorillas, Virunga National Park accounts for about a quarter of the world's mountain gorilla population.
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