The amazing spider monkey

It was once a monkey who was endangered in the rainforests but with its prehensile tail acting like a 5th limb it was able to out maneuver any predator trying to attack it and It travels in groups of 30 or so but when food gets scarce they break into groups of 3. It nearly all came crashing down for the spider monkey when the inland rainforest turned to savannah but so did it. The spider monkey now has a venomous tail able to incapacitate and predators and even kill some smaller animals. It went from a brown color to blend into trees where they used to nest to know a beige color know because they burrow into the ground. They have nocturnal eyes so they sneak out at night to avoid predators and they use there great hearing to use echo location to scan for predators in the savannah.