Two hundred square miles (518 sq km) of tropical rainforest in Colombia are being explored for the first time in over 40 years. Because of a civil war that started in the 1970s and lasted until 2016, biologists had not been able to go there. It was too dangerous. So no one had studied the plant and animal life for decades. Teams of scientists have already discovered possible new species, including a tree-dwelling mouse. Critically endangered species, such as the wax palm, have also been surprising finds.