One of the least explored environments on earth is the canopy of rainforests high above the forest floor among the branches of tall trees is a living web of thousands of plants and animals. It is home for hundreds of birds and reptile, tens of thousands of insects and countless numbers of microbes. Recently, scientists have begun a systematic study of the rainforest canopy, and one of their favorite sites is in Panama where the Smithsonian Tropical Research Institutes operates a crane that gives scientists unprecedented access to this natural world. Living on Earth contributor Bob Carty went up and along for the ride, and sent us this profile of the people who work at the top of the trees.