“I thought, my God, this is like someone’s discovered another continent!” says Brian Brown, an entomology curator at the Natural History Museum of Los Angeles County. He was talking about insects.

When studying insects in the Amazon, most entomologists cast their eyes down, to the intricate pathways of moss and underbrush that make up the rainforest floor. But José Albertino Rafael wanted to look up. Really far up—to more than 105 feet in the canopy. 

During two weeks in 2017, Rafael, an entomologist at Brazil’s National Institute of Amazonian Research, and colleagues trapped insects at various heights, starting at ground level, from a 131-foot tower erected in the middle of the Amazon, just outside Manaus.

The findings were staggering, says Brown, who was part