The experience of watching your groceries slide across a supermarket checkout counter is almost universal. In this everyday process, an electronic device scans the barcode and identifies each product. There’s a technical explanation behind the “beep”: the eyes can’t see it, but the device emits a beam of electromagnetic waves that measures the amount of light reflected back by the item. This signature is unique to each item, allowing us to tell them apart. Known as near-infrared spectroscopy (NIR), the technology is also used to analyze samples of different materials and has many applications: for quality control in agriculture, or for monitoring blood oxygen levels in the medical field. Would it be possible, then, to reproduce this common scanning practice to identify species in tropical forests, such as the Amazon? Science has the answer. As the sun sets, the dense green area of the Mamirauá Sustainable Development Reserve in Brazil’s Amazonas state darkens in the blink of an eye. With the disappearing of the light comes the buzzing of carapanãs, as the various species of mosquitoes are called in this region. The noise accompanies Kelly Torralvo, a senior researcher in the Terrestrial Vertebrates Ecology Research Group at the Mamirauá Institute. Walking slowly along a trail with her flashlight, she searches for reptiles and amphibians among branches and leaves. She collects the animals and takes them back to the laboratory at the field base located in the reserve. There, with the help of a device that uses NIR technology, researchers “scan”…This article was originally published on Mongabay