Farmers can use drones to monitor their fields, but they have their limits when they can rarely fly for more than 20 to 30 minutes at a time. University of Washington researchers might have a smarter way: recruit some insect friends. They've developed sensor backpacks that are light enough (about 0.0035 ounces) and efficient enough to ride on a bumblebee, but capable enough to collect data for seven hours at a time over relatively long distances. You wouldn't have to replace packs very often, either, as they could just fly into their hives to wirelessly recharge and transmit data. The trick was to find a way to track the bees' locations without using power-hungry GPS.