Have you heard the buzz? By fitting hundreds of bumblebees with tiny QR codes that tracked their movement, biologists from Harvard University say they’ve learned how pesticides negatively affect colonies. Researchers observed dramatic changes in bees’ behavior after being exposed to neonicotinoids — the world’s most common class of insecticide. Affected bees were less social and energetic, spending less time caring for their young and regulating nest temperatures by fanning their wings. Biologists hope the study’s high-tech surveillance system could eventually be used to test pesticides more effectively.