Smelly footprints left by bumblebees can help them find good sources of food. The insects secrete invisible markers when they touch their feet on a surface, which can be detected by themselves and other bumblebees.

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Smelly footprints left by bumblebees can help them find good sources of food. The insects secrete invisible markers when they touch their feet on a surface, which can be detected by themselves and other bumblebees.