Study of the food-searching activity by smell in diving beetles of Cybister Curtis, 1827 and Hydaticus Leach, 1817 (Coleoptera: Dytiscidae) including the use of a microwave Doppler radar

To investigate how four species of Cybister Curtis, 1827 and one species of Hydaticus Leach, 1817 (Coleoptera: Dytiscidae) detect food, insects were provided with dried sardines using traps made by a three-dimensional printer. More than 83% of the beetles found the sardine hidden in the trap. When the two traps were set in an aquarium-one contained a dried sardine before extraction with boiled water, and another contained a dried sardine after extraction-more than 90% of beetles were caught in the trap with the sardine before extraction. In contrast, less than 3% of beetles entered the trap with the sardine after extraction. No feeding preference was found between the sardines before and after extraction. A microwave Doppler radar was used to quantitatively detect the behaviour using broth extracted from the sardines, and the broth enhanced the food-searching activity. These results suggest that these beetles use smell to find food, and their searching activities are induced by smell.

Automated summary

The study investigates how certain species of beetles detect and search for food using smell. The experiment shows that the beetles are able to find hidden food using their sense of smell and their searching behavior is induced by smell.