University of Bonn’s Zoology Prof. Dr. Helmut Schmitz, along with Dr. Herbert Bousack from the Peter Grünberg Institut at the Forschungzentrum Jülich conducted a forensic research.
Schmitz studied fire beetles belonging to the genus Melanophila and their advanced IR sensors. The pyrophilous insects use the sensors to detect forest fires. It is a major ecological niche.
Assisted by the Technische Universität Dresden, and Forschungszentrum caesar in Bonn, the researchers have hypothesized this professed photo-mechanical beetle infrared sensor, by conducting technical reconstruction of this natural prototype. The beetles' IR receptors include tiny cuticula spheres measuring 0.02 mm. When filled with water, it efficiently absorbs IR radiation. Expansion of water due to heating up leads to pressure fluctuation, which is detected by mechano-sensitive sensory cells of increased sensitivity.
The sensor’s sensitivity can be determined by incorporating mini transmitters to Melanophila beetles to explore forest fires. The distance across the burnt area helps assess the minimum heat radiation necessary for attracting the beetles. Due to its small size, the beetles cannot transport a transmitter for long distances.
Reports based on the August 1925 burning of large oil depot in Coalinga, California states that large number of charcoal beetles (Melanophila consputa) were attracted towards the huge blaze. As the Central Valley of California was forest-less the beetles must have travelled from afar. Prof. Schmitz says that beetles multiply in burnt areas.
An engineer at Peter Grünberg Institut at the Forschungszentrum Jülich, Dr. Herbert Bousack conducted statistical analysis for modeling the sensitivity of the sensor. The simulation was mostly performed based on the Coalinga fire. Dr. Bousack found the beetle sensor to be highly sensitive. The beetles depend on stochastic resonance; their infrared sensors are capable of sensing the signals even under low level of thermal noise. Furthermore, sensors of pyrophilous Melanophila beetles have increased sensitivity than commercially-available uncooled infrared sensors. Further upgrades and more efforts will lead to better implementation of this natural prototype for developing early-warning systems for forest fires.