Image of the Day: Target Practice

Bats move their ears fast to create frequency shifts in echoes that can give them more information about their prey targets or the surroundings they are navigating through.

Chia-Yi Hou
Jun 5, 2019
This image shows great roundleaf bats (Hipposideros armiger) with colors indicating from low values in blue to high values in red: the speed of the ear surface (left), angle between ear motion and incoming echoes (center), and magnitude of the resulting Doppler shift (right).

Researchers report in PNAS that some bat species, including the great roundleaf bat (Hipposideros armiger), are able to move their ears fast to create Doppler shifts, or changes in frequencies due to the relative motion of the source and the detector. The bats may use the self-generated Doppler shifts to gain more information about their prey’s location or the physical environment they are navigating through, according to the report.

X. Yin, R. Müller, “Fast-moving bat ears create informative Doppler shifts,” PNAS, doi:10.1073/pnas.1901120116, 2019.