Vampire bats recognize individual prey by the unique sounds of the preys breathing according to a study in BMC Biology. Researchers examind the ability of vampire bats to detect breathing cues from prey items.
This is how it was done:
Vampire bats were trained to discriminate three sequences of breathing sounds recorded from three different subjects. A spectrogram of a recorded breathing sound is shown in Fig. 2. Once the vampire bats had learned this task, additional breathing sounds, recorded under different experimental conditions from the same three subjects, were randomly interspersed. The spontaneous association of these test sounds with the learned training sounds was assessed.
Results indicated that vampire bats were significantly better at this association than humans were. The researchers suggest they may be effective at this (depending on masking sounds) at up to tens of meters.
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