Scientists have found the heat-sensing mechanism used by vampire bats to detect their next meal, according to a report in the journal Nature.
The bats – utilizing what are essentially infrared sensors – can then pinpoint the highest concentration of blood closest to their prey’s skin so they can feed more efficiently.
"Vampire bats feed on blood, and it's useful for them to have an infrared detector to be able to find the circulation," said David Julius, PhD, the Morris Herzstein Chair in Molecular Biology & Medicine at the University of California, San Francisco, who led the research.
By studying wild vampire bats in South America, researchers at the UCSF and the Instituto Venezolano de Investigaciones Científicas in Caracas, Venezuela were able to identify the special biological process: a sensitive, heat-detecting molecule found in vampire bat noses called TRPV1.
The researchers are now hoping the find can aid the development of a new class of pain medications that target molecules like TRPV1 – the same molecule involved in pain sensation, such as that associated with touching a hot object, or hypersensitivity to heat after injury and inflammation – as occurs with sunburn.
"There is a double-edged sword with pain," Julius said. "Pain is necessary as a warning system to let us know when we are in danger of injury but, at the same time, pain can outlive its usefulness as a warning system when it fails to resolve and becomes chronic and debilitating."
According to Julius, the discovery highlights how even small changes to genes in the genome of a species can contribute to major evolutionary adaptations over time – in this case, giving vampire bats the ability to detect infrared heat.
Vampire bats are the only known mammal that survives solely on blood, and they need to drink it pretty much every day to survive, supporting this need through a number of helpful evolutionary adaptations.
Researchers have known for years that pits on vampire bats' noses allow them to detect blood vessels because they radiate heat. But no one knew exactly how this occurred.