Natures wonders: how bat echolocation works (Introduction)

by David Turell , Wednesday, March 09, 2022, 16:40 (779 days ago) @ David Turell

More discoveries of how the ability is used:

https://www.smithsonianmag.com/science-nature/five-amazing-adaptations-that-help-animal...

"Bats aren’t blind at all, in fact they can see as well or better than humans, particularly when light is low around dawn and dusk. But the flying mammals are justly known for the way they rely on their mouth, nose and ears to get around at night by the process of echolocation. Bats emit sound waves from their mouths or nostrils at ultrasound frequencies. These bounce off objects, even those as thin as a human hair, before returning to the bats’ ears. The feedback allows bats to map their surroundings and deftly navigate between trees or snare a mosquito in midflight. The system works so incredibly well that bats can use approach angles to identify and snare a small bug that’s sitting on a much larger leaf, without the leaf’s larger echo obscuring their smaller prey.

"But scientists have recently learned that echolocation also plays an important role in bat social life. The calls bats use contain information including sex, age or even individual identity.

"Using behavior experiments Jenna Kohles and colleagues recently demonstrated that some bats can even use this identity information while they’re flying and searching for prey.

“'They can tell their group members apart from one another using just the “individual signatures" contained in the echolocation calls they use to search for insects,” says Kohles, a behavioral ecologist at the Max Planck Institute of Animal Behavior. “So the social lives of bats flying around at night are likely to be much more complex than previously thought.'”

From the actual study:

“'We played echolocation calls from two different bats that were both group members of the subject bat,” Kohles said. “By measuring the responses of the subject bats as we switched between calls from different individuals, we could learn about whether the bats perceived differences and similarities between the calls.”

"They found that the bats indeed distinguish between different group members, likely by using individual signatures encoded in the calls. Their results could mean that search-phase calls serve a double function. They not only help bats detect prey, but also convey individual identities to nearby foraging group members. This coincides with the fact that the majority of M. molossus’ auditory cortex is tuned in to these search-phase calls, indicating the importance of processing them.

"This finding offers insight into not only the social strategies these bats may use to meet their energetic needs, but also into the evolution of echolocation signals and social communication in bats.

“'This study suggests that we may be underestimating the crucial ways social information influences bat foraging success and ultimately survival,” Kohles said."

Comment: Bats present the same problems as whales. The required adaptations are so complex and so intertwined, only design is the answer.