Manuel Peinado Lorca Updated: Save Send news by mail electrónicoTu name *

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If you are a nocturnal butterfly, and you think that by doing the don Tancredo not you’re in danger, you’re wrong. To catch prey that are difficult to detect, bats orejudos ( Micronycteris microtis ) have developed an elaborate hunting technique: they use the leaves of the trees on which they ambush their prey as “ mirrors acoustic ”.

The evolutionary arms race between bats: and butterfly heteróceras (hereinafter I will refer to them as moths ) is conditioned by the capacity of the first to use a kind of sonar for biological that allows them to detect the latter in complete darkness.

Find out how the apañaban bats to navigate in darkness became one of the great obsessions of the naturalist Italian Lazzaro Spallanzani (1729-1799), whose passion for biology led him to become a priest for mass and pot to guaranteed subsistence.

Spallanzani performed an exciting variety of elegant (and cruel) experiments with bats that enabled him to conclude that, in some incomprehensible way, the bats were seeing with the ears.

Until there could be reached. Faced with the orthodoxy of the scientific era, his experiments fell into oblivion and the research on the orientation of bats was interrupted during a century and a half.

In 1944, Donald R. Griffin published a brief review in Science magazine to communicate their findings about the ability of orientation to blind bats. Griffin, in addition to reclaiming the wisdom of Spallanzani, it is for the honor of having discovered what he called “ echolocation ”.

A sound biological

echolocation is a form of sound biological Griffin explained with the precision of a watchmaker. Bats emit sounds of high frequency (frequency is the number of sound waves generated per second). Then locate prey by listening to echoes generated when their sounds are reflected in them. The frequencies used by bats ranged between 12 and 210 kHz. Given that the human hearing goes away at about 20 kHz, this means that the majority of bats ecolocalizan to much higher frequencies than humans can hear.

Until now it was thought that it was sensually impossible for the bats to find prey, silent and immobile in the disorder of the thick jungles and forests using echolocation. It is not so. Get it by bouncing ultrasounds against the leaves that surround the moth immobilized. Although the bats orejudos not be able to detect the prey in flight front because the sound waves bounce off the sheet and mask any signal from the insect, do not have any difficulty to detect them when they approach the leaves from oblique angles.

This strategy reveals a new step in the arms race between the sensory systems of predators and prey, and it challenges the hypothesis that the silence can be an effective tool for self-defense for the prey of the bats insectivores.

in order To understand the emergence of this evolutionary strategy is to consider the battles fought between bats and nocturnal insects for thousands of generations. Bats love moths: they are big and nutritious and an excellent source of food for some animals that can eat almost their own body weight in insects each night. If you get to catch a moth girl, a bat saves the work done and the energy expended chasing prey smaller and less substantial.

moths counter-attack,

As there’s no shortcut without work, things are not so easy. Given that they are a few pieces very much coveted among the various species of bats, moths have developed a whole battery of strategies to combat the echo. Some species, for example, have scales that “ stuck ” the sonar of bats to avoid detection. Others have developed antennas that can detect ultrasonic echolocation, so they can escape before falling prey to a bat on the prowl.

The bats not have taken such countermeasures evolutionary lightly. In response, some species such as the european bat forest (Barbastella barbastellus) have been developed ultrasonic signals and alternatives, “ echolocation stealth ”, emitted at frequencies and intensities that the moths can’t detect. The echolocation of this species is of a much lower intensity (10 to 100 times lower) than the calls of other bats that hunt in similar environments.

most of The bats are hunters of open space to catch flying insects in any outdoor location such as the clearings of forests. Hunting outdoor prevents a sonar for echolocation collide with the environment. However, the fact that the bat large-eared have devised a solution to this problem suggests that they might arise more surprises in the battle technology of the bats to capture their prey, especially if it is investigated between the vespertiliónidos, a family of bat specialises in hunting moths.

The world beyond our senses

Accustomed to perceive with our five senses, we ignore the fact that the world is full of signals that we don’t perceive. Creatures of tiny, live in a different world governed by the senses that we are strangers because they exceed the scope of our limited perception of the sensations family. We are extraordinarily gullible and we are very predisposed to the acceptance of new powers with which the deceivers of the paranormalidad and magic induce us to believe in a supernatural world.

Surrounded by so many things fascinating and real that we do not see, hear, smell, touch, or taste, we are not aware that nature is more than what we can perceive, that the powers of perception “parahumana” are all around us in birds, bees or bats.

The use of the leaves as mirrors acoustic is the last frontier known in the eternal fight between bats and their prey. As was the case in the wards of the dómine Cabra, hunger sharpens the senses.

Manuel Peinado Lorca is a Professor of University. Department of Life Sciences and Researcher at the Instituto Franklin for north American Studies, University of Alcalá

This article was originally published in The Conversation .

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