Microbats paint the night with larynx-made ultrasound
Most microbats fire calls from fourteen thousand to over one hundred thousand hertz—far above human hearing—and read the returning echoes. Laryngeal ultrasound, beamed through nose or mouth, builds a sound-picture of insects, wires, and cave walls. The tragus in each ear helps parse that sonic world.
Traditionally, bats split into large Megachiroptera and smaller Microchiroptera that echolocate. Microbats measure about four to sixteen centimetres long. Most eat insects; larger species take birds, lizards, frogs, smaller bats, or fish. Only three species—the vampire bats of South and Central America—feed on blood of large mammals or birds. Leaf-nosed forms may prefer fruit and nectar or, like Vampyrum spectrum, vertebrate prey; horseshoe bats use elaborate noseleaves for insect hunts. Compared with megabats, microbats lack a claw on the second finger, usually have smaller eyes, larger ears with a tragus, and more varied teeth matching insect, flesh, fruit, nectar, or blood diets.
Echolocation compares emitted wavelengths with reflections. Elastic vocal folds turn lung airflow into acoustic waves; the larynx sits at the top of the trachea amid cricothyroid muscles. Laryngeally echolocating microbats show a telling anatomy: the stylohyal bone articulates with the tympanic bone, often flattened at the cranial end, linking throat to middle ear so the brain can register outgoing and incoming pulses. Other bats may click tongues or wings instead. Egyptian fruit bats echolocate differently from typical microbat laryngeal calls. Gene CPLX1 has been tied to ultrasonic production.
Molecular work showed classic microbats are paraphyletic: rhinolophoid "microbats" sit closer to megabats. Modern orders therefore use Yangochiroptera and Yinpterochiroptera rather than a clean mega/micro split. Families once lumped as microbats range from emballonurids and vesper bats to bulldog bats and ghost-faced mormoopids. Whatever the cladogram, the everyday marvel remains: a mammal that speaks in ultrasound and hears its own future in the echo.
Source: Microbat
