If you've ever seen a bat fly at night, you've no doubt seen how agile they are in flight. It's really quite amazing to remember that a bat's eyes are small and poorly developed making them virtually sightless. But bats see through their ears not their eyes. They use echolocation, a variety of ultrasonic ranging, to locate their prey and to locate objects around them. Dolphins and whales use echolocation as well to help identify their surroundings and also to communicate.

What makes echolocation work is something called ultrasound. Ultrasound is a sound pressure that is inaudible to the human ear because it has a frequency greater than what the human ear is able to distinguish. Although animals like bats, dolphins, and whales have been using it for thousands of years, humans have just begun to harness it over the past several decades. Ultrasound is typically used to reflect sound off of a medium. The reflection signature can then be used to create an image of that medium.

Ultrasound is used in hundreds of different applications and fields. The most common use and familiar of ultrasound is in medical sonography, which is used to create an image of an unborn fetus inside its mother's womb during prenatal care. One of the reasons ultrasound imaging is used so heavily in this application is because it is safe. There are no known dangerous side effects to ultrasonic imaging. By using this process doctor's can gain a wealth of useful information about the unborn fetus, including the gestational age, the location of the fetus, any abnormalities, the number of fetuses, movement, heartbeat, as well as the sex of the child.

But ultrasound has more applications in medicine than just fetal imaging. Soft tissue imaging can also be accomplished through this technology. Ultrasonic scans can be used to image the heart, liver, gall bladder, muscles, ligaments, tendons, and many other parts of the body. Even kidney stones and gallstones can be broken up with high-energy ultrasound pulses, breaking them into smaller sizes that can be safely passed through the body.

Liposuction can also be assisted through ultrasound. Ultra-sound assisted liposuction uses a special tool that transmits ultrasound through the body causing fat cell walls to burst and emulsify, which assists doctors in removal of the fat.

By using this amazing technology that exists naturally in nature, we have been able to create one of the most useful devices of the modern age.