Ekolokation

Ekolokation, often called echolocation in English, is a biological sonar system used by certain animals to determine the location, distance, size, and texture of objects around them by emitting sounds and listening for their echoes. The best-known users are bats and toothed whales (such as dolphins and sperm whales), but a few terrestrial species, including some shrews and tenrecs, also employ echolocation.

The mechanism involves producing acoustic signals and interpreting returning echoes. Emitted sounds are typically ultrasonic in bats and in many whale species, and are produced by specialized vocal or nasal structures. The animal’s auditory system analyzes the time delay between emission and echo to gauge distance, uses interaural differences to infer direction, and examines spectral changes in the echoes to infer object properties like texture and size. Some animals can also detect Doppler shifts to estimate relative motion.

In bats, echolocation is highly adaptive: callers may switch between searching and hunting modes, adjusting frequency, duration, and call rate as they narrow in on prey. In toothed whales, echolocation involves powerful clicks focused by the skull and surrounding tissues, helping them detect prey and navigate murky or dark aquatic environments.

Echolocation has evolved independently in several lineages and plays a crucial role in nocturnal foraging and navigation for bats, as well as in complex marine foraging strategies among toothed whales. It has inspired human technology, notably sonar systems and biomimetic sensors, and remains a key area of study in neuroethology and sensory ecology.