定義： A life cycle stage of holometabolous insects in which the organism is a pupa and starts with the larval-pupal apolysis and ends with pupal-adult apolysis
定義： the method used by some animals (e.g. bats, dolphins and some whales) to determine the location of something by measuring the time it takes for an echo to return from it. These animals emit sound waves and listen for the echo, calculating the distance to the object from the time lapse between sound emission and the echo returning.
