A dichotomous key is an important scientific tool, used to identify different organisms, based the organism's observable traits. Dichotomous keys consist of a series of statements with two choices in each step that will lead users to the correct identification.

How do we use a dichotomous key?

Dichotomous keys are used to identify a variety of things including insects, plants, animals and rocks. A key gives pairs of “either-or” choices that direct the user to the next pair of choices (also known as a couplet) or to the point of identification.

How is a dichotomous key used to identify organisms?

“Dichotomous” means divided into two parts, hence the dichotomous keys always present two choices based on the key characteristics of the organism in each step. By correctly selecting the right choice at each stage, the user will be able to identify the name of the organism at the end.