Answer:
morphological
Step-by-step explanation:
The morphological concept is the process of identifying a species by its physical characteristics and features.
Field guides use this concept to help people identify different species by comparing the features of an organism to the images and descriptions listed in the guide.
This method of identification is based on the individual characteristics of the species, such as size, shape, color, and other traits that can help to distinguish it from similar species.
By studying these features, individuals can accurately identify a species and learn more about its biology.