|morphology (môr-fŏl'ə-jē) Pronunciation Key
The size, shape, and structure of an organism or one of its parts. Biologists usually describe the morphology of an organism separately from its physiology. In traditional systems of taxonomy, classifications were based on the morphological characteristics of organisms. However, a method of classification based purely on morphology runs the risk of grouping together organisms that are actually relatively unrelated but have evolved similar features. In more modern systems of taxonomy, the genetic similarity of organisms, studied through the methods of molecular biology, is considered in addition to morphology when establishing taxa.