Morphology

(noun. /mor-FAW-luh-jee/) 

by Zoe Terwilliger

What does it mean? 

Morphology is the study of physical forms and features of organisms. “Morphological characteristics” often refer to features that describe the way the organism looks and structural aspects of that organism. 

Morphology can be characterized in two different ways – external and internal. External morphology describes things that can be seen on the outside of the organism. External morphology can describe things like fur, leaf shape, flower colour, leg/fin shape and size. Internal morphology refers to anatomical structures of the organism. Internal morphology could describe things like presence/absence of organs, shape/size of organs, etc. 

Organisms used to be classified by morphology all the time. In fact, many organisms were often thought to be ancestrally related simply because of a shared morphological trait. However, with the advancement of molecular biology, we are able to better identify closely related species or sister species. 

Figure 1: Morphological characteristics of the American crocodile include an elongated snout and jaw. They also have four short, stocky legs and strong jaws. Other morphological characteristics of the species include their sharp teeth, scaled bodies, and nictitating membranes that protect their eyes when submerged in water.

How do I use it in a sentence?

The morphological characteristics of a crocodile include its scaly body, long tail, extended snout and mouth, and webbed toes.

A morphological characteristic of a human is a sternocleidomastoid muscle.

The humpback whale was named for a morphological characteristic unique to it – its fin!

Related terms

Morphospecies Concept

Phylogenetic Species Concept

Biological Species Concept

Fields of Study in which this term is commonly used

Anatomy
Evolution
Ecology
Botany