"Evolution" can be considered a noun or a verb, depending on its use in a sentence.

Noun:

* Definition: The process of gradual change in the characteristics of a species over time.

* Example: "The theory of evolution explains the diversity of life on Earth."

Verb:

* Definition: To develop or change gradually over time.

* Example: "The company is constantly evolving to meet the needs of its customers."

So, to determine the correct part of speech for "evolution," you need to consider the context of the sentence.