Answer to Question #273212 in Zoology for Lit

Question

Evolution is often portrayed as producing greater complexity and increased size. Can you think of an example where evolution resulted in reduced complexity or smaller size?

Answer 1

This increase in complexity occurs not because of selection but despite it. Once the genome is more complex, however, further mutations can make a creature's body or behaviour more complex. For instance, having two separate genes means each can be switched on or off at different time or in different tissues.