Module 4 Intro

Module 4—Mechanisms of Population Change

Big Picture

© Christian Darkin/Dreamstime

Have you ever heard of or seen one of the “Planet of the Apes” movies? In these shows, apes had evolved into intelligent and advanced beings that took over the planet from humans. The premise was that they continued to evolve and humans did not.

Take some time to look at the illustration above. What thoughts come to mind when you look at it? Did the word evolution pop into your head? Have you ever considered the idea that humans are related to rodents? What kind of proof exists for the illustration above to be true? Is evolution still occurring or is it finished, as the illustration seems to indicate? As you look at the illustration, you may ask yourself how the blob became the sea creature that became the human.

In this module you will learn how a population of “blobs” evolved into a population of sea creatures as a stage toward another movement of evolution. You will have to think in terms of enormous amounts of time and many, many generations of organisms. Some of the ideas about genetic variety and the inheritance of characteristics will be familiar to you from Grade 9 Science.

You will explore the following essential questions in this module:

• How do mutations create species variability?
• Why is sexual reproduction important to the process of evolution?
• How do theories explaining evolutionary change compare?
• What theories attempt to explain the pace of evolutionary change?
• What proof is there that present-day species evolved from ancestral forms?
• What conditions are necessary for speciation?