In this activity, Namib and Antarctic arthropods are used to illustrate several important biological principles. Among these are the key ideas that form follows function and that the environment drives evolution. In addition, students will discover that the climates of the Namib Desert and the Antarctic Peninsula are similar in several ways, and that these arthropods have evolved some analogous adaptations. This investigation is a good introduction to the phylum Arthropoda, the most successful group of animals on Earth, and spotlights the group's ability to occupy some of the most challenging niches on the planet (National Science Content C--Life Science; NRC 1996).