Shell, Beak, Tusk: Shared Traits and the Wonders of Adaptation

Gr 1–4—Evolution encourages the development of traits that help animals to eat and avoid being eaten. Convergent evolution is the development of the same traits by different species, often located geographically far apart, in order to survive in their specific environment. On facing pages, animals with beaks, shells, or tusks are paired with others that have exhibited similar adaptations. For example, both the shell of a turtle (a reptile) and that of a snail (a mollusk) protect the more tender parts of the animals' bodies from harm. Black-and-white camouflage helps the penguin escape detection from the orca and allows the orca to sneak up on the penguin. A parrot and an octopus both use beaks to get at their food. High-quality, full-color, close-up photographs illustrate the concepts discussed and spotlight some more unusual animals from a variety of geographic regions. Heos suggests the possibility of discovering many other animals that arose through convergent evolution.