Homologous Structures

Homologous structures are parts of the body that are similar to those of other organisms and are used for a similar purpose. This is the leg of a dog, which is used for propulsion when walking or running as well as for balance. This is similar to the leg of a cat, tiger, or wolf. This similarity in structure and in purpose most likely means that these animals are related in some way. Unlike analogous structures, which evolved differently but are used similarly, homologous structures evolved and are used similarly. This is an example of divergent evolution.