Homology and parallelism in arthropod sensory processing

Prominent eyes and antennae serving vision and olfaction are distinctive features of many arthropods, while underlying ganglia such as insect optic lobes, antennal lobes and mushroom bodies (Figure 25.1) occupy much of the nervous system. Well-developed sensory systems serving motor coordination, navigation and memory are characteristic of mobile animals, and so understanding their evolution promises insights into the emergence of arthropods from simpler ancestors.