What Type of Symmetry Do Arthropods Have?

Arthropods have bilateral symmetry. When divided into two equal sections, both sides of the arthropod body are mirror images of each other.

Bilateral symmetry is a feature shared by all arthropods. This symmetry refers to how the body is structured, and it is also an indicator of how it forms during gestation. Since arthropods make up 90 percent of the animal kingdom, there are plenty of examples showing this body type, as stated by the Center for Insect Science Education Outreach at the University of Arizona. Some classes found in the phylum Arthropoda include insects, arachnids, crustaceans, chilopods and diplopods. Other characteristics that all arthropods share include an exoskeleton, body segmentation and jointed appendages.

When an animal has bilateral symmetry, its body can be sliced in half along the sagittal plane and each half would be a mirror image. The sagittal plane is an imaginary vertical plane that runs from the front to the back of center of the body. Many different species, up to 99 percent, have bilateral symmetry and not all of them are arthropods. For instance, humans are mammals that have bilateral symmetry.

The other types of body symmetry that appear in nature are radial symmetry, biradial symmetry, spherical symmetry and asymmetry.