A somite's a division of the body of an animal. In vertebrates this's mainly discernible in the embryo stage, in arthropods it's a characteristic of a hypothetical ancestor. In vertebrates In the developing vertebrate embryo, somites (or primitive segments in older texts) are masses of mesoderm distributed along the two sides of the neural tube and that'll eventually become dermis (dermatome), skeletal muscle (myotome), and vertebrae (sclerotome). Because the sclerotome differentiates before t… (More on Somite)