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biology articles

Segmentation, a question of boundaries

Read the previous section: Spiral cleavage, an oblique matter. Annelids, arthropods and vertebrates show a remarkable morphological diversity (Chipman, 2010). Beneath this multiplicity of shapes and forms lies a common pattern of body organization—a trunk divided into repeated parts. This pattern and the developmental process that generates it are known as segmentation (Minelli and Fusco, […]

Categories
biology articles

Spiral cleavage, an oblique matter

Read the previous section: Larvae as the epitome of evolution. By the end of the 19th century, a series of biologists had dedicated themselves to following and discovering the fate of individual cells of an embryo during ontogeny. These works, known as cell lineage studies1, were critical to disambiguate the relationship between ontogeny and phylogeny, […]