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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, […]

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articles biology

Larvae as the epitome of evolution

Read the previous section: What a larva is. Francis M. Balfour set the pace on discussions about the evolutionary importance of larvae by addressing many of the fundamental questions regarding larval evolution (Balfour, 1874; Balfour, 1880; Balfour, 1881). He wondered about the ancestry of larvae. Can larvae reveal the ancestral forms of metazoans? He indicated […]

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articles biology

Turtles, embryos, and fossils

I wrote a text about the development and evolution of the turtle shell on The Node: Turtles in a nutshell. It shows the beginning of shell formation in embryos and how this can help us understand the evolution of such unique body pattern. 3D animations and fossils are included! Never thought I would post a […]

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notes biology

This is NOT your family tree