evodevo

Evo-devo, short for evolutionary developmental biology, is a field that studies how developmental processes shape evolutionary change and how evolutionary history constrains the growth and form of organisms. It seeks to understand how genetic and developmental mechanisms generate the diversity of life and how changes in development open or close evolutionary possibilities.

A central focus is gene regulation and gene regulatory networks, including homeotic (Hox) genes and cis-regulatory elements, which can rewire body plans without altering many proteins. Concepts such as modularity, pleiotropy, heterochrony, and deep homology explain how conserved developmental programs produce a wide array of forms through changes in when, where, and how genes are used.

Historically, evo-devo grew from embryology and classical genetics and gained momentum with the discovery of segmentation genes in the fruit fly Drosophila by Christiane Nüsslein-Volhard and Eric Wieschaus, who shared the 1995 Nobel Prize. Since then, researchers such as Sean Carroll and others have explored how regulatory changes drive evolution and how conserved developmental circuits underlie diverse anatomies.

Methods include comparative gene-expression analyses, functional assays in model organisms, and modern genome editing, including CRISPR, to test developmental hypotheses. Evo-devo integrates genetics, embryology, paleontology, and genomics to link development to macroevolution.

Applications span the evolution of limbs, skulls, and other organs, as well as broader questions about the origins of morphological novelty and the mechanisms that enable evolutionary change across lineages.