DragonflyIssuesInEvolution13 Wiki
Embryo comparison

Presence of gill slits in chicken and human embryos during development indicate common ancestry with fish.

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Ontogeny is an organism's development from an embryo to an adult. It is also known as ontogenesis. The study of an organism's ontogeny can be used to understand its evolutionary history because this history is often present in development. It may show evidence of divergence where a common developmental characteristic is present in two different species.

Podos, J., Huber, S.K., & Taft, B. (2004). Bird song: The interface of evolution and mechanism. Annual Review of Ecology, Evolution, and Systematics, 35, 55-87.



Ontogeny example[]

An example of ontogeny is the embryonic stage in humans in which gill slits are present, suggesting fish ancestry.