Thursday, February 10, 2011

Ontogeny reconfirms Phylogeny

Ontogeny recapitulates phylogeny is a saying put forth by Ernst Haeckel to describe how the process of development in vertebrate embryos mirrors the evolutionary process that vertebrates have undergone through history (e.g. a human embryo goes through stages where they resemble fish, tadpoles, etc.). While Haeckel's original hypothesis is not what exactly happens, it has been shown that closely related organisms undergo similar developmental processes.

A new study out of the Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University may help resolve a long-standing debate on the development of digits in the hands of birds and dinosaurs.
The debate and the findings of the new study are well-reported in an article from ScienceNOW.

Given the plethora of additional evidence supporting a dinosaur origin for birds, hopefully this is the final nail in the coffin for the argument that birds originated from more basal archosaurians.
Photo: Archaeopteryx manus