Thecarinates

Thecarinates is a term used to describe a clade of birds that includes the passerines (songbirds and their allies) and a few other groups, such as the parrots and falcons. This classification is based on anatomical and genetic evidence that suggests a shared evolutionary history. The name "Thecarinates" refers to the presence of a keel-like structure on the sternum, which provides an anchor for flight muscles.

Historically, avian classification has undergone significant revision as new data emerged. Thecarinates represent a modern interpretation of bird relationships, moving away from older systems that relied solely on gross morphology. Genetic studies, in particular, have been instrumental in solidifying the relationships within this group. While the exact composition and precise branching order within Thecarinates continue to be refined by ongoing research, the core group remains consistent. The broad inclusion of diverse avian orders highlights the significant evolutionary diversification that has occurred within this lineage.