Ornithurae

Definition

Ornithurae is a clade that includes all living birds (Neornithes) and their closest extinct relatives. It is characterized by features such as a more modern avian skeletal structure and advanced flight adaptations.

5 Must Know Facts For Your Next Test

1. Ornithurae encompasses all extant bird species along with their closest extinct relatives.
2. Members of Ornithurae exhibit key skeletal adaptations like a fused pelvis and pygostyle.
3. This clade emerged during the Early Cretaceous period, approximately 130 million years ago.
4. Ornithurae is distinct from Enantiornithes, another group of prehistoric birds that went extinct at the end of the Cretaceous period.
5. Modern birds' advanced flight capabilities are largely due to evolutionary developments within Ornithurae.

Review Questions

• What time period does the clade Ornithurae date back to?
• What distinguishes Ornithurae from Enantiornithes?
• Which structural adaptations are characteristic of Ornithurae?

Related terms

Neornithes:

Modern birds classified under this group include all current avian species.

Enantiornithes: An extinct group of prehistoric birds that lived alongside early members of Ornithurae.

Pygostyle: The fused terminal vertebrae in the tail of birds, providing support for tail feathers.