1. Paleornithology is a branch of paleontology that focuses on studying the ancient ancestors of modern birds.
古鸟类学是古生物学的一个分支，专注于研究现代鸟类的古老祖先。

2. The paleornithology department at the museum has an extensive collection of fossilized bird remains.
博物馆的古鸟类学部门有着丰富的鸟类化石收藏。