Simplify the following text for a Grade 10 native English-speaking person.
Original: Avialae ( `` bird wings '' ) is a clade of dinosaurs containing their only living representatives , birds ( Aves ) , and the most immediate extinct relatives of birds .
Simplified: Avialae is a term for birds and their immediate extinct ancestors . It is a clade of dinosaurs containing their only living representatives , birds , and whatever coelurosaurs are regarded as their ancestors .