Modifiers matching ratite:

• modern,
• flightless,
• large,
• extinct,

Simple categories matching extinct:

• animal,
• mammal,
• plant,
• ratite,
• predator,
• herbivore,
• reptile,
• dinosaur,
• organism,
• creature,
• fauna,
• archosaur,
• relative,
• beast,
• equid,
• giant,
• amniote,
• bird,
• human,
• vertebrate,