ratite bird
Học thuậtThân thiện
Definition
Noun: A ratite bird is a member of a diverse group of flightless birds characterized by a flat, raft-like breastbone (sternum) that lacks a keel. The keel is a prominent ridge found in flying birds where powerful flight muscles attach. Ratites are typically large, have strong legs adapted for running, and include species such as ostriches, emus, and kiwis.
Examples of Usage
- The ostrich, the world's largest ratite bird, can run at remarkable speeds.
- Scientists study the evolution of ratite birds to understand how flightlessness developed in different continents.
- Unlike most birds, a ratite bird has a flat breastbone without a keel.
Advanced Usage
- Ratite is often used as a shorthand noun to refer to a ratite bird.
- The museum's exhibit features skeletons of various ratites.
- The term is used in biological and zoological classification (Ratitae or Palaeognathae) to describe this specific infraclass of birds.
Variants and Related Words
- Ratite (noun/adjective): The common abbreviated form.
- Ratite anatomy is distinct from that of carinate (flying) birds.
- Flightless bird (noun phrase): A broader, more general term that includes ratites but also other non-flying birds like penguins, which are not ratites as they have a keeled sternum.
Synonyms
- Flightless bird (in a broad, non-technical sense)
- Palaeognath (in precise taxonomic contexts)
Related Terms & Concepts
- Keel (Carina): The ridge on the breastbone of flying birds, which is absent in ratites.
- Carinate bird: A bird possessing a keeled sternum, capable of flight (the opposite of a ratite).
- Cursorial: Adapted for running, a term often describing ratite locomotion.
Noun
- flightless birds having flat breastbones lacking a keel for attachment of flight muscles: ostriches; cassowaries; emus; moas; rheas; kiwis; elephant birds