English: Toxostoma rufum rufum (Linnaeus, 1758) - brown thrashers in Ohio, USA. (April 2016) (photo by Mary Ellen St. John)

Birds are small to large, warm-blooded, egg-laying, feathered, bipedal vertebrates capable of powered flight (although some are secondarily flightless). Many scientists characterize birds as dinosaurs, but this is consequence of the physical structure of evolutionary diagrams. Birds aren’t dinosaurs. They’re birds. The logic & rationale that some use to justify statements such as “birds are dinosaurs” is the same logic & rationale that results in saying “vertebrates are echinoderms”. Well, no one says the latter. No one should say the former, either.

However, birds are evolutionarily derived from theropod dinosaurs. Birds first appeared in the Triassic or Jurassic, depending on which avian paleontologist you ask. They inhabit a wide variety of terrestrial and surface marine environments, and exhibit considerable variation in behaviors and diets.

The brown thrashers shown above may be a bonded pair. The bird in the back may be a male and the front bird may be a female - males are very slightly larger than females (less than half a centimeter size difference in wing length and tail length).

Classification: Animalia, Chordata, Vertebrata, Aves, Passeriformes, Mimidae

Locality: Newark, Ohio, USA

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Species-specific info. provided by Nelson Moore.

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See additional info. at:

en.wikipedia.org/wiki/Brown_thrasher