For most plants and animals, just listing the family, genus or species is enough to let biologists know what the other levels should be. The most common way to list the taxonomic name of an organism is to list the genus and species; this is known as binomial nomenclature, meaning a two-name system.
The grey jay is a relatively large songbird, though smaller than other jays. A typical adult grey jay is between 25 to 33 cm (9.8 to 13.0 in) long. Its wingspan is around 45 cm (18 in). It weighs about 65 to 70 g (2.3 to 2.5 oz). Adults have medium grey back feathers with a lighter grey underside.
The blue jay is a passerine bird in the family Corvidae, native to North America. It is resident through most of eastern and central United States, although western populations may be migratory. Resident populations are also found in Newfoundland, Canada, while breeding populations can be found in southern Canada. It breeds in both deciduous and coniferous forests, and is common near and in residential areas. It is predominantly blue with a white chest and underparts, and a blue crest. It has a