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.
Adult Gray whales reach a maximum length and weight of about 48 feet (14 m) and 80, 000 lbs (about 40 tons), respectively. Gray whale calves are, at most, 16 feet long (5 m) when they are born and can weigh up to 1,500 lbs (three-quarters of a ton). Gray whales are baleen whales. Baleen are long flat plates, made of fingernail-like material called keratin, that hang from a whaleâs mouth in place of teeth.