For XPBeta, maybe this will help you understand:
titmouse, common name for members of the Paridae, a family of passerine birds, which includes the tits, titmice, and chickadees. They are small, active birds with short, pointed bills and strong legs. Their soft, thick plumage is colored in grays and browns, occasionally highlighted by black and white or blue and yellow. Titmice are found chiefly in the Northern Hemisphere and also in Asia and Africa. They are adaptable and can be taught to perform tricks. In the wild, titmice travel in mixed flocks with nuthatches, creepers, kinglets, and woodpeckers, feeding mostly on small insects but also on seeds, fruits, and berries. Typical of the family are the blackcapped chickadee, Parus atricapillus, of the NE United States, the nearly identical Carolina chickadee of the South, and the similar willow tit of Europe and the British Isles. Some titmice have crests, e.g., the crested tit of Eurasia and the tufted titmouse, Lophophanes bicolor, a mouse-gray bird with rust side patches common in the E United States. These typical titmice nest in tree cavities; the long-tailed tits weave complex bag nests. To this group belongs the Javanese pygmy tit (3 in./7.5 cm long, most of it tail); the bush tits of the American West are closely related. A third group, the penduline tits, are named for their hanging bag nests; the only American species is the western verdin. Titmice are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Passeriformes, family Paridae.