Recently, the large Parus group has been gradually split into several genera (as indicated below), initially by North American ornithological authorities and later elsewhere.
Whereas in the mid-1990s, only Pseudopodoces, Baeolophus, Melanochlora, and Sylviparus were considered well-supported by the available data as distinct from Parus.
Today, this arrangement is considered paraphyletic as indicated by mtDNA cytochrome b sequence analysis, and Parus is best restricted to the Parus major—Parus fasciiventer clade, and even the latter species' closest relatives might be considered a distinct genus.

In the Sibley-Ahlquist taxonomy, the family Paridae is much enlarged to include related groups such as the penduline tits and long-tailed tits, but while the former are quite close to the tits and could conceivably be included in that family together with the stenostirid "warblers", the long-tailed tits are not.
Indeed, the yellow-browed tit and the sultan tit are possibly more distant to the tits than the penduline tits are.
If the two current families are lumped into the Paridae, the tits would be a subfamily Parinae.

Alternatively, all tits—save the two monotypic genera discussed in the preceding section and possibly Cyanistes, but including Hume's ground tit—could be lumped in Parus.
In any case, four major clades of "typical" tits can be recognized: the dark-capped chickadees and their relatives (Poecile including Sittiparus), the long-crested Baeolophus and Lophophanes species, the usually tufted, white-cheeked Periparus (including Pardaliparus) with more subdued coloration and finally Parus sensu stricto (including Melaniparus and Machlolophus).
Still, the interrelationship of these, as well as the relationships of many species within the clades, are not well-resolved at all; analysis of morphology and biogeography probably gives a more  robust picture than the available molecular data.

Tits have settled North America twice, probably at some time during the Early-Mid Pliocene.
The first were the ancestors of Baeolophus, with chickadees arriving somewhat later.
Recently, the large Parus group has been gradually split into several genera (as indicated below), initially by North American ornithological authorities and later elsewhere. Whereas in the mid-1990s, only Pseudopodoces, Baeolophus, Melanochlora, and Sylviparus were considered well-supported by the available data as distinct from Parus. Today, this arrangement is considered paraphyletic as indicated by mtDNA cytochrome b sequence analysis, and Parus is best restricted to the Parus major—Parus fasciiventer clade, and even the latter species' closest relatives might be considered a distinct genus.
In the Sibley-Ahlquist taxonomy, the family Paridae is much enlarged to include related groups such as the penduline tits and long-tailed tits, but while the former are quite close to the tits and could conceivably be included in that family together with the stenostirid "warblers", the long-tailed tits are not. Indeed, the yellow-browed tit and the sultan tit are possibly more distant to the tits than the penduline tits are. If the two current families are lumped into the Paridae, the tits would be a subfamily Parinae.
Alternatively, all tits—save the two monotypic genera discussed in the preceding section and possibly Cyanistes, but including Hume's ground tit—could be lumped in Parus. In any case, four major clades of "typical" tits can be recognized: the dark-capped chickadees and their relatives (Poecile including Sittiparus), the long-crested Baeolophus and Lophophanes species, the usually tufted, white-cheeked Periparus (including Pardaliparus) with more subdued coloration and finally Parus sensu stricto (including Melaniparus and Machlolophus). Still, the interrelationship of these, as well as the relationships of many species within the clades, are not well-resolved at all; analysis of morphology and biogeography probably gives a more  robust picture than the available molecular data.
Tits have settled North America twice, probably at some time during the Early-Mid Pliocene. The first were the ancestors of Baeolophus, with chickadees arriving somewhat later.
Tit (bird)