This brings us to the core passerines, Passerida. It is the sister group to the Corvida. The Passerida are concentrated in four main groups: Sylvioidea, Certhioidea, Muscicapoidea, and Passeroidea. The taxonomy of Passerida has been changing rapidly and current checklists lag well behind the latest research. That goes double for the four big passerine groups: Sylvioidea, Certhioidea, Muscicapoidea, and Passeroidea. We know the broad outlines of how they relate, but the placement of many genera (and even which species go in those genera) remains uncertain. Some are likely still not even placed in the correct major group. I will not attempt a detailed listing of the genera in each family. I will say that whatever checklist order you are using, it is some distance from reality.
The Passerida start with one more Australasian group, the Australian robins (Petroicidae). The genetic studies that have been done have been equivocal on its placement—whether it goes before or after the Picathartoidea. Jønsson and Fjeldså, (2006a) argue that placing it first makes the best sense both genetically and biogeographically. Genetically, the rest of the Passerida share an insertion in the nuclear c-myc gene that the Petroicidae lack (Ericson et al., 2000). The biogeographic sense is that all of the Petroicidae are Australasian. It seems unlikely the Passerida would develop in Africa (the Picathartoidea), then suddenly jump back to Australia before returning to Africa.
Jønsson and Fjeldså (2006b) use the “supertree” they developed (2006a) to analyze the timing of split between the Corvida and Passerida. They argue that the rest of the Passerida originated around 45-50 million years ago in a single dispersal from Australia, across the Indian Ocean, to Africa. They also found that various corvid and para-corvid species later dispersed through the islands to southeast Asia, after the Australian plate moved closer to Asia.
Three small groups (rockfowl, rockjumpers, and rail-babblers; kinglets; hyliotas) branch off separately near the base of the Passerida tree. The Picathartoidea (rockfowl and rockjumpers) were considered Incertae sedis by Sibley and Monroe and there has been some discussion about whether they are best considered a corvid relative or part of Passerida. Several recent papers have made the case for placing them here (Barker et al., 2004; Beresford et al., 2005; Cracraft et al., 2004). Of course, once we have placed the Petroicidae in the Passerida, the choice is forced, Picathartoidea must also be in the Passerida. Recent research by Jønsson et al. (2007) found that the rail-babbler belongs in the same clade. Each is distinct enough, and the genetic separation large enough, that we consider each a separate family in the Picathartoidea.
Until recently, the Regulidae (kinglets) were considered one of the Sylvioidea (what Gill refers to as Old World Insect Eaters). The hyliotas were considered part of Sylviidae itself. Current evidence suggests that neither group is particularly closely related to the Sylvioidea and so each is placed in its own superfamily (Reguloidea and Hyliotoidea) as in Jønsson and Fjeldså (2006a). However, their placement here is far from certain. An alternate reading of Fuchs et al. (2006a) would place Hyliota in the Certhioidea-Muscicapoidea clade. The kinglets tend to show up in different places in different studies, but usually in a relatively basal position and often in the Muscicapoidea (e.g., Spicer and Dunipace, 2004; Voelker and Spellman, 2004; Zuccon et al., 2006; Reddy and Cracraft, 2007).
The next division is between the Sylvioidea and the remaining passerines, which break into three groups--Certhioidea, Muscicapoidea, and Passeroidea. This means that Sylvioidea must be listed before Certhioidea and Muscicapoidea, unlike the modified SAM list which has Muscicapoidea first. Don Roberson's 7th edition family list covers many of the changes to the Sylvioidea and Muscicapoidea quite well, but does not treat Certhioidea as a separate group.
Sylvioidea, Certhioidea, and Muscicapoidea
Sylvioidea has been a mess for a long time. Both the Sylviidae and Timaliidae have been treated at taxonomic trashcans. If a species is hard to classify, just dump it in the Sylviidae or Timaliidae. Then we don't have to worry about it. This has been a particular problem because many of the species look very similar. The lack of a distinct juvenile plumage helps separate them from the Muscicapioidea, but there's really not much to go on in terms of morphology.
Just how much of a mess the Sylvioidea were is exemplified by the Sibley-Monroe checklist. They removed the cisticolas, kinglets, parids, and white-eyes and others, and still had a mass of 560 species lumped together in the family Sylviidae with the Timaliidae nested inside as a tribe (Timaliini). This was actually progress as it was an admission about how little we knew.
Although DNA hybridization studies gave more information than using morphology alone, they were not powerful enough to untangle the Sylviidae-Timaliidae. Too many of the birds involved were not only too similar in form, they were too similar in DNA for the blunt tools of DNA hybridization to handle. The task needed sharper tools, the ability to directly compare DNA sequences.
Recently, Sylvioidea has undergone major restructuring, starting with the formation of a new superfamily---Certhioidea (Cracraft et al., 2004). The Certhioidea are comprised of several families of small birds that the modified SAM list has at the beginning of the Sylvioidea. In fact, they are more closely related to the Muscicapoidea! One could include them in the Muscicapoidea, but I follow the Tree of Life and place in a separate superfamily. The families in question are the Sittidae (nuthatches), Tichodromadidae (wallcreeper), Hypocoliidae (hypocolius), Polioptilidae (gnatcatchers and gnatwrens), and Troglodytidae (wrens).
Although these results cleared the ground, what was really needed was to sample a large number of Sylviod taxa. Alström, Beresford, Ericson and others attacked the problem on a wide scale, while Cibois and company focused on Timaliidae. The result is that the Sylvioidea have been sliced and diced. Much work is still to be done on Sylvioid taxonomy, but Alström, Cibois, and their associates have managed to build a framework of Sylvioid families. The framework will probably need some adjustment and rearrangement, but I think it creates a coherent set of families.
The framework involves the creation of ten new families: Panuridae, Stenostridae, Sylviettidae, Nicatoridae, Cettiidae, Phylloscopidae, Acrocephalidae, Donacobiidae, Bernieridae, and Megaluridae. The papers by Alström et al. (2006), Beresford et al. (2005), and Jønsson and Fjeldså (2006a) lay out the big picture.
The Sylvioidea start with a small clade containing three small families: Stenostridae (fairy flycatchers), Remizidae (penduline-tits), and Paridae (chickadees and titmice). This clade is the sister group to the rest of the Sylvioidea. The Stenostridae are one of the new families. They are a group of small African and Asian flycatchers that were previously scattered across three superfamilies. They include the Fairy Flycatcher Stenostira (Sylvioidea: Sylviidae), the Elminia (Covoidea: Monarchidae) crested-flycatchers, and the Culicicapa (Muscicapoidea: Muscicapidae) canary-flycatchers. As mentioned on the previous page, the Paridae gain Hume's Ground-Tit (formerly Hume's Ground-Jay), Pseudopodoces humilis from the Corvidae (James et al., 2003; Gill et al., 2005).
Once again, the Sylvioidea split into two clades. The smaller one contains the Panuridae and Alaudidae (larks). Panuridae currently consists of just one species, the Bearded Reedling (Panurus biarmicus), although others may still be hidden within Sylviodea. There have been many opinions about how to classify the Reedling, and it is sometimes considered a parid or parrotbill, and usually named to match (Bearded Tit or Bearded Parrotbill). It had recently been considered a parrotbill, in the now-defunct Parrotbill family (Paradoxornithidae). The modified SAM list had already rolled the Parrotbills into the Sylviidae. Using overlapping but distinct data sets, Alström et al. (2006), Ericson and Johansson (2003b), and Fuchs et al. (2006) concur that Panurus is sister to the larks.
The larks are the other half of this clade. Although they were considered part of Passeroidea in the modified SAM list, this is not correct. Rather, they belong in the Sylvioidea. Although the placement of the larks may have changed, their composition has not. This reflects the fact that they are one of the two easily identifiable passerine families (the swallows are the other).
The remaining families in the Sylvioidea are either restructured versions of existing families or result from a break-up and rearrangement of the Sylviidae (and other Sylvioid families). Cibois (2003), Cibois et al. (1999,2001,2002), Fuchs et al. (2006a,b), Nguembock et al. (2007), Pasquet et al. (2006), and Zhang et al. (2007) fill in many of the details.
The Sylviettidae are one of the new families. This is formed entirely from the Sylviidae and consists of crombecs and African warblers. This is followed by the nicators (Nicatoridae), another African clade. They were formerly considered to be in the bulbul family, but seem not closely related to anything else. I put them in their own family for now.
We move back to familiar territory with the swallows and long-tailed tits. The long-tailed tits seem to be the sister group of another new family, the Cettid bush-warblers (Cettiidae). This group has an primarily African and Asisan distribution and includes the Hylia and Tit-Hylia, the latter having come from the Remizidae (Sefc et al., 2003). Classification of the Tit-Hylia (Pholidornis rushiae) has long been controversial. It has variously been placed in at least 7 other families: Sylviidae, Estrildidae, Dicaeidae, Nectariniidae, Remizidae, Hyliidae and Meliphagidae.
These are followed by the leaf-warblers (Phylloscopidae), which is a new family consisting of about 70 species in two genera formerly belonging to the Sylviidae.
The bulbul family Pycnonotidae sees only minor changes. It is followed by the cisticolas, which have gained and lost a few genera. Keep in mind that Cisticolidae itself was only recently created from Sylviidae by Sibley and Ahlquist (1990). Next are the reed-warblers, Acrocephalidae, another new family formed out of the Sylviidae. Only Scotocerca inquieta comes from elsewhere (Cisticolidae).
The monotypic Donacobius has various been considered a wren, thrush, or mockingbird. It is none of these. It is a sylvioid of some sort, probably fairly closely related to the following two families. We place it next in its own family.
After the Donacobius is the new Malagasy warbler family, Bernieridae. It too mostly comes from the Sylviidae, except for Bernieria itself, which comes from the Pycnonotidae (Cibois et al., 1999, 2001). Another new family follows, the Megalurid warblers and grassbirds, As with several of the other new families, the Megaluridae are comprised entirely of former Sylviidae.
The tree diagram in Cibois (2003) could be consistent with 1, 2, or 3 more families (this is hidden on the diagram because only one of the Zosteropidae is included). I choose option 3. Many of the remaining Sylviidae are grouped together in the new Timaliidae. However, Sylvia itself, together with a few of the old Sylviidae and the genus Rhopophilus (Cisticolidae), are left to carry on the name Sylviidae. The Yuhinas and at least 3 species of Stachyris, all of which are closely related to Zosterops, are transferred to the Zosteropidae. Neither Stachyris nor Yuhina appear to be monophyletic, so expect some adjustment of these genera.
The new superfamily Certhioidea is treated as sister to the Muscicapoidea. The big change to the Muscicapoidea is the whole branch inherited from Sylvioidea. The Buphagidae (oxpeckers) must be given their own family to avoid merging the Sturnidae and Mimidae. The Philippine creepers (Rhabdornis) have variously been considered a separate family (HM03), a creeper (Sharpe 1903), or a sylvioid (Gill 1995), but they actually are embedded within the Sturnidae (Zuccon et al., 2006; Lovette and Rubenstein, 2007). They are basal members of a clade of south Asian and Pacific Starlings, which includes Hill Myna. The old world chats and wheatears are transferred from Turdidae to Muscicapidae.
The last big piece of the Passeriformes is the Passeroidea which we consider in the final section.
- Australasian Robins (Petroicidae)
- Rockfowl (Picathartidae)
- Rockjumpers (Chaetopidae)
- Rail-babbler (Eupetidae
- Kinglets (Regulidae)
- Hyliotas (Hyliotidae)
- Fairy Flycatcher, Canary-Flycatchers, Crested-Flycatchers (Stenostridae)
- Penduline-Tits (Remizidae)
- Tits, Chickadees (Paridae)
- Bearded Reedling (Panuridae)
- Larks (Alaudidae)
- Crombecs, African Warblers (Sylviettidae)
- Nicators (Nicatoridae)
- Martins, Swallows (Hirundinidae)
- Long-tailed Tits, Bushtit (Aegithalidae)
- Cettid Bush-Warblers, Hylia, Tit-Hylia (Cettiidae)
- Leaf-Warblers (Phylloscopidae)
- Bulbuls, Greenbuls (Pycnonotidae)
- African Warblers (Cisticolidae)
- Reed-Warblers (Acrocephalidae)
- Donacobius (Donacobiidae)
- Malagasy Warblers (Bernieridae)
- Megalurid Warblers, Grassbirds (Megaluridae)
- Sylvia Warblers, Parrotbills, Wrentit, Fulvettas (Sylviidae)
- Babblers, Laughingthrushes (Timaliidae)
- White-eyes (Zosteropidae)
- Nuthatches (Sittidae)
- Wallcreeper (Tichodromadidae)
- Tree-Creepers (Certhiidae)
- Hypocolius (Hypocoliidae)
- Gnatcatchers, Gnatwrens (Polioptilidae)
- Wrens (Troglodytidae)
- Waxwings (Bombycillidae)
- Silky-flycatchers (Ptilogonatidae)
- Palmchat (Dulidae)
- Dippers (Cinclidae)
- Oxpeckers (Buphagidae)
- Mockingbirds, Thrashers (Mimidae)
- Starlings, Mynas (Sturnidae)
- Thrushes (Turdidae)
- Chats, Wheatears, Old World Flycatchers (Muscicapidae)
Modified SAM List (Gill, 1995)
- Rockfowl, Rockjumper (Picathartidae) includes Chaetopidae
- Waxwings, Silky-flycatchers (Bombycillidae) includes Ptilogonatidae
- Palmchat (Dulidae)
- Dippers (Cinclidae)
- Thrushes (Turdidae) includes Alethe, Brachypteryx, Heinrichia, Monticola, Myophonus, and Pseudocossyphus (Muscicapidae); excludes Cochoa and Grandala (Muscicapidae)
- Old World Flycatchers, Chats (Muscicapidae) see Turdidae above; also Culicicapa (Stenostridae)
- Starlings, Mynas (Sturnidae) includes Buphagidae; excludes Rhabdoris (Sylviidae)
- Mimic Thrushes, Thrashers (Mimidae)
Old World Insect Eaters
- Nuthatches, Wallcreeper (Sittidae) includes Tichodromadidae
- Creepers (Certhiidae)
- Wrens (Troglodytidae) includes Donacobiidae
- Gnatcatchers, Verdin (Polioptilidae) includes Auriparus (to Remizidae)
- Chickadees, Titmice (Paridae) excludes Pseudopodoces (from Corvidae)
- Penduline-tits (Remizidae) excludes Pholidornis (from Cettiidae); Auriparus (from Polioptilidae)
- Long-tailed Tits (Aegithalidae) excludes Leptopoecile (from Sylviidae)
- Swallows, Martins (Hirundinidae)
- Kinglets (Regulidae)
- Bulbuls (Pycnonotidae) includes Nicatoridae; also Bernieria (to Bernieridae), Malia, Neolestes (Incertae sedis)
- Hypocolius (Hypocoliidae)
- African Warblers (Cisticolidae) excludes Bathmocercus, Phyllolais, Artisornis, Neomixis, part of Orthotomus (all from Sylviidae); includes Rhopophilus (to Sylviidae), Scotocerca (to Acrocephalidae)
- White-eyes (Zosteropidae) excludes Apalopteron (Meliphagidae), Rhopophilus (Cisticolidae), Yuhina and part of Stachyris (Sylviidae)
- Old World Warblers, Babblers, Wrentit, Laughingthrush (Sylviidae) includes Hyliotidae, Megaluridae, Panuridae, Phylloscopidae, Sylviettidae, Acrocephalidae (except Scotocerca), Cettiidae (except Erythrocercus, Pholidornis), Timaliidae; also Leptopoecile (Aegithalidae); Newtonia (Vangidae), Rhabdornis (Sturnidae), Stenostira (Stenostridae), Bathmocercus, Phyllolais, Artisornis, Neomixis (Cisticolidae), Yuhina (Zosteropidae), and Kakamega (somewhere in Muscicapoidea)