ADVERTISEMENT
  About the SA Blog Network













Tetrapod Zoology

Tetrapod Zoology


Amphibians, reptiles, birds and mammals - living and extinct
Tetrapod Zoology Home

Chiffchaffs: a view of passerines from the peripheries (part I)

The views expressed are those of the author and are not necessarily those of Scientific American.


Email   PrintPrint



Substantially simplified depiction of passeridan passerine phylogeny, based mostly on Johansson et al. (2008). All images by Darren Naish except the stenostirid (by Tom Tarrant, licensed under Creative Commons Attribution-Share Alike 3.0 Unported license).

Every now and again I make an effort to get through a little bit more of passerine bird diversity (see the list of articles below for previous efforts). This is such an enormous and vastly diverse clade, alas, that I’ll probably never manage it – unless, that is, that I blog about passerines and not much else for a year or so. What I’ve decided to do here is compile various of the photos I’ve recently taken of assorted passerine species and use them as an excuse to talk about passerine diversity and phylogeny [UPDATE: as you'll see, the article ended up becoming a bit more restrictive in scope...]. It’s a bit like trying to walk across a river in flood – you plant your staff in the riverbed and that section of riverbed, and that section alone, is the bit you get to write about. Whether that analogy makes any sort of sense or not, off we go…

Reading about passerines, are you? Well, here's just a few books to get you started. Photo by Darren Naish.

Oh, what I am getting at with the “view from the peripheries” thing referred to in the title? This is a reference to my pet idea that western Europe – and the British Isles in particular (my home base) – are very much a far-flung, peripheral region when it comes to the evolution and history of groups like the passerines. Think about it: phylogeny shows us that most of the key divergences in passerines happened in Australasia, tropical Asia and Africa (e.g., Beresford et al. 2005, Fuchs et al. 2006). Europe – strongly affected by a recent history of glaciations – has only been colonised by far-flying migrants or by reasonably hardy, cool-climate specialists that moved here after originating further to the south or east. So, in a biogeographical and evolutionary sense, I write to you ‘from the fringes’; from a far-flung, Atlantic outpost that should be considered last whenever we discuss evolutionary history, not first as it typically is due to historical, anthropocentric bias.

Chiffchaff, leaf warbler examplar. Photo by Darren Naish.

This is a Common chiffchaff Phylloscopus collybita, a familiar, ubiquitous leaf warbler here in western Europe. I photographed this particular bird in Carmarthenshire, Wales, and you wouldn’t believe the time and effort it took to get the image you see here (or, if you photograph birds yourself, maybe you would). Leaf warblers (the Phylloscopus species) are slim-billed insectivores, greenish-greyish above and whitish below. There have been occasional efforts to recognise new genera or ‘subgenera’ within Phylloscopus (namely Cryptigata, Seicercus and Acanthopneuste), the result being radical non-monophyly and more confusion than ever (Olsson et al. 2005).

That Common chiffchaff again, co-operatively posing in profile. Photo by Darren Naish.

Where do leaf warblers and kin belong in passerine phylogeny? They’re uncontroversially part of Sylvioidea, the major passeridan passerine clade that includes all Old World warblers as well as bulbuls, cisticolas, white-eyes, Old World babblers and numerous similar birds (Passerida = the clade that contains all sparrow-like, finch-like and warbler-like passerines). However, the idea that all Old World warblers should be classified together is not supported by molecular data. Convention would have it that leaf warblers belong to Sylviidae – the ‘Old World warbler family’ – but the fact that recent phylogenies find Sylvia warblers to be closer to Old World babblers, white-eyes, cisticolids and so on means that this is very wrong, since leaf warblers and kin are clearly not part of this clade (Beresford et al. 2005, Alström et al. 2006, Johansson et al. 2008). The best way to classify leaf warblers may, actually, be to give them their own ‘family’ – Phylloscopidae – that’s close to (but distinct from) Cettidae and related sylvioid clades (Alström et al. 2006, Johansson et al. 2008).

These Old World warbler taxa are always placed together in field guides. But - shock horror - they actually represent three phylogenetically distinct radiations, well separated by tropical taxa. Clockwise from top left: Hippolais (this is H. icterina; image by Vogelartinfo), Acrocephalus (this is A. palustris; image by Dirk-Jan Kraan), Phylloscopus (this is Ph. collybita; image by Andreas Trepte), and Locustella (this is L. fluviatilis; image by Lasse Olsson). Images licensed under Creative Commons Attribution-Share Alike 3.0 Unported license and 2.5 Generic license).

As surprising and radical as it might seem, other Old World warblers conventionally discussed alongside leaf warblers – namely, the Locustella, Acrocephalus and Hippolais warblers – aren’t part of the same group as Phylloscopidae, Cettidae and so on, but are instead part of that bulbul-babbler-cisticola clade (Alström et al. 2006, Johansson et al. 2008). Remember this when you open your field guide and see all those warbler-type birds arranged together on the same few pages: they actually belong to at least three distinct evolutionary radiations, are well separated in the sylvioid tree (except for Acrocephalus and Hippolias, which really are close relatives), and are surrounded in the phylogeny by tropical African and Asian taxa. [Adjacent photos by Vogelartinfo, Dirk-Jan Kraan, Andreas Trepte and Lasse Olsson.]

Chiffchaffs are famously similar to Willow warblers Ph. trochilus in appearance (but not in voice: the name ‘chiffchaff’ is semi-onomatopoeic). Some studies indicate that both are essentially sister-taxa, only the Plain leaf warbler Ph. neglectus of central Asia being ‘intermediate’ between the two (it seems to be closer to chiffchaffs than to the Willow warbler) (Badyaev & Leaf 1997, Helbig et al. 1996, Olsson et al. 2005). Of course, this picture becomes more complex if various of the traditional chiffchaff ‘subspecies’ are recognised as worthy of species rank, like the Iberian chiffchaff Ph. brehmii, Canary Islands chiffchaff Ph. canariensis, Eastern or Mountain chiffchaff Ph. sindianus and Siberian chiffchaff Ph. tristis. Yes, as is so often the case, ‘the Chiffchaff’ is a polytypic entity that encompasses substantial diversity, with some of its ‘subspecies’ being ‘more distinct’ than many universally recognised ‘species’ in other bird groups, and easily differentiable based on morphology, acoustics, hybridisation patterns and DNA (Helbig et al. 1996). [Chiffchaff below by Andreas Trepte; Willow warbler by Rob Bendall/Highfields.]

Common chiffchaff (at left) compared with Willow warbler: note darker legs in chiffchaff. The other differences are less easy to appreciate due to the very different lighting conditions of these images... birds often don't look exactly as they do in books. Chiffchaff image by Andreas Trepte (licensed under Creative Commons Attribution-Share Alike 2.5 Generic license); Willow warbler by (c) Rob Bendall/Highfields.

Regardless, Common chiffchaff and Willow warblers are known to hybridise in places (the hybrids have a ‘hybrid song’, featuring song phrases of both parent species) (da Prato 1993). Despite the stereotype about them being similar except for voice, they’re actually not that difficult to distinguish if you know what to look for: Willow warblers are larger with a shallower, less domed head, slightly longer primary projection, and they’re ‘brighter’, with light brownish/pinkish legs (as opposed to darker grey legs) and have a more washed-out look overall. The habitat preferences of the two are also slightly different. Chiffchaffs are generally restricted to areas where there are tall deciduous trees whereas Willow warblers are more associated with woodland edges, scrubland and clearings. However, the two must be pretty similar in ecological terms since some studies indicate that, when one of the two species occupies a habitat, the other one is discouraged from doing so (Saether 1983). Willow warblers are somewhat larger so tend to have the advantage if they occupy a habitat first (Saether 1983).

A few representative passerines (most of which are rather more exotic than the leaf warblers focused on in this article). Image by Darren Naish.

This article was written as a quick summary, the original plan being that I was going to use it to showcase some of my Welsh chiffchaff photos. It goes without saying that a huge amount of research has been done on leaf warbler hybridisation, distribution, ecology, foraging behaviour, systematics and phylogeny, and you can all help to make this article (and its comments) fantastically complete by saying smart and brilliant things in the comments below. So, over to you… (whackaloons and creationists: let’s see if you can find things to say when Mesozoic dinosaurs and primates aren’t involved).

More Old World passerines as seen “from the peripheries” later. Next: TITS (again). For previous Tet Zoo articles on passerines, see…

Refs – -

Alström, P., Ericson, P. G. P., Olsson, U. & Sundberg, P. 2006. Phylogeny and classification of the avian superfamily Sylvioidea. Molecular Phylogenetics and Evolution 38, 381-397.

Badyaev, A. V. & Leaf, E. S. 1997. Habitat associations of song characteristics in Phylloscopus and Hippolais warblers. The Auk 114, 40-46.

Beresford, P., Barker, F. K., Ryan, P. G. & Crowe, T. M. 2005. African endemics span the tree of songbirds (Passeri): molecular systematics of several evolutionary ‘enigmas’. Proceedings of the Royal Society of London B 272, 849-858.

da Prato, S. R. D. 1993. Chiffchaff. In Gibbons, D. W., Reid, J. B. & Chapman, R. A. (eds) The New Atlas of Breeding Birds. T & A D Poyser, London, pp. 348-349.

Fuchs, J., Fjeldså, J., Bowie, R. C. K., Voelker, G. & Pasquet, E. 2006. The African warbler genus Hyliota as a lost lineage in the oscine songbird tree: molecular support for an African origin of the Passerida. Molecular Phylogenetics and Evolution 39, 186-197.

Helbig, A. J., Martens, J., Henning, F., Schottler, B., Siebold, I & Wink, M. 1996. Phylogeny and species limits in the Palaeoarctic Chiffchaff Phylloscopus collybita complex: mitochondrial genetic differentiation and bioacoustic evidence. Ibis 138, 650-666.

Johansson, U. S., Fjeldså, J. & Bowie, R. C. K. 2008. Phylogenetic relationships within Passerida (Aves: Passeriformes): a review and a new molecular phylogeny based on three nuclear intron markers. Molecular Phylogenetics and Evolution 48, 858-876.

Olsson, U., Alström, P., Ericson, P. G. P. & Sundberg, P. 2005. Non-monophyletic taxa and cryptic species – Evidence from a molecular phylogeny of leaf-warblers (Phylloscopus, Aves). Molecular Phylogenetics and Evolution 36, 261-276.

Saether, B. 1963. Mechanisms of interspecific spacing out in a territorial system of the Chiffchaff, Phylloscopus collybita, and the Willow warbler, Phylloscopus trochilus. Ornis Scan 14, 154-160.

Darren Naish About the Author: Darren Naish is a science writer, technical editor and palaeozoologist (affiliated with the University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs but has an avid interest in all things tetrapod. His publications can be downloaded at darrennaish.wordpress.com. He has been blogging at Tetrapod Zoology since 2006. Check out the Tet Zoo podcast at tetzoo.com! Follow on Twitter @TetZoo.

The views expressed are those of the author and are not necessarily those of Scientific American.





Rights & Permissions

Comments 86 Comments

Add Comment
  1. 1. Trisdino 3:16 pm 08/5/2014

    Those are some really beautiful pictures. Lovely animals they are, perhaps not my favorite birds, corvids and parrots hold that spot, but nevertheless some very pretty animals. The birds found around here are mostly a rather dull sort, not sure of their english name, the local(Danish) name is “grå spurve”, which means grey sparrow, but I have not been able to identify their specific species. Whatever the case, they are quite adorable, cheery little fellows, leaping around and all.

    I appear to have gotten quite sidetracked, huh, anyway, will we be seeing more on (extant)birds in the not so distant future? I would love to read a post on the aforementioned corvids.

    Link to this
  2. 2. Halbred 3:20 pm 08/5/2014

    “We’ve got to keep all these chiff-chaffs from making such a riff-raff!”

    Link to this
  3. 3. BrianL 4:36 pm 08/5/2014

    A warning if you ever want to cover *all* passerines: Just recently, I finished my own ‘Passerine of the day’ series on Facebook, where I tried to do a family a day, with a single species pictured and a short text (most of my Facebook followers are not exactly zoologically inclined). My goal was to go through the whole diversity of passerines as presented by the TIF Checklist, from acanthisittids to tanagers. Even throwing a few very small families together a few times, I needed a massive 112 installments to get through the whole bunch. Since there were a few days along the way that I couldn’t post an update, the whole series took me about 120 days. If you want to do the same and actually cover each family in debt, prepare to need a few years rather than just one.

    That being said, and I’m far from unbiased at this point, I think passerines are horribly oversplit even when compared to other birds. While I know, say, nine-primaried oscines are at times merged into a single or very few families, this is hardly normal practise (I didn’t do it myself in my series either). But if these guys, with splits presumably dating back to only Miocene times, get split into various families, surely the same should apply to cuckoos, pigeons and especially anatids?

    I know, ‘all taxonomy is arbritary’ and different families are not comparable, but it does seem weird from the perspective of the ornithologists who initially made these classifications and presumably *did* believe that the different avian families they recognised were comparable in that sense. Is it just the enormous number of passerines that resulted in such splitting? I’d also dare claim this splitting has become worse as the extremely tangled passerine family tree has become better known. I feel there is something to be said for Sibley & Monroe’s enormous passerine families, even though some were extremely bloated.

    Link to this
  4. 4. Heteromeles 4:59 pm 08/5/2014

    Erm, so the prevalence of warblers in North America and Europe proves that there were no oceans in the Cenozoic, and that’s where Noah ran aground and released all the birdies after the PETM Flood, and this all disproves climate change?

    I can’t think of anything brilliant to say about warblers (I’m clueless about the little cuties), except that this looks a lot like the Asclepiadaceae/Apocynaceae and Apiaceae/Araliaceae patterns seen in plants. For the zoologists, this is a reference to very distinct north temperate families actually being distinct little clades within much larger, and more messy, largely tropical families that were traditionally seen as totally distinct until molecular phylogenetics came along. One gets the odd idea that the tropics are full of evolving species, for some reason.

    Good article, but when are you going to get that genius fellowship to finish your coverage of Passeriformes?

    Link to this
  5. 5. Tayo Bethel 7:33 pm 08/5/2014

    Dr> Naish:

    To cover all Passeriformes… you should probably write a big, big book on Passeriformes. It would take years, same as blogging.
    Any plans to write about Corvita?

    Link to this
  6. 6. Christopher Taylor 8:43 pm 08/5/2014

    The presence of passerines on all continents obviously indicates Pangaean origins for the clade. The distribution of the Vireonidae in particular, in South America and eastern Asia (as revealed by molecular analyses), is a result of China being positioned close to Gondwana during the Devonian period, which provides us with a minimum Famennian age for the Erpornis-Vireo split. Come on, prove me wrong.

    Link to this
  7. 7. Christopher Taylor 8:53 pm 08/5/2014

    On a more serious note:

    But if these guys, with splits presumably dating back to only Miocene times, get split into various families, surely the same should apply to cuckoos, pigeons and especially anatids?

    It’s an artefact of history, isn’t it? Whenever a passerine ‘family’ has been shown to be para-/polyphyletic, it’s been split up. Transferring a taxon from one family to another doesn’t appear to have entered the equation very often. In the case of non-passerines, most of the Wetmore families have remained robustly monophyletic, so there hasn’t been the same drive to divide them.

    The worst case I can recall encountering (other than the establishment of the name ‘Calcariidae’, when the very reference cited as authority for that name’s priority indicated that it should have been called ‘Plectrophenacidae’) was the original establishment of the family Pnoepygidae by Gelang et al. 2009. Their analysis indicated that Pnoepyga was not a timaliid, but there were not many species sampled from the clade which it did get placed in. There was not really adequate data, I thought, to establish that it shouldn’t have been placed in some pre-existing family such as Pycnonotidae.

    Link to this
  8. 8. SeanMcCabe 10:35 pm 08/5/2014

    Could someone give a brief introduction to the major passerine clades? I’m not familiar at all with them. I’m more at home with non-avialan archosaurs.

    Link to this
  9. 9. naishd 7:31 am 08/6/2014

    More on this later: but, as Chris says, our ideas about which taxa deserve ‘families’ (or ‘orders’ or whatever) are based on tradition, bias and social inertia more than anything else – it’s very much a human endeavour, not necessarily a reflection of phylogenetic ‘reality’.

    Sean: best course of action is to attack the literature, and there’s a lot of it! For MAJOR passerine clades, have you seen my review of bird diversity in The Complete Dinosaur, 2nd edition?

    Link to this
  10. 10. John Harshman 8:05 am 08/6/2014

    What a mess those passerines are (which is why I try to avoid them at all times). Every time you look, some genus or family turns out to be polyphyletic, or belong to the wrong superfamily, or whatever.

    I’ll have to give Johansson et al. (2008) another look. It had been my impression that Certhioidea was well enough established as the sister group of Muscicapoidea and that there was at least some evidence that Paridae was the sister group of Sylvioidea.

    You might also add the reference in which the Australasian origin (and very few escapes therefrom) of oscines was first worked out, Barker FK, Barrowclough GF, Groth JG. 2002. A phylogenetic hypothesis for passerine birds; Taxonomic and biogeographic implications of an analysis of nuclear DNA sequence data. Proceedings of the Royal Society of London, Series B, 269:295-308.

    Also, my sympathies that you have no parotids in Europe. That’s what warblers are supposed to look like.

    Link to this
  11. 11. John Harshman 8:07 am 08/6/2014

    Spell check has for unknown reasons “corrected” the word parulids in that last sentence. I’m sure you have plenty of parotids.

    Link to this
  12. 12. BrianL 8:39 am 08/6/2014

    @SeanMcGabe:

    I think the TIF Checklist might greatly help you here, though it doesn’t show pictures but just gives a very up to date and commented-on list of all living passerines.

    http://www.jboyd.net/Taxo/List13.html

    Link to this
  13. 13. BrianL 8:44 am 08/6/2014

    @ John Harshman:
    Clearly, you’re wrong! Warblers should look like the species in the genus *Sylvia* with their generally dignified sober body colour and assertive black or red caps. What’s more, they should belong to a clade of other mainly insectivorous and fairly inconspicuous Old World songsters! Parulids are merely gaudy and weakbilled finches attempting to look like real warblers and even like real trushes that could not even cross Beringia with their paltry nine primaries!

    Link to this
  14. 14. naishd 8:57 am 08/6/2014

    John (comment 10): competing phylogenies find utterly different topologies for Passerida… in addition to the Johansson et al. (2008) topology shown above, Barker et al. (2004) found ((Sylvioidea + Paridae) + (Passeroidea + Muscicapoidea)) and Nabholz et al. (2010) found (Muscicapoidea + ((Paridae + (Sylvioidea + Passeroidea)))! On certhioids, they’re identified (though not named as a distinct lineage) as sister-group to Muscicapoidea in Jønsson & Fjeldså’s (2006) supertree, and in a polytomy with Muscicapoidea and Passeroidea in Cracraft et al. (2004).

    This is not meant to be an exhaustive discussion, of course.

    Refs – -

    Barker, F. K., Cibois, A., Schikler, P., Feinstein, J. & Cracraft, J. 2004. Phylogeny and diversification of the largest avian radiation. Proceedings of the National Academy of Sciences 101, 11040-11045.

    Cracraft, J., Barker, F. K., Braun, M., Harshman, J., Dyke, G. J., Feinstein, J., Stanley, S., Cibois, A., Schikler, P., Beresford, P., García-Moreno, J., Sorenson, M. D., Yuri, T. & Mindell, D. P. 2004. Phylogenetic relationships among modern birds (Neornithes): towards an avian tree of life. In Cracraft, J. and Donoghue, M. (eds) Assembling the Tree of Life. Oxford University Press (Oxford), pp. 468-489.

    Jønsson, K. A. & Fjeldså, J. 2006. A phylogenetic supertree of oscine passerine birds (Aves: Passeri). Zoologica Scriptca 35, 149-186.

    Nabholz, B., Jarvis, E. D. & Ellegren, H. 2010. Obtaining mtDNA genomes from next-generation transcriptome sequencing: A case study on the basal Passerida (Aves: Passeriformes) phylogeny. Molecular Phylogenetics and Evolution 57, 466-470.

    Link to this
  15. 15. Yodelling Cyclist 9:23 am 08/6/2014

    @Christopher Taylor: I’ll leave the job of disproving that to Heine, my pet Yeti. No one’s ever proved that he doesn’t exist either.

    Link to this
  16. 16. John Harshman 10:50 am 08/6/2014

    Darren,

    I think what Nabholz et al. show is that sparse sampling of mt genomes give you little in the way of result. The nodes connecting superfamilies have very weak support (except in the Bayesian analyses, where you can get 100% support for anything). I think the support for (Sylvioidea, (Passeroidea, (Muscicapoidea, Certhioidea))) is better than your figure would suggest. In addition to what you cite here, there’s Sheldon, F. H., and F. B. Gill. 1996. A reconsideration of songbird phylogeny, with emphasis on the evolution of titmice and their sylvioid relatives. Syst. Biol. 45:473-495. And that provides support for the position of parids too. But it would be nice to have a multilocus phylogeny with dense taxon sampling.

    All of which has little to do with chiffchaffs; my apologies.

    Link to this
  17. 17. Dartian 11:01 am 08/6/2014

    Darren:
    Willow warblers are somewhat larger so tend to have the advantage if they occupy a habitat first

    Chiffchaffs, however, return earlier in the spring to their northern European breeding grounds, which presumably gives them a competitive edge.

    Trisdino:
    I would love to read a post on the aforementioned corvids.

    Nooo! Not corvids yet! They get pretty much attention already – and they have in fact been the subjects of a couple of Darren’s previous articles. There are other passerine groups too that are more deserving of a Tet Zoo treatment. Speaking for myself, I wouldn’t mind reading about (e.g.) wagtails, nuthatches, or Old World orioles first.

    Link to this
  18. 18. Lars Dietz 11:04 am 08/6/2014

    On passeridan phylogeny, I think the latest study based on a large dataset is Alström et al. (2014), which found well-supported Sylvioidea/Paroidea/Stenostiridae/Hyliota and Muscicapoidea/Certhioidea/Bombycilloidea/Elachura clades. The relationships between these clades, Passeroidea, and Regulidae is poorly resolved.
    It may be interesting that long-tailed tits/bushtits (Aegithalidae), which were traditionally not included in Sylviidae, are also closely related to Phylloscopidae and Cettiidae within Sylvioidea. They’re mainly an East Asian family with one species each in Europe and North America. At least the European species is notable for an extreme level of cuteness and fluffiness, especially in juveniles.

    Link to this
  19. 19. naishd 11:19 am 08/6/2014

    Ah, I was unaware of Alström et al. (2014) until now, thanks for that. I love how the Proc B website says ‘Free to you’, but then takes me to a paywall when I click to get the pdf.

    Henry (comment # 17): yes, good call on the previous Tet Zoo corvid articles. Next: tits, nuthatches, treecreepers (though not necessarily all together).

    Link to this
  20. 20. M Tucker 11:34 am 08/6/2014

    Great topic. Keep the birds coming.

    Link to this
  21. 21. DavidCerny 11:40 am 08/6/2014

    There is also Hugall and Stuart-Fox’s (2012) huge analysis (4128 species, 11 nuclear + 7 mitochondrial genes), which recovered ((Sylvioidea, Stenostiridae), ((Muscicapoidea, Bombycilloidea), (((Certhioidea, Regulus), (Hyliota, Paroidea)), Passeroidea))).

    Link to this
  22. 22. naishd 11:43 am 08/6/2014

    You see, I deliberately left these references out to give you something important to say in the comments :)

    Link to this
  23. 23. Heteromeles 12:31 pm 08/6/2014

    Interesting sidebar (or possibly, attempt to derail the thread :D ): I wonder if there’s a “personality” issue around the passeriform researchers that leads to the current crazy state of their systematics. Yes, this is the same thing as cultural inertia, I guess.

    What I’m thinking about are the jokes about the different personality types who get attracted to different plant families. People who work on grasses, ferns, and mosses tend to get pigeon-holed as geeky and sexually repressed, mostly because these plants are flamboyantly sexual and hard to identify. This is somewhat of a mis-cue, because all three groups are lead lives of deep sexual deviancy when compared to heteronormal humans. But I digress. People who study orchids are stereotyped as being rather flamboyant, as well as nerdy and rather manipulative

    I’m wondering if there are similar stereotypes among ornithologists. I certainly get the differences between, say, raptor specialists and waterfowlers, but what about the, well, warblerologists? Are they a bunch of alpha-nerd splitters who like to show off their geek prowess by cataloging every subtype of warbler call as unique, or is there something else going on?

    Link to this
  24. 24. Yodelling Cyclist 1:17 pm 08/6/2014

    A question from the peanut gallery:

    When it comes to mtDNA studies, how is the possibility of hybridisation events handled? How well do modern phylogenetic techniques deal with such events?

    How do zygodactylids relate to passerines?

    All the best
    Yod

    Link to this
  25. 25. John Harshman 1:36 pm 08/6/2014

    All I am able to find for “Hugall and Stuart-Fox (2012)” is a paper in Nature about color polymorphism in non-passerines. What’s all this then?

    And I can’t break the paywall for Alström et al. (2014).

    Link to this
  26. 26. John Harshman 1:47 pm 08/6/2014

    Here, however, is the summary tree from Alström et al., which has fairly good support for Certhioidea + Muscicapoidea and Sylvioidea + Paroidea/Stenistiridae/Hyliotis, but no support for relationships among Passeroidea, Sylvioidea, and Muscicapoidea/Certhioidea.

    Regulus also continues to annoy; it’s the Opisthocomus of passeridans.

    Link to this
  27. 27. John Harshman 3:35 pm 08/6/2014

    When it comes to mtDNA studies, how is the possibility of hybridisation events handled? How well do modern phylogenetic techniques deal with such events?

    Depends on the scope of the study. If we’re talking about a few closely related species, you can sample several individuals in a population and thus find individual hybrids (or at least that would be one explanation for results discordant with morphology). If we’re talking about some broad taxon in which only one exemplar per genus is sampled, it’s unlikely to matter, as one species in the genus is as good a sample as another, and any really ancient introgression (in which mt genomes are replaced in an entire species) is also unlikely to matter. Modern phylogenetic techniques don’t deal with such events at all; the mitochondrial tree estimates the phylogeny of the mitochondria without regard to what bodies they have been packaged in. Now, if you combine mitochondrial and other data, there are methods that will jointly estimate the species tree and all the gene trees and will enable you to see discordance among gene trees; hybridization would be one interpretation.

    How do zygodactylids relate to passerines?

    I believe they have usually been interpreted as the sister group of passerines. Given that parrots are the living sister group, that makes for interesting possibilities.

    Link to this
  28. 28. vdinets 3:55 pm 08/6/2014

    Considering how uniform all passerines are, you could describe just one species in detail and be done with it :-)

    Link to this
  29. 29. DavidCerny 4:05 pm 08/6/2014

    @ John Harshman #25:

    All I am able to find for “Hugall and Stuart-Fox (2012)” is a paper in Nature about color polymorphism in non-passerines. What’s all this then?

    Yes, that’s the right paper; sorry that I forgot to include the whole citation. Look in the supplementary information. ;-) In order to test their hypothesis, they inferred species-level phylogenies for accipitrids, falcons, gamefowl, owls, Strisores, and all passerines that were represented in GenBank.

    Link to this
  30. 30. Tayo Bethel 4:09 pm 08/6/2014

    Another question from the peanut gallery. If parrots and zygodactylids are sister-groups to Passeriformes, how does the Coraciiformes-Pisciformes clade relate to passerines?

    Link to this
  31. 31. John Harshman 4:36 pm 08/6/2014

    how does the Coraciiformes-Pisciformes clade relate to passerines?
    They’re both parts of “land birds” or Telluraves, but there’s no good resolution beyond that.

    Link to this
  32. 32. John Harshman 4:52 pm 08/6/2014

    Look in the supplementary information.

    OK, that’s bizarre. All that effort and they never refer to passerines in the abstract or present a figure even in the supplementary information. Further, that has to be the sparsest supermatrix on record. And the trees are in a difficult to access format.

    Link to this
  33. 33. DavidCerny 5:35 pm 08/6/2014

    They’re both parts of “land birds” or Telluraves, but there’s no good resolution beyond that.

    It would be bizarre to take issue with this claim on the basis of analyses that you co-authored, but isn’t there rather consistent (albeit low) support for the Afroaves/Australaves divergence within landbirds from several large independent nuclear gene datasets?

    All that effort and they never refer to passerines in the abstract or present a figure even in the supplementary information.

    … what? The next-to-last sentence of the abstract: “This is corroborated by evidence from a species-level molecular phylogeny of passerines, incorporating 4,128 (66.5%) extant species, that polymorphic species tend to be younger than monomorphic species.”

    And the trees are in a difficult to access format.

    I used this to visualize them: http://etetoolkit.org/treeview/. The plugin gave me working URLs for the resulting pictures, but they appear to have stopped functioning.

    Link to this
  34. 34. John Harshman 6:11 pm 08/6/2014

    isn’t there rather consistent (albeit low) support for the Afroaves/Australaves divergence within landbirds from several large independent nuclear gene datasets?

    Not to my knowledge. There’s quite good support for Australaves but nothing I would call support for Afroaves in any analysis. In fact there’s some evidence contradicting it: Suh et al. 2011, in which Coliiformes is sister to all other Telluraves. McCormack et al. 2012 find Afroaves, with no support, in their Bayesian analyses, but their ML and species-tree analyses contradict it, again with no support. Kimball et al. 2013 contradict it. It may quite possibly exist, but I don’t see much evidence. What other independent data sets did you have in mind?

    I used this to visualize them

    I can’t even extract the Newick tree from the PDF.

    Link to this
  35. 35. DavidCerny 8:08 pm 08/6/2014

    @ John Harshman #34:

    What other independent data sets did you have in mind?

    None, I guess. I mainly relied on the poorly supported 416-locus Bayesian tree from McCormack et al. (2012). I was also willing to take their 1,541-locus ML and Bayesian trees as broadly supporting Afroaves, since the only difference from the original hypothesis was in the position of mousebirds, which are notoriously jumpy. I’d also say that while their species tree doesn’t support Afroaves, the giant polytomy it shows is compatible with it, so it can’t be said to contradict it. The PhyloBayes and unpartitioned ML analyses in Wang et al. (2011) also support the monophyly of Afroaves, but that probably isn’t conclusive due to their limited taxon sampling.

    There’s also some weak suppport for Afroaves in Kimball et al. (2013), and the good news is that it doesn’t come from FGB-int7 (Figure 4), but it’s only present in the analyses which combine their new 31-locus alignment with the Hackett et al. data, so it doesn’t really count as independent evidence.

    … yeah, I probably overstated my case.

    I can’t even extract the Newick tree from the PDF.

    Does this help? Even the maximum zoom is still useless in the default online viewer, but you should at least be able to download it:

    http://drive.google.com/file/d/0B78GqfGeBIHuSzdkN21UWHRFVGs/

    Link to this
  36. 36. John Harshman 9:25 pm 08/6/2014

    Does this help?

    It does, a little bit. I can see the tree and read the taxon labels, but the support values don’t appear, just featureless balls. I think the analysis works OK as a rough guide for comparative studies, but I can’t bring myself to think of it as a serious phylogenetic hypothesis, at least not one that adds to the published analyses that furnished the backbone.

    Link to this
  37. 37. CS Shelton 10:42 pm 08/6/2014

    Thrushes being connected to mynahs makes intuitive sense to me because in the videos I’ve seen, old world blackbirds (thrushes) sound a lot like starlings (mynahs). This could of course be way off, the way things go.

    Link to this
  38. 38. CS Shelton 10:57 pm 08/6/2014

    vdinets- lumpier than thou. :)

    Link to this
  39. 39. vdinets 8:52 am 08/7/2014

    CS Shelton: What, you don’t recognize passerines even as a family-level group? Wow…

    Link to this
  40. 40. Zoovolunteer 1:42 pm 08/7/2014

    Getting back to chiffchaffs – having seen the Canary Island Chiffchaff on Tenerife this year although it is visually very similar to mainland birds, there are some interesting ecological variations. There are several endemic flowers on the islands that appear to be adapted for bird pollination, and at least today the chiffchaff seems to be the main pollinator. There are no sunbirds or similar on the islands today to compete, so it seems to be filling that niche in part.

    Link to this
  41. 41. Tayo Bethel 2:26 pm 08/7/2014

    ‘Do passerines show any variationin body shape?

    Link to this
  42. 42. vdinets 11:33 am 08/8/2014

    Tayo Bethel Not much if you pluck them. Legs and bills differ a bit, plus there is a small difference in wing length, and some groups have upturned tails.

    Link to this
  43. 43. Yodelling Cyclist 12:05 pm 08/8/2014

    Tayo Bethel: Not sure. Let’s break out the old Origin of Species and take a look.

    Link to this
  44. 44. John Harshman 2:24 pm 08/8/2014

    Bills, I would say, differ extremely, even with such small groups as the vangas and Hawaiian honeycreepers. Legs, not as much, but variation encompassing both pittas and swallows is not small. And there’s plenty of variation in wing and tail plumage.

    Why do you ask? Are you trying to set objective criteria for taxonomic ranks? Good luck with that.

    Link to this
  45. 45. vdinets 7:47 pm 08/8/2014

    Well, there are also some display-related structures like wattles, pouches, etc., but display structures evolve very fast and are pretty much useless for higher-level taxonomy. As for bills, dimensions vary, but, to my knowledge, there are no cool structural innovations like filters in flamingos or fake teeth in mergansers. Crossbills and akiapolaau are probably the only ones with interesting bills.

    Link to this
  46. 46. CS Shelton 5:20 am 08/9/2014

    Not being an expert, I thought you might have been making a joke. They’re really that samey underneath the plumage? That’s amazing, considering the diversity of niches. Also, I’m reminded of peeps saying postcranial anatomy of ceratopsians being samey and some folks flexin about that, but as no one is contradicting you much, I’ll assume you’re right.

    It makes me think any given smallish Cretaceous “species” would probably be split thousands of ways if we had more soft tissue to check out.

    Link to this
  47. 47. CS Shelton 5:21 am 08/9/2014

    wah that paragraph was a mess.

    Link to this
  48. 48. naishd 5:44 am 08/9/2014

    One thing on the whole idea of passerines ‘all being alike’ once you get beyond the soft tissues: on the one hand, yes, these birds are generally fairly conservative as goes overall shape and proportions. But, once you start looking at the details, there’s a huge amount of variation – things like jaw shape, jaw joint anatomy, vertebral fusion, sternum size, wing length, foot robustness and digital proportions and size, ungual shape, pygostyle length, hip width and so on and on are all as variable as you’d expect for a group that includes perchers, climbers, arch-predators, probers, gapers, seed-eaters, aerial insectivores, and so on and on. The idea that given groups of animals are “all alike” once you go skin-deep is only ever superficially true – and it’s compounded by the fact that anatomical studies have mostly never been done in the first place, or are obscure and mostly unknown even when done.

    Link to this
  49. 49. vdinets 3:15 pm 08/9/2014

    Darren: of course there is some variation (we are talking about something like 5,000 species). But it is more or less similar to what is found in large family-level groups in nonpasserines, such as Phasianidae, Psittacidae, Accipiteridae, Anatidae, etc. Sorry, I didn’t mean to start another round of pulling ranks, just answered a question ;-) I am as tired of having to use rank-based taxonomy as anyone.

    Are you sure there weren’t enough anatomical studies on passerines? Would be surprising (disturbing, even), considering how much time and effort have people spent trying to figure out their phylogeny prior to giving up and switching to molecular-only approaches.

    Link to this
  50. 50. DavidMarjanovic 5:43 pm 08/9/2014

    Reading about passerines, are you? Well, here’s just a few books to get you started. Photo by Darren Naish.

    I shudder to think how much money you must have invested in books. I know you get review copies and other gifts, but – that many?

    Link to this
  51. 51. naishd 10:08 am 08/10/2014

    It’s true, I can’t stop buying books. I don’t know anyone who has a natural history library as good as mine.

    Link to this
  52. 52. Andreas Johansson 1:41 pm 08/10/2014

    If religion is opium for the masses, books are heroin for the intellectuals. :p

    (No intellectual myself, but I do share the book-buying bug. The worst part is references – taking a book off the to-be-read list and reading it is quite likely to leave the list longer.)

    Link to this
  53. 53. Dartian 4:04 am 08/11/2014

    CS Shelton:
    They’re really that samey underneath the plumage?

    Let’s put it this way: Do you think that a swallow and a lyrebird really would be that difficult to tell apart if they were plucked? ;)

    as no one is contradicting you much, I’ll assume you’re right

    Making such an assumption is, generally speaking,
    rarely a good idea, but in this particular case it’s especially unwarranted. You’re a clever fellow and you’ve been reading Tet Zoo for quite a while; haven’t you noticed by now that Vlad has the frustrating (and, to be blunt, unscientific) habit of presenting his personal opinions on various biological, not-common-knowledge subjects as facts?

    Was that too harsh on him? Not really. He is a repeat offender on this count and he’s doing precisely that same thing again in this very thread, for example, by saying that:
    - Passerines don’t show much variation in body shape – but as long as he doesn’t specify what he means by “much variation” that claim is just his opinion;
    - That the legs and bills of passerines only differ a bit – but as long as he doesn’t specify what he means by “a bit” that claim is just his opinion;
    - That there are only small differences in wing length between passerines – but as long as he doesn’t specify what he means by “small differences” that claim is just his opinion;
    - That passerine bills are only dimensionally distinct and that there are no “cool” structural innovations like filters or fake teeth*, and that crossbills and akiapolaau are probably the only ones with “interesting” bills. Do I even need to point out why there’s a problem with using criteria such as “cool” and “interesting” in what should be an objective scientific discussion?
    - That what anatomical variation there is amongst passerines “is more or less similar to what is found in large family-level groups in nonpasserines such as Phasianidae, Psittacidae, Accipiteridae, Anatidae, etc.” – but as long as he doesn’t quantify the variation within these groups (and thus facilitate a meaningful comparison with passerines) that claim is just his opinion.

    In short, if Vlad thinks that passerines are all the same anatomically**, fine, that’s his opinion. If he can back his claims up with actual facts, and thus disprove those who criticise him, all the better! But don’t you – or anyone else – just take his word in situations like this. It’s only sound to be sceptical of categorical, cocksure statements in scientific discussions, and to ask anyone who’s making them to back them up with proper references. And if they can’t/won’t do so, the safest bet is to disbelieve what they say this subject.

    * There are, as it happens, passerines with ‘fake teeth’; the South American plantcutters Phytotoma, which are highly specialised herbivores. They even chew their food (López-Calleja & Bozinovic, 1999).

    ** Incidentally; even if the claim that passerines are anatomically highly similar was correct, since when has Tet Zoo been only about anatomy anyway (I’m referring here to #28)? What about all the passerine diversity in, e.g., ecology and behaviour – could that be covered by describing only one species in detail? (Just to take one example, the differences in breeding biology within Passeriformes is quite probably at least as great as those within any other avian ‘order’.)

    Reference:
    López-Calleja, M.V. & Bozinovic, F. 1999. Feeding behavior and assimilation efficiency of the rufous-tailed plantcutter: a small avian herbivore. The Condor 101, 705-710.

    Link to this
  54. 54. Dartian 4:17 am 08/11/2014

    Darren:
    I don’t know anyone who has a natural history library as good as mine.

    Obviously, you haven’t seen mine. ;)

    (My current library is, alas, today much smaller than it once was – that’s the near-inevitable result of having moved several times.)

    Link to this
  55. 55. John Harshman 2:13 pm 08/11/2014

    Just to take one example, the differences in breeding biology within Passeriformes is quite probably at least as great as those within any other avian ‘order’.

    And greater than most. Passeriformes, for example, is one of only four orders to feature obligate brood-parasitism. There is the usual monogamy, polygyny, rare or frequent extra-pair paternity, and lekking. Dunnocks have some odd combinations, and fairy wrens are just weird.

    However, I can’t offhand think of any clear polyandry (with reversed sexual dimorphism) or anything like the stable threesomes in Anseranas Anyone? Anyone?

    Size differences seem unusually great too, from 4g to 1200g. Most orders don’t beat a factor of 100 between smallest and largest, and here we have 300 (though galliforms have greater variation).

    Link to this
  56. 56. Yodelling Cyclist 5:52 pm 08/11/2014

    Well, the body mass range matches palaeognaths – the little brown kiwi has a mass of ~1.2kg (IIRC) and the elephant bird was ~400kg, so there’s a factor of ~300 for you.

    Link to this
  57. 57. Yodelling Cyclist 5:52 pm 08/11/2014

    sorry, I meant little spotted kiwi.

    Link to this
  58. 58. John Harshman 6:57 pm 08/11/2014

    Ha! By the completely objective Linnean ranking, Palaeognathae isn’t an order.

    Link to this
  59. 59. vdinets 7:25 pm 08/11/2014

    Dartian: If I say something like “taxon A doesn’t have any cool features”, I expect everybody to understand that it is a personal opinion. How could it ever be a scientific claim? But I was answering a question that was also phrased in a relative, non-scientific way. If I asked you if the climate in the city where you live is good, it would be unreasonable for me to expect you to mail me a volume of meteorological statistics; all I can expect is something like “it’s OK” or “it sucks”.

    Now, you are repeatedly asking me to prove a negative. I cannot prove that taxon A doesn’t have much diversity in feature B. If you don’t agree with this claim, you are welcome to prove me wrong by comparing its diversity with other taxa of the same rank. However, when you are saying that a taxon with 5000 species has more diversity in (for example) size than a taxon with 5 species, I think (sorry, another personal opinion) that it’s an unfair comparison. You have to look at size distribution curves.

    Link to this
  60. 60. Dartian 8:43 am 08/12/2014

    Vlad:
    If I say something like “taxon A doesn’t have any cool features”, I expect everybody to understand that it is a personal opinion. How could it ever be a scientific claim?

    You said some quite more specific things than that. You made assertions about the degree of anatomical variation within a particular avian taxon, and stated in a matter-of-fact way that it’s not greater than the anatomical variation within other avian taxa. And you also gave (unsubstantiated) reasons as for why this is so: a supposed lack of diversity in, e.g., leg and bill dimensions.

    I was answering a question that was also phrased in a relative, non-scientific way.

    That’s no excuse not to stick to verifiable facts! Especially not on a popular science blog that is regularly read by literally thousands of biologists – including potential colleagues and employers. Don’t you care about your own professional reputation when you post comments? If you show such a cavalier attitude towards factual information here on Tet Zoo, why should anyone trust that you don’t do it in other circumstances too? Science it up, dude!

    If I asked you if the climate in the city where you live is good, it would be unreasonable for me to expect you to mail me a volume of meteorological statistics; all I can expect is something like “it’s OK” or “it sucks”.

    Who on earth would be satisfied with such a vague answer to that question? I certainly wouldn’t. I would certainly expect to learn more details.

    Now, you are repeatedly asking me to prove a negative.

    No, I’m not doing that at all. My message to you is that you should stop making claims that you can’t, or won’t, back up properly.

    However, when you are saying that a taxon with 5000 species has more diversity in (for example) size than a taxon with 5 species, I think (sorry, another personal opinion) that it’s an unfair comparison. You have to look at size distribution curves.

    If it’s just the range of variation in size that we’re interested in, why would it be relevant to look at the size distribution within taxa? (That would inform us about the average sizes of members within given taxa, but that’s a different question.)

    Link to this
  61. 61. Yodelling Cyclist 8:50 am 08/12/2014

    @John Harshman: Bugger, you’re absolutely right. But, ruling from the judges: are we really using Linnaean orders around here? Especially since, IIRC Struithniformes includes kiwis and ostriches, while Aepyornithidae includes the elephant birds despite the close relationship between kiwis and elephant birds?

    Link to this
  62. 62. DavidMarjanovic 10:34 am 08/12/2014

    Vlad has the frustrating (and, to be blunt, unscientific) habit of presenting his personal opinions on various biological, not-common-knowledge subjects as facts

    Well, yes; but the statements in this particular discussion all read to me as expressions of personal taste, often with a dose of sarcasm.

    Darren regularly says similar things. The difference is that Darren declares all tetrapods interesting and cool and awesome. :-)

    Ha! By the completely objective Linnean ranking, Palaeognathae isn’t an order.

    But Struthioniformes is, and some classifications lumped all “ratites” into Struthioniformes.

    Link to this
  63. 63. John Harshman 11:36 am 08/12/2014

    are we really using Linnaean orders around here?

    Of course we aren’t. Doesn’t anyone here understand irony? Ranks are arbitrary, but the controversy, such as it is, is about whether passerines are overspilt, and that’s an argument that requires us to take Linnean ranks seriously. If not, it becomes a non-controversy. So why should you compare paleognaths to passerines rather than paleognaths to neognaths and passerines to parrots? Sister groups are at least of equal age, which is something.

    In other words, this argument is nonsensical. But in order to talk about it seriously you have to consider it on its own terms. Vlad suggests that passerines aren’t variable enough to be an order. One can only point out their variability compared to other groups recognized (for whatever reason) as orders.

    But Struthioniformes is, and some classifications lumped all “ratites” into Struthioniformes.

    Which of course makes it paraphyletic, and so a bad idea. But you do point out how arbitrary Linnean ranks are.

    Link to this
  64. 64. Yodelling Cyclist 12:17 pm 08/12/2014

    You realise that a discussion of species concepts/arbitrary taxonomic ranking is worth (I think) three shots in the tetzoo podcast drinking game, right?

    My point being these things are good for something. Albeit for a debatable value of “good”.

    Link to this
  65. 65. Dartian 3:00 pm 08/12/2014

    David:
    the statements in this particular discussion all read to me as expressions of personal taste, often with a dose of sarcasm

    His first comment (i.e., #28) I considered a joke. Had he just left it at that, I wouldn’t have said anything. It’s when he kept at it, and when he went into specifics, that I had to start assuming that he was serious.

    And yes, he does have something of a history of making that kind of comments here on Tet Zoo, so this discussion fitted his general modus operandi. Although I do try to, I am unfortunately not entirely able to forget or to ignore that.

    Darren regularly says similar things.

    Perhaps it’s just that I interpret different people’s way of writing differently on the Internet, but I can usually tell when Darren is joking. Besides, even when Darren is joking, he usually backs up his statements with references. ;) (Heck, IIRC, Darren sometimes even includes references in his FaceBook comments!)

    Link to this
  66. 66. vdinets 3:07 pm 08/12/2014

    Dartian: now you are simply misquoting me.
    I said: “Legs and bills differ a bit, plus there is a small difference in wing length, and some groups have upturned tails.”
    You quote me as claiming “…lack of diversity in, e.g., leg and bill dimensions”. Which is directly opposite of what I actually sad. Don’t you care about your scientific reputation? ;-)

    Now, about size range. If taxon A has more extant species than taxon B, it means that in our study of size we have a larger sample size for A than for B, so even if both samples come from groups with the same size distribution, we are likely to find broader range in A. That said, I don’t see how size range is relevant to taxonomic rank; size differences can evolve very fast and be rather dramatic even between closely related taxa, as the rapid evolution of Little Eagle into Haast’s Eagle shows (not to mention various domestic breeds). But if you’d like to argue about sizes, size diversity in passerines is pretty much the same as in Phasianidae or Accipiteridae (I can give you the numbers if you’d like).

    Breeding biology in passerines is not mich more diverse than in Cuculidae (the latter have more advanced brood parasites than any passerine, as well as non-parasites, and both groups have cooperative breeding and various types of social structure… what else?). Besides, social structure can be extremely variable even within one species (look up Dunnocks).

    Plantcutters do have serrated bill edges, but it’s a very simple thing compared to complex bill structures in Anatids or flamingoes.

    Link to this
  67. 67. vdinets 3:31 pm 08/12/2014

    David: It’s not that I don’t consider all animals interesting and cool and awesome. Of course I do. But, being a scientist, I cannot deny the data that shows per-taxon levels of coolness and awsomeness to differ remarkably between taxa. My calculations (using an algorithm I can’t discuss until it’s published) show that per-species coolness coefficient for Accipteridae is 7.8, while for passerines it’s only 1.8, the lowest among major avian lineages. As for per-species awsomeness, Passerines fall below 2 on Naish Scale, while Phasianidae are at least at 6.

    Link to this
  68. 68. John Harshman 6:54 pm 08/12/2014

    I don’t see how size range is relevant to taxonomic rank

    What is relevant to taxonomic rank?

    size diversity in passerines is pretty much the same as in Phasianidae or Accipiteridae (I can give you the numbers if you’d like).

    Sure. It’s true for phasianids, especially if you include odontophorids; I do think that galliforms and passeriforms are unusual in their range of sizes. But accipitrids? I get a range of 68g (sparrohawk) to 6700g (Steller’s sea eagle). What have I forgotten?

    Link to this
  69. 69. vdinets 4:07 am 08/13/2014

    John Harshman: I think complex features that require lots of gene changes to evolve are more relevant for higher-level taxonomy. Major structural innovations, inventing amniotic eggs, this kind of thing.

    According to HBW, cinereous (a.k.a. Eurasian black) vulture can reach 12.5 kg.

    Link to this
  70. 70. Dartian 4:18 am 08/13/2014

    Vlad:
    now you are simply misquoting me

    Nice try, but as comment #53 should suffice to show, that’s not the case. (Btw, the English phrase ‘lack of diversity’ does not necessarily equal ‘absolutely no diversity’.)

    I don’t see how size range is relevant to taxonomic rank

    I wasn’t talking about ranks (except once, when I deliberately used scare quotes). I was talking about taxa – those taxa that you yourself chose as examples earlier.

    if you’d like to argue about sizes [...] I can give you the numbers if you’d like

    I wasn’t the one who brought up the subject of size. But since you volunteer to do so, by all means do give me/us the numbers.

    Breeding biology in passerines is not mich more diverse than in Cuculidae (the latter have more advanced brood parasites than any passerine, as well as non-parasites, and both groups have cooperative breeding and various types of social structure

    True, cuckoos are very diverse too regarding breeding biology. But AFAIK, there are no truly lek-breeding cuckoo species, nor any with as elaborate sexual dimorphism as (e.g.) whydahs or birds-of-paradise. Also, I don’t think there are any cuckoo species that build their nests in tree cavities, or any that use non-plant materials such as mud for making their nests (in contrast to certain passerines such as horneros and some swallows).

    Plantcutters do have serrated bill edges, but it’s a very simple thing compared to complex bill structures in Anatids or flamingoes.

    You mentioned mergansers earlier. They only use their ‘teeth’ for holding on to their prey. Plantcutters, as I’ve said, use their bills for chewing. How can you say that the latter adaptation less complex than the former?

    Link to this
  71. 71. Yodelling Cyclist 7:37 am 08/13/2014

    On the subject of acciptrids, if Haast’s eagle is permitted, then a maximum mass of 15000g is considered likely. So that’s a factor of >200.

    Link to this
  72. 72. Yodelling Cyclist 7:52 am 08/13/2014

    Also, if we are using orders, then we have to use accipitriformes, into which some have folded cathartidae, so one can argue for the Andean Condor’s consideration, at again 15kg. At this point, however, Linnaean taxonomy is just blowing raspberries at us if we are trying to understand evolution or discern patterns in the world, so we should almost certainly stop.

    Link to this
  73. 73. vdinets 12:50 pm 08/13/2014

    Dartian: I don’t see how comment #53 is relevant. English is not my first language, but I was taught in school that “lack of something” means pretty much the opposite of “there is a bit of something”, not the same thing.

    Breeding biology of many cuckoos is completely unknown; of those for which it is known, only 12 genera are not brood parasites, so they can’t be expected to have as much diversity in nesting behavior as passerines. That said, pied coucal nests in hollows (again, according to HBW), and some Chrysococcyx spp. have impressive sexual dimorphism.

    Anatids don’t chew their food because they have gizzards for that; however, they use their bill lamellae in an impressive variety of ways, from filter-feeding to stripping skin off seeds. Geese are also known to wash their food and to clean it of the mud by trampling on it (Ogilvie M. A. Wild Geese. Poyser Monographs, 2010, pp. 95-96).

    Size range in passerines is from 4.2 g (pygmy tyrants) to 1500 g (larger ravens), that’s the factor of ~350 (Wikipedia). In Accipiteridae it’s the factor of 160-200 (numbers in previous comments), while in Phasianidae it’s from 20 g (Asian blue quail) to 10 kg (wild turkey), the factor of 500 (HBW).

    Link to this
  74. 74. DavidMarjanovic 1:07 pm 08/13/2014

    My point being these things are good for something. Albeit for a debatable value of “good”.

    :-D :-D :-D :-D :-D
    Thread won!

    I think complex features that require lots of gene changes to evolve are more relevant for higher-level taxonomy. Major structural innovations, inventing amniotic eggs, this kind of thing.

    The trouble with that is that you can’t tell how many mutations were required by just looking at a morphological feature. Development biology has yielded lots of surprises, and it’s still a young field that hasn’t investigated most of what it could. Perhaps the amnion is, like, a duplication of the yolk sac and produced by a single mutation? Just speculating here…

    Link to this
  75. 75. vdinets 7:13 pm 08/13/2014

    David: That’s right, in most cases you can only guess, and this is one reason why rank-based taxonomy should be replaced with something better.

    Link to this
  76. 76. Dartian 3:29 am 08/14/2014

    Vlad:
    I don’t see how comment #53 is relevant.

    Funny, I could predict that response almost verbatim.

    Cuckoos [...] can’t be expected to have as much diversity in nesting behavior as passerines

    Rrright… but just a little while earlier you said that “Breeding biology in passerines is not m[u]ch more diverse than in Cuculidae.” So which is it; are cuckoos and passerines comparable regarding their breeding biology, or are they not comparable? Make up your mind, please! ;)

    Anatids [...] use their bill lamellae in an impressive variety of ways, from filter-feeding to stripping skin off seeds.

    You’re trying to change the subject. Previously you talked about diversity of bill structure – now you’re talking about bill use. They are not the same thing. (Corvids – which are passerines – have structurally speaking quite simple bills, but corvids surely use their bills in far more diverse ways than anatids use theirs.) Anyway, sticking to the question of bill structure way may note that it is indeed quite variable in passerines too. There are (just to take a few examples) the crushing bills of seed-eating finches, the curved bills of nectarivorous sunbirds, the hooked bills of carnivorous shrikes, the wood-probing bills of New Zealand callaeids, and the upward-pointing bills of flowerpiercers.

    Geese are also known to wash their food and to clean it of the mud by trampling on it

    That’s neat, but what does it have to do with bill structure diversity?

    Size range in passerines is from 4.2 g (pygmy tyrants) to 1500 g (larger ravens), that’s the factor of ~350 (Wikipedia). In Accipiteridae it’s the factor of 160-200 (numbers in previous comments), while in Phasianidae it’s from 20 g (Asian blue quail) to 10 kg (wild turkey), the factor of 500 (HBW).

    Thanks. Now what were those figures supposed to demonstrate again? (The parameters in this discussion seem to be shifting rather frequently; it’s getting harder to keep track.) That there is one avian ‘family’ (i.e., Phasianidae) where the size range differs more widely than in the ‘order’ Passeriformes? Interesting, but: so what?

    Link to this
  77. 77. John Harshman 9:55 am 08/14/2014

    Would that “something better” be rank-free names, or did you have something else in mind? Of course if names are rank-free, it’s impossible to argue that passerines are overspilt.

    Link to this
  78. 78. John Harshman 9:56 am 08/14/2014

    Oversplit.

    Link to this
  79. 79. vdinets 4:26 pm 08/15/2014

    Dartian: breeding biology and breeding behavior are not the same thing, just as bill shape is not the same thing as bill structure. And it was you who switched the subject from bill morphology to feeding behavior by using food-chewing by plantcutters as an argument.
    Anyway, I suggest wrapping up this discussion, as it is becoming even more meaningless than it was in the beginning :-)

    Link to this
  80. 80. vdinets 4:30 pm 08/15/2014

    John: If a rank-free naming and classifying system gets developed to the point when it is as convenient and easy to learn as the Linnean system, I think it would be a great cause for celebration.

    Link to this
  81. 81. DavidMarjanovic 7:50 am 08/16/2014

    Do you really want a naming and classifying system, or is a naming system enough?

    I’m on the publicity committee of the International Society for Phylogenetic Nomenclature… :-]

    Link to this
  82. 82. vdinets 1:30 pm 08/16/2014

    David: you cannot just name millions of species, unless you expect all future biologists to be electronic. There has to be some way of making it possible to learn and memorize the patterns of the tree.

    Link to this
  83. 83. DavidMarjanovic 7:58 am 08/17/2014

    Exactly: you name clades instead of classifying species. That’s in fact the title of a paper. :-)

    Link to this
  84. 84. Dartian 10:21 am 08/17/2014

    Vlad:
    breeding biology and breeding behavior are not the same thing

    Nobody talked about “breeding behavior”. You specifically and repeatedly talked about the “breeding biology” of cuckoos; then, in comment #73, in the same sentence you suddenly switched to talking about “nesting behavior” (which, incidentally, isn’t the same thing as “breeding behavior” either). I assumed that you just made an innocent mistake there. Are you now suggesting that your wording was deliberate after all, and thus an attempt to subtly change the subject again?! If so, you’re using a highly disingenuous debating technique.

    it was you who switched the subject from bill morphology to feeding behavior by using food-chewing by plantcutters as an argument.

    I wasn’t trying to change the subject. I mentioned plantcutter bills as a mere footnote (hence the asterisk) to my main comment.

    Anyway, I suggest wrapping up this discussion as it is becoming even more meaningless than it was in the beginning

    If you think this whole subdiscussion about passerine anatomical diversity – or lack thereof – was meaningless from the beginning, then why the hell did you start it in the first place (and then continued arguing as if you meant it)?! Do you intend to waste other people’s time on purpose? Playing the devil’s advocate like that is not very far from actual trolling.

    Link to this
  85. 85. vdinets 10:50 am 08/17/2014

    Dartian,
    I didn’t start this discussion. I merely answered someone’s question. For whatever reason, my answer provoked a personal attack from you. I tried to explain why I answered the question the way I did, but apparently you weren’t satisfied: you keep posting long replies, although it’s not clear to me what, if anything, you are trying to prove. I think it’s a meaningless discussion, and I’m not going to participate in it anymore, sorry.

    Link to this
  86. 86. naishd 11:05 am 08/17/2014

    85… 86 comments inspired by an article on leaf warblers. Not bad, not bad at all… Shame the comments are mostly not about leaf warblers though.

    Oh, and – good to see comments issue here has apparently been resolved.

    Link to this

Add a Comment
You must sign in or register as a ScientificAmerican.com member to submit a comment.

More from Scientific American

Scientific American Holiday Sale

Give a Gift &
Get a Gift - Free!

Give a 1 year subscription as low as $14.99

Subscribe Now! >

X

Email this Article

X