ADVERTISEMENT
  About the SA Blog Network













Tetrapod Zoology

Tetrapod Zoology


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

Blue tits: passerines seen from the peripheries (part II)

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


Email   PrintPrint



Preening Eurasian blue tit doing weird stuff with its wing: a bird that I photographed in April 2014. Photo by Darren Naish.

Today I want to talk more about passerines, and I know that this will make you happy. In particular: TITS!! Tits of several species are ubiquitous here in Europe. The two that are most frequently encountered here in southern England are the Great tit Parus major and Eurasian blue tit Cynanistes caeruleus. This article was originally about both species but it became over-long so I’ve ended up splitting it in two.

Oh yeah: again, the ‘from the peripheries’ idea alluded to in the title relates to the fact that western Europe has to be considered a far-flung outpost of the Passerine Empire (see the previous article for clarification). Read on for more about that.

As (just about) every bird-fan knows, all tits excepting the Yellow-browed tit Sylviparus modestus and Sultan tit Melanochlora sultanea were – until recently – grouped together in a large genus termed Parus, conventionally divided into the ten ‘subgenera’ Poecile, Periparus, Pardaliparus, Lophophanes, Melaniparus, Parus, Machlolophus, Cyanistes, Sittiparus and Baeolophus.

The best place to go when wanting to find out about the tits of the world.

But, as more data has come in, people have become increasingly unhappy with the idea that the species concerned should really be lumped into the one mega-genus, and the idea that those ‘subgenera’ should be stand-alone ‘genera’ has become popular (Gill et al. 2005, Gosler & Clement 2007, Johansson et al. 2013)… albeit not universally accepted among specialists (Päckert & Martens 2008). Decisions like this are always subjective, to a degree. However, in this particular case justification for the idea comes from the fact that morphologically aberrant tits that – in traditional taxonomy – would definitely warrant their own ‘genera’ are known to be deeply nested within ‘Parus’ of tradition. I’m referring to Pseudopodoces humilis, the Tibetan groundpecker: a tit so weird that it was long misclassified as a small ground-jay (and known as the Tibetan ground-jay). Not only is it a member of Paridae, it’s especially close to the Great tit and its relatives, the definitive Parus tits (James et al. 2003) (this has been covered briefly on Tet Zoo before: see links below).

Eurasian blue tit in typical foraging pose. Photo by Darren Naish.

The way the tit family is distributed indicates that eastern and tropical Asia was the main centre of its diversification, with molecular clock data suggesting that most divergences within Paridae happened in Asia during the Middle Miocene (Päckert et al. 2007, see also Johansson et al. 2013). At least two crossings into North America occurred during the Pliocene or Late Miocene; movements west into Europe and Africa happened at about the same time (Gill et al. 2005, Päckert et al. 2007). The taxa that belong to the blue tit complex (see below) diversified during the Pliocene, with the Mediterranean region being the apparent ‘centre’ of their evolution (Päckert et al. 2007). Again, western Europe is a ‘fringe’ region in biogeographical terms – but an important one for migrants that breed further south or east given the ridiculous amount of daylight it receives in summer.

Anyway, we’re here to talk specifically about the Eurasian blue tit. This is a small, garden-frequenting, woodland-dwelling tit, typically about 12 cm long and 11 g, and generally short-tailed and with a unique combination of black horizontal eyestripe, white cheek patches, blue crown and yellow breast. The sexes look similar but with practise you can distinguish the duller-blue females from the brighter males. It can occur at very high densities when conditions are right (as in, two pairs per hectare) and produces one of the largest clutches of any passerine: 7-12 eggs per clutch are about average, and 15 or 16 eggs are not uncommon. The record number is 22.

Diagrams (traced from photos) showing pollinating behaviour in Eurasian blue tits: image from Burquez (1989).

Blue tits of all sorts are typically insectivorous predators that eat huge numbers of caterpillars, aphids, micromoths and other small insects. They also eat seeds and buds, but I’m especially interested in the fact that they also seemingly serve an important role as pollinators. If you watch them often enough, you’ll see them reaching into flowers and emerging with pollen stuck to their faces. However, visiting flowers (and foraging from, or within, them) isn’t the same thing as pollinating them, and the apparent role of Eurasian blue tits as pollinators (especifically of introduced Fritillaria imperialis lilies planted in England) wasn’t brought to attention until 1985 (Ford 1985).

Blue tits are probably only part of a suite of Old World passerines that visit flowers to rob nectar: leaf warblers (discussed in the previous Tet Zoo passerine article) are among the others. What’s fascinating from a historical, evolutionary perspective is the suggestion that some of these birds might originally have been ‘flower-birds’ that formerly took advantage of specialised European plants that became extinct following the Pleistocene glaciations (Búrquez 1989). In the European region, such so-called ornithophilous plants are only present today on the Canary Islands. This puts a new spin on the idea – previously discussed in my article about the ‘ghosts’ of extinct birds – that ornithophilous plants present across Eurasia might indicate co-evolution with extinct hummingbirds, since it could mean that ornithophilous flowers co-evolved with known, extant Eurasian taxa like leaf warblers, not with hypothesised extinct hummingbirds.

Blue tit visiting flower blossum, presumably for nectar. Note the pollen stuck to the feathering close to the base of its bill. Photo by Darren Naish.

As is so often the case with widespread passerines, the Eurasian blue tit is polytypic – that is, there are several different forms, traditionally regarded as ‘subspecies’. A set of taxa that occur across northern Africa and on the different Canary Islands have conventionally been regarded as C. caeruleus ‘subspecies’ but they’re increasingly regarded as belonging to a distinct species: the African blue tit C. teneriffae. Furthermore, there are suggestions that C. teneriffae is a species complex and that further splitting is needed. Much debate has ensued (e.g., Kvist 2006, Sangster 2005, Kvist et al. 2005). I’m lucky enough to have seen African blue tits on several occasions – much as I’d like to talk about them right now, it’ll have to wait to another time. I never planned to write this much about blue tits in the first place anyway, gah! Until next time…

More passerines soon. For previous Tet Zoo articles on passerines, see…

Refs – -

Búrquez, A. 1989. Blue tits, Parus caeruleus, as pollinators of the crown imperial, Fritillaria imperialis, in Britain. Oikos 55, 335-340.

Ford, H. A. 1985. Nectarivory and pollination by birds in southern Australia and Europe. Oikos 44, 127-131.

Gill, F. B., Slikas, B. & Sheldon, F. H. 2005. Phylogeny of Titmice (Paridae): II. Species relationships based on sequences of the mitochondrial cytochrome-b gene. Auk 122, 121-143.

Gosler, A. G. & Clement, P. 2007. Family Paridae (Tits and Chickadees). In Del Hoyo, J., Elliott, A. & Christie, D. A. (eds) Handbook of the Birds of the World. Lynx Edicions, Barcelona, pp. 662-744.

James, H. F., Ericson, P. G. P., Slikas, B., Lei, F.-M., Gill, F. B. & Olson, S. L. 2003. Pseudopodoces humilis, a misclassified terrestrial tit (Paridae) of the Tibetan Plateau: evolutionary consequences of shifting adaptive zones. Ibis 145, 185-202.

Johansson, U. S., Ekman, J., Bowie, R. C. K., Halvarsson, P., Ohlson, J. I., Price, T. D. & Ericson, P. G. P. 2013. A complete multilocus species phylogeny of the tits and chickadees (Aves: Paridae), Molecular Phylogenetics and Evolution 69, 852-860.

Kvist, L. 2006. Response to “Taxonomic status of ‘phylogroups’ in the Parus teneriffae complex (Aves)” by George Sangster. Molecular Phylogenetics and Evolution 38, 290.

- ., Broggi, J., Illera, J. C. & Koivula, K. 2005. Colonisation and diversificiation of the blue tits (Parus caeruleus teneriffae-group) in the Canary Islands. Molecular Phylogenetics and Evolution 34, 501-511.

Päckert, M. & Martens, J. 2008. Taxonomic pitfalls in tits – comments on the Paridae chapter of the Handbook of the Birds of the World. Ibis 150, 829-831.

- ., Martens, J., Tietze, D. T., Dietzen, C., Wink, M. & Kvist, L. 2007. Calibration of a molecular clock in tits (Paridae)—Do nucleotide substitution rates of mitochondrial genes deviate from the 2% rule? Molecular Phylogenetics and Evolution 44, 1-14.

Sangster, G. 2005. The taxonomic status of ‘phylogroups’ in the Parus teneriffae complex (Aves): Comments on the paper by Kvist et al. (2005). Molecular Phylogenetics and Evolution 38, 288-289.

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 46 Comments

Add Comment
  1. 1. DavidMarjanovic 9:01 am 08/12/2014

    A blue tit at a cherry blossom? Will wonders never cease.

    Link to this
  2. 2. naishd 10:20 am 08/12/2014

    On pollen-eating and flower visitation by blue tits and other passerines, Felipe Martino has just reminded me of the following recent paper… [abstract here]

    da Silva, L. P., Ramos, J. A., Olesen, J. M., Traveset, A. & Heleno, R. H. 2014. Flower visitation by birds in Europe. Oikos DOI: 10.1111/oik.01347

    Link to this
  3. 3. John Harshman 11:43 am 08/12/2014

    The sexes look similar but with practise you can distinguish the duller-blue females from the brighter males.

    Especially if you can see into the near ultraviolet, which the birds can. I believe blue tits may have been the very first example of cryptic (to us but not to them) sexual dimorphism.

    Hunt S, Bennett ATD, Cuthill IC, Griffiths R. 1998. Blue tits are ultraviolet tits. Proceedings of the Royal Society of London, Series B, 265:451-455.

    Link to this
  4. 4. naishd 12:00 pm 08/12/2014

    Ah yes… I forgot to mention the UV stuff here; that’s because it’s in the next article (on Parus major). Good catch.

    Link to this
  5. 5. irenedelse 1:38 pm 08/12/2014

    Blue tits? Oh, the birds. And here I was, thinking we were talking about the long-expected Avatar sequel… :-D

    Seriously, though, they are beautiful birds. Not as ubiquitous as the great tit, but very interesting.

    Link to this
  6. 6. Halbred 2:22 pm 08/12/2014

    Oh man, irenedelse beat me to that joke! LOL

    Link to this
  7. 7. John Harshman 2:53 pm 08/12/2014

    This is definitely going to turn up on some google searches.

    Link to this
  8. 8. Yodelling Cyclist 3:27 pm 08/12/2014

    So is this series going to finish on the biggest tits in the UK?

    Link to this
  9. 9. naishd 3:29 pm 08/12/2014

    The series is not wholly tit-focused but the next article in the series does feature the biggest of the UK’s tits, yes. In fact, the species concerned is among the biggest tits in the world.

    Link to this
  10. 10. Heteromeles 3:34 pm 08/12/2014

    And, of course, we have to mention the immortal 1988 Naturearticle by Pettifor, Perrins, and McCleery. That one inspired newsroom guffaws all over the place.

    Link to this
  11. 11. Yodelling Cyclist 5:14 pm 08/12/2014

    How big are the world’s largest tits?

    Link to this
  12. 12. Dartian 3:37 am 08/13/2014

    Great tits are nice, but I hope that you’ll write about elegant tits too. ;)

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

    The biggest of the world’s 57 or so tits is the tropical Asian Sultan tit Melanochlora sultanea – a really interesting black and yellow species. The biggest individuals can be 20 cm long and weigh as much as 49 g (for comparison, chickadees and blue tits are about 10-14 g). This size goes for the nominate Sultan tit ‘subspecies’ – the others are smaller.

    Link to this
  14. 14. irenedelse 8:29 am 08/13/2014

    Considering the etymology of “tit” as in blue tits, is it still accurate to call Melanochlora sultanea a tit? Nothing small and morsel-sized there! ;-)

    Link to this
  15. 15. Heteromeles 11:29 am 08/13/2014

    @14: and you’re not grumbling about Melanochlora, which is “black-green,” for a bird that’s black and yellow? No love for Melanocitrina, I guess. :D

    Link to this
  16. 16. Yodelling Cyclist 12:22 pm 08/13/2014

    Since the comments seem to be stalling and we’re eight short: would it be reasonable to say that passerines are holding a similar ecological niche to the anurognathids?

    Link to this
  17. 17. Heteromeles 12:38 pm 08/13/2014

    Nah, I’m just grumpy that no fewer than three of the authors I generally follow (Naish, Stross, and Scalzi) are going to LonCon right now, and I can’t be there to bug them. Such is life. Perhaps we should hang this thread at 22 for a while, just to mess with Darren?

    Interesting non-sequitur is that Ol’ Google seems to think that Tit the bird is of Scandinavian derivation from an old word for sparrow, while tit from teat is Old English. So we’ve got a pair of etymological false friends here apparently. Of course, if we wanted to be politically correct, we’d pick an australasian term for these birds instead, and stop calling them tits entirely.

    Link to this
  18. 18. Yodelling Cyclist 12:40 pm 08/13/2014

    ….and are the New Zealand wrens the sister group (hope I have the right terminology) to passerines?

    Link to this
  19. 19. Yodelling Cyclist 12:43 pm 08/13/2014

    Wait, you mean Naish, Stross and Scalzi are all two hours by train from me and I have surgery tomorrow?

    I’m off to swear mightily at the NHS scheduling elves.

    Link to this
  20. 20. DavidMarjanovic 1:17 pm 08/13/2014

    would it be reasonable to say that passerines are holding a similar ecological niche to the anurognathids?

    No; being a huge and diverse group, passerines hold (or form, as some insist) a huge number of ecological niches, and anurognathids had huge eyes, so they probably hunted in twilight.

    ….and are the New Zealand wrens the sister group (hope I have the right terminology) to passerines?

    They are passerines; but they’re the sister-group to all other passerines put together, so you’re almost right! :-)

    Link to this
  21. 21. Zoovolunteer 2:26 pm 08/13/2014

    Having seen two of the Canary Island blue tits recently they seem to have rather different habitats than the European mainland species. On Tenerife I saw them in pine forest, though I expect they occur all over the island, but on Fuerteventura they were feeding in a palm tree, which looked rather odd. The Fuerteventura birds apparently respond to play back of African Blue Tit calls, but the birds on the other islands do not, and they are fairly distinct genetically. I gather that the Dutch Birding Association has them listed as separate species, which seems logical. A lot of other Canarian “subspecies” belong in the same category as well – the European Robins on Tenerife and Gran Canaria are probably full species (and may be distinct from each other as well).

    Link to this
  22. 22. John Harshman 3:02 pm 08/13/2014

    I’ll try to help the thread pick up:

    Pseudopodoces is one of several bird species that have in the past decade or so moved from one passerine superfamily to another. How many others can you name? And are there any good examples outside passerines?

    Regarding the former question, my favorite is Sapayoa. Regarding the latter, changing orders (e.g. turnicids) doesn’t count.

    Link to this
  23. 23. naishd 3:12 pm 08/13/2014

    Re: comment 22, what about all those passerines once regarded as sylviids, timaliids or muscicapoids but now regarded as ‘core corvoids’? Examples include Pteruthius, Colluricincla, Pachycephala

    Link to this
  24. 24. DavidCerny 4:47 pm 08/13/2014

    @ John Harshman #22:

    Another example is Kakamega, a sylvioid-turned-passeroid.

    @ Darren Naish #23:

    What was the original position of whistlers and shrike-thrushes? They were regarded as corvidans as far back as the late 80s (Sibley & Ahlquist 1987).

    Ref:

    Sibley CG, Ahlquist JE 1987 Avian phylogeny reconstructed from comparisons of the genetic material. 95–121 in Patterson C, ed. Molecules and Morphology in Evolution: Conflict or Compromise. London: Cambridge Univ Press

    Link to this
  25. 25. John Harshman 5:14 pm 08/13/2014

    Darren,

    I’m not counting anything pre-Sibley, as he established that there was such a thing as Corvoidea in the first place. I’m talking about more recent surprises, e.g. “Yuhina” (Erpornis) zantholeuca.

    Link to this
  26. 26. naishd 5:19 pm 08/13/2014

    DavidCerny (comment # 24): whistlers (pachycephalines) were regarded as a subfamily within Muscicapidae pre-Sibley.

    Link to this
  27. 27. naishd 5:33 pm 08/13/2014

    Oh, hey – larks have jumped from one ‘superfamily’ to another. Until recently, they were regarded as part of Passeroidea whereas recent studies have included them within Sylvioidea.

    Link to this
  28. 28. John Harshman 6:59 pm 08/13/2014

    By the way, this is an argument in favor of passerines all looking alike: you can’t even tell the corvoids from the passeroids, or the tyrannoids from the eurylaimoids, without a DNA sample.

    Link to this
  29. 29. Lars Dietz 7:44 am 08/14/2014

    Some other passerines that have jumped superfamilies:
    - Kakamega has been mentioned, but the other “arcanatorids” (an African clade of very basal passeroids) have in the past been placed in Turdidae s.l.
    - Paramythiid berrypeckers, from Passeroidea to Corvoidea
    - Chelidorhynx hypoxantha, from Rhipidura (Corvoidea) to Stenostiridae
    - Leonardina, from Timaliidae (Sylvioidea) to Muscicapidae
    - Elachura, from Timaliidae to a “superfamily-level” group of its own
    - Notiomystis (the hihi) from Meliphagidae to sister of Callaeatidae, in an unresolved position with Corvoidea and Passerida
    - Mohoidae (extinct Hawaiian “honeyeaters”), from Meliphagidae to Bombycillodea
    - Hylocitrea, from Pachycephalidae to Bombycilloidea
    Outside of passerines: Pluvianus (from Lari to Charadrii) is the only example I could think of at the moment.

    John Harshman: Sibley & Ahlquist actually mentioned a morphological character distinguishing “Corvida” from Passerida: the single vs. double pneumatic fossa of the humerus. I don’t know if there are exceptions. But for how many of the birds I listed here have any anatomical studies been done?

    Link to this
  30. 30. Varanussalvator 2:42 am 08/15/2014

    I was quite surprised to see pipits and wagtails included together with Old World sparrows in Passeridae in some classification schemes.

    Link to this
  31. 31. Dartian 7:05 am 08/15/2014

    Lars:
    Outside of passerines: Pluvianus (from Lari to Charadrii) is the only example I could think of at the moment.

    What about those two African ‘partridges/francolins’ that, according to molecular data, are actually most closely related to New World quail (Cohen et al., 2012)?

    Reference:
    Cohen, C., Wakeling, J.L., Mandiwana-Neudani, T.G., Sande, E., Dranzoa, C., Crowe, T.M. & Bowie, R.C.K. 2012. Phylogenetic affinities of evolutionarily enigmatic African galliforms: the stone partridge Ptilopachus petrosus and Nahan’s francolin Francolinus nahani, and support for their sister relationship with New World quails. Ibis 154, 768-780.

    Link to this
  32. 32. Lars Dietz 7:24 am 08/15/2014

    Dartian: I actually thought of those after writing my comment, but they just moved to another family, not superfamily. However, the reason for this is only that passerines are split much more than galliforms, I think the divergence times here are similar to those of some passerine superfamilies. Which again demonstrates how subjective ranks are.
    Oh, and within passerines I forgot the Malagasy “babblers” Newtonia and Mystacornis that turned out to be vangas (Corvoidea). And Hypocryptadius (the Cinnamon Ibon, from the Philippines), which moved from white-eyes (Sylvioidea) to being an insectivorous old world sparrow. In general, many species mentioned here were formerly classified as babblers (Timaliidae), which always was a wastebasket family. Ernst Hartert rhymed in the 1920s: “Was man nicht unterbringen kann, sieht man als Timalien an” (What one cannot classify, one regards as babblers), and this essentially didn’t change until molecular studies were done.

    Link to this
  33. 33. BrianL 10:28 am 08/15/2014

    Those famously undefinable old school babblers having been mentioned, note that *Picathartes* and *Eupetes* used to be babblers at one time and are now, together with *Chaetops* from the former Muscicapoidea in their own superfamily Picathartoidea, and probably are basal Passerida.

    There’s also the shrike-babblers jumping ship from the babblers to the vireos, deep in Corvida.

    Link to this
  34. 34. John Harshman 10:35 am 08/15/2014

    John Harshman: Sibley & Ahlquist actually mentioned a morphological character distinguishing “Corvida” from Passerida: the single vs. double pneumatic fossa of the humerus. I don’t know if there are exceptions. But for how many of the birds I listed here have any anatomical studies been done?

    Yes, I thought about mentioning that. A great many taxon assignments have been based on superficial anatomy of plumage, bill shape, and such. Looking at osteological and other internal anatomical characters in detail can often help, but there are so damn many passerines. However, returning to Paridae for a change, Pseudopodoces is a great example, as Helen James was able to place it in Paridae using osteological characters.

    Thanks for all the fine examples of superfamily-switching. This is one reason I try to avoid passerines as much as possible.

    Link to this
  35. 35. DavidMarjanovic 7:44 am 08/16/2014

    What one cannot classify

    Or “accommodate” or even “stow away”.

    Link to this
  36. 36. Felix2 3:33 pm 08/16/2014

    Passerine taxonomy is quite the mess. That’s why I have never really made an effort to understand it…New Zealand Wrens aren’t really wrens?!? You learn something new every day.

    Link to this
  37. 37. DavidMarjanovic 7:54 am 08/17/2014

    They’re literally as far from being wrens as a passeriform can!

    Link to this
  38. 38. Felix2 9:13 am 08/17/2014

    New Zealand…the land of oddities…

    Link to this
  39. 39. Dartian 4:32 am 08/18/2014

    David:
    They’re literally as far from being wrens as a passeriform can!

    The New Zealand wrens have never been thought by ornithologists (not even in the 19th century) to be actually related to the true wrens, have they?

    Link to this
  40. 40. DavidMarjanovic 9:39 am 08/18/2014

    Not that I know of, but I really don’t know the history of ornithology well. :-)

    Link to this
  41. 41. Yodelling Cyclist 3:04 pm 08/18/2014

    New Zealand wrens are really very old. Supposedly they’ve been distinct since the late Palaeocene, and really diverge from the rest of the passerines very early in the passerine radiation. This information is from brief googling, so should be taken with a pinch of salt.

    Suffice to say, that must have been a weird time (the late Paleocene) in the southern continents, with australia getting colonised by the australidelpha (presumably via antarctica), sloths and phorusrachids getting going in antarctica, plus whatever the hell the St. Bathan’s mammal lineage doing…whatever it was doing.

    Link to this
  42. 42. Lars Dietz 6:13 pm 08/18/2014

    I don’t know if anyone put NZ wren with true wrens, but G. R. Gray, in his influential “Hand-list” classified them as nuthatches (link).

    Link to this
  43. 43. Dartian 2:53 am 08/19/2014

    Lars:
    I don’t know if anyone put NZ wren with true wrens, but G. R. Gray, in his influential “Hand-list” classified them as nuthatches

    Wow, that was unexpected. Good find. Thanks, Lars!

    Link to this
  44. 44. Felix2 7:57 am 08/19/2014

    I had never done any research on New Zealand wrens. I just assumed…well, thats interesting. Nuthatches?!?!?

    Link to this
  45. 45. Christopher Taylor 8:37 pm 08/19/2014

    Seeing as the rifleman, the commonest of the New Zealand wrens (and one of only two species, these days), goes by the generic name of Acanthisitta, it doesn’t surprise me that it would be compared to a nuthatch (Sitta). I believe it does show the same sort of bark-gleaning behaviour as nuthatches.

    Link to this
  46. 46. Dartian 7:24 am 08/20/2014

    Christopher:
    as the rifleman [...] goes by the generic name of Acanthisitta, it doesn’t surprise me that it would be compared to a nuthatch (Sitta). I believe it does show the same sort of bark-gleaning behaviour as nuthatches.

    Hmm, good points about the rifleman’s behaviour; maybe its historical association with nuthatches wasn’t so totally off after all. (And the fact that it was indeed named ‘Acanthisitta‘ should have made that even clearer, but I failed to make that association.)

    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 Back To School

Back to School Sale!

12 Digital Issues + 4 Years of Archive Access just $19.99

Order Now >

X

Email this Article

X