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Tetrapod Zoology


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Historical ornithology 101, a Tet Zoo Guide

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


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Images by Emily Willoughby (top left), Matthew Martyniuk (bottom left), and John Conway (at right).

Several of the diagrams here are from my review of bird diversity and evolution (Naish 2012). For Tet Zoo articles on various of the subjects illustrated here, see…

Ref – -

Naish, D. 2012. Birds. In Brett-Surman, M. K., Holtz, T. R. & Farlow, J. O. (eds) The Complete Dinosaur (Second Edition). Indiana University Press (Bloomington & Indianapolis), pp. 379-423.

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.





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  1. 1. vdinets 11:57 am 07/6/2013

    What seems amazing to me is that birds often survive hitting windows without obvious long-term effects. Looking at their skulls, you’d expect serious fractures, particularly in those fragile-looking jugals. Of course, it’s usually small birds, so there isn’t much kinetic energy in the collision, but still…

    Link to this
  2. 2. David Černý 5:41 pm 07/6/2013

    Are “ratites” used just as a general ecomorphological grouping or as a clade? If it’s the latter, shouldn’t paleognaths consist of ostriches and everything else instead of (probably polyphyletic) “ratites” and tinamous?

    Link to this
  3. 3. naishd 6:14 pm 07/6/2013

    ‘Ratites’ is being used here in the most vernacular sense possible, not in the strict phylogenetic context. Indeed, if tinamous are deeply nested within Ratitae as several studies now indicate, ‘ratite’ as conventionally used is now similar to ‘fish’ – it’s a convenient term for a paraphyletic assemblage.

    Darren

    Link to this
  4. 4. John Harshman 7:33 pm 07/6/2013

    I’m resenting the “if” slightly, as it implies less assurance than we assuredly now have, what with the vast number of individual genes now all saying the same thing, including, after much tweaking, even the mitochondrial data. Not to mention a couple of morphological studies. In all, the result is more certain than the flamingo-grebe clade, or approximately as good as the assertion that the pope is Catholic.

    Did you really use that horrendous “Australavis”? Urk.

    Link to this
  5. 5. Troodon Man 12:29 am 07/7/2013

    Hi, Darren. I love troodontids, and I am very sad that they are extinct. Which animal alive today do you think would be the closest thing to a living Troodon? Thanks!

    Link to this
  6. 6. llewelly 1:07 am 07/7/2013

    “What seems amazing to me is that birds often survive hitting windows without obvious long-term effects. Looking at their skulls, you’d expect serious fractures, particularly in those fragile-looking jugals. Of course, it’s usually small birds, so there isn’t much kinetic energy in the collision, but still…”

    I wouldn’t place too much confidence in such observations. There are all manner of lasting damages which would not be obvious to an observer zooming by in a vehicle.

    Even an observer standing by the side of the road would miss many kinds of damage.

    Link to this
  7. 7. CS Shelton 2:30 am 07/7/2013

    Troodon- I’m not Darren or a scientist, but I’m going with small cats. Small active predators that snag prey with cool claws, mostly go for small and diverse prey – from arthropods to mammals to squamates to birds. Seems right to me.

    Link to this
  8. 8. vdinets 3:29 am 07/7/2013

    llewelly: I rescued a few of those, and they all happily took off after a short period of time (from twenty minutes to two days). Many of them ate normally before leaving. Of course, it’s impossible to be 100% sure without an X-ray, but they didn’t behave like they were in any pain. I am talking about birds that hit building windows, not cars.

    Link to this
  9. 9. BrianL 4:17 am 07/7/2013

    I am pleasantly surprised by your use of Metaves. Not that I dislike the hypothesis but because I was under the impression that it’s considered a very weak one these days. Am I wrong about that?

    Link to this
  10. 10. naishd 5:10 am 07/7/2013

    Thanks for comments. On resenting the “if” in “if tinamous are deeply nested within ratites” (comment # 3).. don’t take offence :) I tend to prefer the use of caveats when referring to phylogenetic hypotheses, though I see that I’m inconsistent (e.g., “birds are dinosaurs”, rather than “birds are almost certainly dinosaurs” etc.).

    Metaves (comment # 9): analyses are still recovering a clade that corresponds to Metaves. One recent example…

    McCormack, J. E., Harvey, M. G., Faircloth, B. C., Crawford, N. G., Glenn, T. C. & Brumfield, R. T. 2013. A phylogeny of birds based on over 1,500 loci collected by target enrichment and high-throughput sequencing. PLoS ONE 8(1): e54848.

    Darren

    Link to this
  11. 11. Gigantala 7:51 am 07/7/2013

    @CS Shelton: Except cats aren’t herbivores, don’t have ear asymmetry and wings.

    I don’t think there’s an analogue for troodonts nowadays, but fowl and extinct flightless owls are good “almost there”s

    Link to this
  12. 12. BrianL 8:03 am 07/7/2013

    @Darren:

    While I can see your point regarding the study you referred to, I’m not as confident as you are about this study supporting Metaves (though the devil is in the detail, hence probably your words ‘a clade that corresponds to Metaves’).
    The caveats are that pigeons are seemingly recovered as sister to the rest of Neoaves in the 416 loci tree while being ‘metavian’ in the 1541 loci tree, touracos and bustards are drawn into ‘Metaves’ in both and the hoatzins (and trumpeters) characteristically jump in and out of it. Note that only the 416 loci tree recognises what would correspond to Metaves as a clade whereas the early branching is largely unresolved in the other one. The ‘overall’ tree they have created doesn’t really recognise Metaves either. Unfortunately, mesites were not included. Cranes or rails weren’t either, though presumably they would group with the trumpeters. The kagu isn’t a major omission either as it consistently groups with the sunbittern in every study where it is included.
    So, using this study, I’d conclude that overall support for Metaves is still rather weak and if it exists, it would include some ‘traditional’ Coronaves. Note that I quite like the hypothesis of Metaves even if I’m being fairly critical of it here.

    Link to this
  13. 13. Lars Dietz 11:05 am 07/7/2013

    Concerning Metaves, have you seen the new paper by Kimball et al.? It shows that nearly all of the signal for this is in the beta-fibrinogen gene, and datasets not including this gene result in different topologies. Some of the trees also show a clade resembling Metaves (but excluding some members and including some other taxa), but in general they’re all different from each other depending on which genes are included. It seems the diversification was so rapid that it may be impossible to actually resolve it into a single bifurcating tree, which is also supported by the inconsistent retroposon insertion patterns found in some recent studies. There are apparently about 15 extant lineages that diverged around the same time, the largest of which being “landbirds” (Telluraves Yuri et al. 2013, called Dendrornithes in Darren’s tree) and “waterbirds” (Aequornithes).

    Link to this
  14. 14. David Černý 2:51 pm 07/7/2013

    @John Harshman:

    Did you really use that horrendous “Australavis”? Urk.

    It’s definitely nice to see that you formally corrected it in Yuri et al. (2013); I hope that Australaves (as well as Telluraves, Notopalaeognathae, etc.) catches on. Fortunately, it seems that few people have adopted the weird original spelling.

    Ref:

    Yuri T, Kimball RT, Harshman J, Bowie RCK, Braun MJ, Chojnowski JL, Han K-L, Hackett SJ, Huddleston CJ, Moore WS, Reddy S, Sheldon FH, Steadman DW, Witt CC, Braun EL 2013 Parsimony and model-based analyses of indels in avian nuclear genes reveal congruent and incongruent phylogenetic signals. Biology 2: 419–44

    Link to this
  15. 15. naishd 5:38 pm 07/7/2013

    Thanks for comments. The tree shown above only exists on Tet Zoo and the exact version hasn’t been published anywhere so, no, I haven’t used ‘Austalavis’ in print. In fact, I didn’t know about Yuri et al. (2013) until now, thanks, Lars and David.

    Darren

    Link to this
  16. 16. Troodon Man 7:21 pm 07/7/2013

    @ Gigantala,
    Actually, I think cats probably would be the modern-day equivalent of a Troodon. Troodons and cats are both intelligent nocturnal predators with large eyes and retractable claws. Therefore, I think a cat would be a very good match for a Troodon.

    Link to this
  17. 17. John Harshman 10:43 pm 07/7/2013

    I would agree that McCormack et al. don’t have any real support for Metaves — one Bayesian analysis finds weak support for a clade somewhat resembling Metaves. But there is a bit more reliable support for Coronaves, except that Opisthocomus wanders in from time to time.

    Are there any other publications that support Metaves or anything that’s very much like it?

    Link to this
  18. 18. Therizinosaurus 1:57 am 07/8/2013

    “It’s definitely nice to see that you formally corrected it in Yuri et al. (2013); I hope that Australaves (as well as Telluraves, Notopalaeognathae, etc.) catches on.”

    But there are no rules for naming such clades, so is it really a correction? I agree it goes against our normal conventions, but it’s not actually wrong. Indeed, if you did the reverse and named a genus of bird “Australaves”, the ICZN has no requirement that someone emmend it to “Australavis”. Thus you’re really just changing a name someone else published, and that seems wrong to me.

    Link to this
  19. 19. Chabier G. 3:58 am 07/8/2013

    Vdinets: After 16 years trying to rehabilitate wild animals, most of them birds, I can agree, birds seem to have more resistence to skull damage, perhaps cause of their light skull, pneumatized and with many elastic hinges, instead of being a solid box like that of mammals, cranium fractures are far rarer in birds than in mammals. But,after the cases I’ve seen, I think bird brain structure has something different, compared with mammals, birds can be alive (but not survive) for several days with parts of the brain uglily destroyed and out of the braincase. And about recovering after glass hittings, it´s up to the Kinetic energy, and then, to the body mass. Swallows used to survive and recover, blackbirds and sparrowhawks usually die immediately, kingfishers can be alive for some days…
    Last year we released a Golden Eagle that was struck down by a van running at 130 km/h, the bird broke the front carglass, falling into the vehicle. We had to sew a lot, but there were not fractures, and the evident neurological damages disapeared seven days later, it could fly normally 15 days later.

    Link to this
  20. 20. vdinets 9:28 am 07/8/2013

    Chabier: AFAIK, birds do have very different brain structure compared to mammals. There is virtually no cortex, and the entire volume is utilized much more effectively.

    Link to this
  21. 21. SciaticPain 11:19 am 07/8/2013

    Unfortunately birds brains, eyes, skins, and feathers are being fried, blinded and smattered by renewable energy solar panels in the California desert. Tens of thousands of mirrors are focused onto towers for energy production creating a type of solar flux blinding, burning, or even incinerating birds. Soaring birds, like eagles, which seek out such thermal updrafts may be getting especially hard hit. Migratory waterfowl may crash land on the glass panels, mistaking them for water. Because it is “green energy” feds are recalcitrant to intervene.

    http://www.kcet.org/news/rewire/solar/concentrating-solar/usfws-wants-moratorium-on-solar-power-towers.html

    http://www.kcet.org/news/rewire/solar/concentrating-solar/feds-
    weigh-in-on-solar-power-tower-threat-to-birds.html

    Link to this
  22. 22. David Marjanović 11:53 am 07/8/2013

    Indeed, if you did the reverse and named a genus of bird “Australaves”, the ICZN has no requirement that someone emmend it to “Australavis”.

    That could actually be automatic, in that genus names have to be singular; or “Australaves” could be automatically invalid. I’ll check (keeping in mind that the ICZN sucks at clearly expressing what earlier Commissions thought was obvious), and I’ll read Yuri et al. (2013).

    I just read Nishihara et al. (2009), which I had overlooked before. While the inference of Early Cretaceous placentals strikes me as rather silly, they present very strong evidence that Placentalia is for practical purposes a hard trichotomy.

    Last year we released a Golden Eagle that was struck down by a van running at 130 km/h, the bird broke the front carglass, falling into the vehicle. We had to sew a lot, but there were not fractures, and the evident neurological damages disapeared seven days later, it could fly normally 15 days later.

    …Wow.

    Link to this
  23. 23. Lars Dietz 12:50 pm 07/8/2013

    John Harshman: Yes, there was a clade similar to Coronaves found in those trees, but excluding core gruiforms, bustards and turacos (cuckoos were not included), which instead grouped with various “metavians”. As similar results are also found in some of the Kimball et al. trees, there seems to be some signal for that across the genome. Another result that’s found in both papers is the Eurypygiformes + Phaethontidae clade. Doesn’t seem to make much sense morphologically (although the kagu does vaguely look like a flightless tropicbird), but who knows.

    Link to this
  24. 24. David Marjanović 12:56 pm 07/8/2013

    Art. 11.8: “A genus-group name [...] must be, or be treated as, a noun in the nominative singular.” Looks like anything goes, but:

    Art. 26: “Assumption of Greek or Latin in scientific names. If the spelling of a scientific name, or of the final component word of a compound name [Art. 31.1], is the same as a Greek or Latin word, that name or that component is deemed to be a word in the relevant language unless the author states otherwise when making the name available.” That sounds like “aves” cannot be singular.

    Art. 30 expects us to know or look up the gender of Latin words, so I think this implies we’re expected to know or look up their number, too. (Too long to copy, so I’ve provided the link.)

    Art. 32.5: “32.5.1. If there is in the original publication itself, without recourse to any external source of information, clear evidence of an inadvertent error, such as a lapsus calami or a copyist’s or printer’s error, it must be corrected. [...]” Funnily enough, this argues we should consider such a hypothetical exchange of -e- and -i- either a typo or a mistake based on English pronunciation interfering with the ability to remember Latin spellings! It says we should not consider the spelling deliberate, because, after all, we’re not allowed “recourse to any external source of information”. …Except, apparently, the “standard Latin dictionaries” and “standard Greek dictionaries” of Art. 30.1. Great job at failing to express yourselves clearly, Commission!

    Finally, Art. 33.2.2 says: “The correction of an incorrect original spelling in accordance with Article 32.5 is a ‘justified emendation’, and the name thus corrected retains the authorship and date of the original spelling [Art. 19.2].”

    Link to this
  25. 25. Yodelling Cyclist 1:46 pm 07/8/2013

    For the non-specialists in the cheap seats, would anyone like to give a concise summary of the metaves hypothesis?

    Link to this
  26. 26. David Marjanović 2:18 pm 07/8/2013

    While I’m already talking about nomenclature, I have a bit to say about that of Yuri et al. (2013). Most of it is hidden in Supplementary Information 2. The meanings of P, Q and S aren’t explained anywhere in the paper or the supp. inf., and N and O are misapplied in fig. 3 (both A and B). None of the names is given a phylogenetic definition, making it difficult to apply them to different topologies. For comparison, I just checked Mayr (2011) (free pdf), and he did give Aequornithes* a phylogenetic definition (“the least inclusive clade containing Gaviidae and Phalacrocoracidae”), though he didn’t extend the same courtesy to Picocoraciae.

    BTW, it’s downright funny to read the exchange between Mayr (2011) and Yuri et al. (2013: supp. inf. 2) about Galloanserae vs. Galloanseres – both, following Sibley et al. (1988), treat -ae and -es as arbitrary rank-like endings that should be consistent between sister-groups, and they both don’t mention that the plural of anser (“goose”) is anseres – there’s simply no way to get from anser to “anserae”!

    Rant over.

    * Portmanteau of Latin aequor, “expanse of water”, and Greek ornithes, “birds”.

    Link to this
  27. 27. David Marjanović 2:24 pm 07/8/2013

    concise summary of the metaves hypothesis

    The idea that Neoaves consists of two clades, Coronaves and Metaves, where Metaves contains Strisores (“Caprimulgiformes” incl. Apodiformes), Eurypygiformes (Eurypyga + Rhynochetos), Pteroclidae/Pterocleidae/Pteroclididae*, Columbidae, Mesitornithidae, Mirandornithes (Phoenicopteridae + Podicipedidae), Phaethon, and a certain Opisthocomus hoazin.

    * I don’t know enough Greek or prevailing usage to tell which is correct.

    Link to this
  28. 28. Gigantala 3:13 pm 07/8/2013

    @Troodon Man: Provided cats are herbivorous and superprecocial, sure.

    Link to this
  29. 29. David Černý 3:14 pm 07/8/2013

    @Lars Dietz:

    Yes, there was a clade similar to Coronaves found in those trees, but excluding core gruiforms, bustards and turacos (cuckoos were not included), which instead grouped with various “metavians”.

    Maybe we could be charitable to the two names and extend the usage of “Metaves” and “Coronaves” to clades with slightly different content (after all, we’ve been doing that since the hoatzin jumped among coronavians in the Hackett et al. analysis). Of course, it wouldn’t hurt to have stronger support for the existence of such clades in the first place…

    @David Marjanović:

    I just read Nishihara et al. (2009), which I had overlooked before. While the inference of Early Cretaceous placentals strikes me as rather silly, they present very strong evidence that Placentalia is for practical purposes a hard trichotomy.

    At the risk of going off-topic, isn’t there rather robust support for the Atlantogenata hypothesis from post-2009 analyses?

    The meanings of P, Q and S aren’t explained anywhere in the paper or the supp. inf.

    That shouldn’t cause any confusion, though. P obviously stands for Neognathae, Q for Novaeratitae, and S for Palaeognathae.

    None of the names is given a phylogenetic definition

    They are given definitions, although the authors are a bit lazy about it: “The supra-ordinal clades listed in Table 1 are defined as the least inclusive clade comprising the relevant species in the Early Bird tree (see supporting information, file 1).” (Yuri et al. 2013: 424)

    Pteroclidae/Pterocleidae/Pteroclididae

    AFAIK, the first form is the one most frequently used in the literature.

    Link to this
  30. 30. John Harshman 4:56 pm 07/8/2013

    We do have explicit phylogenetic definitions of all the named clades (which should be PhyloCode kosher), but I see they didn’t make it into the final paper. There’s a short paper in preparation just for the definitions, though.

    Link to this
  31. 31. John Harshman 4:59 pm 07/8/2013

    I have always used “Metaves” and “Coronaves” in quotes like that to represent any group with slightly different composition from the ones Fain & Houde specified. Opisthocomus continues to wander freely all over the tree. Several other “metavians” aren’t much better.

    Link to this
  32. 32. Therizinosaurus 5:13 pm 07/8/2013

    David- Even if you are right that a genus “Australaves” would have to be emmended to “Australavis” according to the ICZN, there is still no inverse rule for clades like Australaves, so my point stands.

    But in any case, I read the ICZN differently than you (ambiguity in the code?! why I never…). While Article 26 would indeed have us assume “Australaves” is the foreign word “Southern birds”, Article 11.8 would allow us to treat “Australaves” as a noun in the nominative singular, even if it really isn’t. Further, I take Article 32.5.1 to mean that we can’t determine Australavis is an error. Ericson only uses that spelling, and does so on multiple occasions. He also named Afroaves in that same paper, so obviously knows how to form such names. It may have actually been an error of course, but we can’t know that just by looking at the paper. Article 30 is only about gender, so claiming it allows us to use knowledge of Greek and Latin to ascertain whether a spelling is a mistake in other ways is strictly incorrect (indeed, you could use this reasoning to claim Caudipteridae and such are evidentially erroneous). This is beginning to resemble the narrow vs. broad interpretations of the US Constitution… ;)

    Link to this
  33. 33. naishd 5:23 pm 07/8/2013

    For the record, I’m with John (comment # 31) on use of Metaves (though, granted, I didn’t use quotes above, nor am I doing so here). I don’t have any special confidence in the monophyly of a Metaves-type clade (contra comment # 12!), I’ve merely depicted the recovery of a clade that has approximately similar membership to Metaves as originally reported by Fain and Houde.

    Darren

    Link to this
  34. 34. David Marjanović 7:56 pm 07/8/2013

    @Troodon Man: Provided cats are herbivorous and superprecocial, sure.

    Calling troodontids “herbivorous” is probably an exaggeration; but it does look like they were more omnivorous than cats!

    “The supra-ordinal clades listed in Table 1 are defined as the least inclusive clade comprising the relevant species in the Early Bird tree (see supporting information, file 1).”

    Oh! Sorry! That should work. (I’ll be generous about the confusion of clades with their names.)

    At the risk of going off-topic, isn’t there rather robust support for the Atlantogenata hypothesis from post-2009 analyses?

    Do any of them talk about the retroposons?

    There’s a short paper in preparation just for the definitions, though.

    That’s good!

    there is still no inverse rule for clades like Australaves, so my point stands

    Indeed. I was just talking about your hypothetical example, not about your actual point.

    Also, I haven’t read that paper, but so far it seems to me like Australavis and Cantiomimus were sort of intended as genera: ranks are meaningless, and the PhyloCode doesn’t care about grammatical number either, so why not engage in grandiose lumping…

    While Article 26 would indeed have us assume “Australaves” is the foreign word “Southern birds”, Article 11.8 would allow us to treat “Australaves” as a noun in the nominative singular, even if it really isn’t.

    :-) I put it the other way around in comment 23: while Art. 11.8 makes it seem like anything goes, Art. 26 adds restrictions!

    Not the first time that the Code contradicts itself on issues that the Commission simply never imagined.

    Further, I take Article 32.5.1 to mean that we can’t determine Australavis is an error.

    As I wrote, if you read it with the implications of Art. 30.1 in mind, we can.

    indeed, you could use this reasoning to claim Caudipteridae and such are evidentially erroneous

    …Art. 11.7.1 actually says exactly that. Art. 29.4 says that “Caudipteryxidae” would be allowed if published after 1999, but Caudipteridae is invalid.

    Art. 29.5 does allow Caudipteridae, but only if it is in prevailing usage. It’s been in so little usage that I can’t imagine anything can be said to have prevailed at all! Amphiumidae is one thing, and so is Ceratopsidae as far as I can see, but Caudipteridae? Hardly.

    This is beginning to resemble the narrow vs. broad interpretations of the US Constitution… ;)

    *shoots you, a well-regulated militia(,) being necessary to the security of a free State*

    Link to this
  35. 35. Lars Dietz 7:34 am 07/9/2013

    Mayr’s definition for Aequornithes wouldn’t actually correspond to the “waterbirds” clade in the Kimball et al. (2013) 50-gene tree, as it would exclude penguins + procellariiforms and storks. So it would be a good idea to include at least a member of the former in the definition.
    On Galloanserae: Sibley & Ahlquist named it that way because they used standardized endings for each of their ranks (e. g. all suborders ended in -i, regardless of whether that was grammatically correct or not), and I think -ae was their ending for “parvclasses”. Rather like it’s done in some fossil invertebrates.
    Pteroclidae: I’ve seen all of the spellings mentioned by David, as well as Pterocletidae and I think some others. The etymology given by Temminck (1815) is: “Le nom générique Pterocles, que je propose pour ce genre, indique que ces oiseaux ont dans la forme des ailes, quelque chose de particulier”. I think the ending is the same as in Heracles, and as Heracles’ descendants were called Heracl(e)idae, I think either Pteroclidae or Pterocleidae is correct. I agree that the former is the most widely used.

    Link to this
  36. 36. Therizinosaurus 6:32 pm 07/9/2013

    “Also, I haven’t read that paper, but so far it seems to me like Australavis and Cantiomimus were sort of intended as genera: ranks are meaningless, and the PhyloCode doesn’t care about grammatical number either, so why not engage in grandiose lumping…”

    Well, it’s free here. If it were just Australavis, I’d be inclined to believe an editorial error was made, but Cantiomimus does seem to indicate a desire for obviously rank-free clades. Of course, someone could just email per.ericson@nrm.se and find out for sure…

    “Art. 29.5 does allow Caudipteridae, but only if it is in prevailing usage. It’s been in so little usage that I can’t imagine anything can be said to have prevailed at all!”

    On my website, I found “According to Google, Caudipteridae has 3550 search results compared to Caudipterygidae’s 685 (as of March 2010). Thus Caudipteridae should be maintained.” As of now, it’s 10900 vs. 2960, so Caudipteridae still wins.

    Link to this
  37. 37. CS Shelton 2:28 am 07/10/2013

    My partner was saying phylogeny is totally boring and useless to him. I don’t want to be judgmental of people with radically different interests from my own, but it seems sad to not have any appreciation for the beauty of all this. It’s so cool, seeing the interrelation of all terrestrial life. I never get tired of finding out new things about the tree. Or rooty tangled shrub, if that’s what we’re up to by now.

    Link to this
  38. 38. Chabier G. 6:40 am 07/10/2013

    I haven’t yet digested last phylogenetic avian trees, it’s very astonishing for me to see Cuckoos between Cranes and Bustards, for example. I find really exciting these relationships, challenging our “logical” perceptions inferred by morphological traits, and telling us about how evolution does work.
    One question, Does anybody trust in avian molecular clocks?, I think something is wrong, e.g., when splitting of early passerines giving origin to Acanthisittidae is dated more than 80 My ago, AFAIK, anything similar to a passerine has been found in Cretaceous strata.

    Link to this
  39. 39. David Marjanović 4:17 pm 07/10/2013

    There is no clock, and people have long stopped saying there is one. Calibrating divergence date analyses is difficult… difficult enough that I’ve got two publications out of it. :-]

    ICZN glossary entry for “prevailing usage”: “Of a name: that usage of the name which is adopted by at least a substantial majority of the most recent authors concerned with the relevant taxon, irrespective of how long ago their work was published.” Looks like this refers to valid publications, not ghits.

    Link to this
  40. 40. David Marjanović 6:38 am 07/13/2013

    *headdesk* Here, finally, goes Google Scholar:

    Caudipteridae: 6 results, 4 of which are papers.
    Caudipterygidae: 5 results, all of which seem to be papers or edited books.

    Link to this

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