At the Mic: Steve N.G. Howell
Steve is a senior international bird tour leader for WINGS and has written several books including A Guide to the Birds of Mexico and Northern Central America, Gulls of the Americas (with Jon Dunn), and most recently, Petrels, Shearwaters, and Albatrosses of North America. He lives near Point Reyes, California.
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There's no denying it: Molecular studies are helping us unravel the mysteries of avian relationships, and quickly. But until we fully understand the finer principles of genetics, the history of genes, and what that all entails, we will continue to make mistakes in our interpretations of the results of molecular studies. Is there anything we can do about this? Perhaps we can start with a grain of salt, and if that doesn't work then it's time to break out the lime and tequila.
A Tale of Two Orioles
As an example of the tribulations involved in molecular studies, let's review some recent developments with a time-honored favorite in the North American taxonomic arena - the Northern Oriole complex. The taxonomic tale of Baltimore Oriole Icterus galbula and Bullock's Oriole I. bullocki is fairly well known - two species, then one, and now three (what, three?). Less well known to most ABA members, perhaps, is the Mexican cousin of Baltimore and Bullock's - Abeille's Oriole I. abeillei (unhelpfully named Black-backed Oriole by those seemingly unaware that 12 of 16 oriole species in Mexico have black backs, including both Baltimore and Bullock's).
In 1999, a molecular phylogeny of New World orioles was produced, in which, supposedly, Baltimore Oriole and Abeille's Oriole were closely related, while Bullock's Oriole was more closely related to Streak-backed Oriole I. pustulatus (Omland et al. 1999, Molecular Phylogenetics and Evolution 12:224-239).
The authors realized how odd this looked, so a fuller genetic analysis was undertaken, which confirmed the earlier result (Kondo et al. 2004, Condor 106:674-680); it was then postulated that this was an amazing example of adult male plumage patterns diverging very quickly in an evolutionary time scale (between Baltimore and Abeille's). A follow-up paper by the same team (Kondo et al. 2008, Evolution 62-5:1182-1191) went on to show that Abeille's Oriole was derived from Baltimore Oriole (Bullock's Oriole was ignored). This was thus a remarkable case of a tropical resident species evolving from a migratory ancestor, contrary to the paradigm of resident tropical avifaunas tending to be the reservoir from which migration flows. Another paper used the new and "robust phylogeny" to explore the evolutionary history of plumage patterns in orioles (Omland & Lanyon 2000, Evolution 54:2119-2133). Another paper using the new phylogeny postulated that orioles colonized mainland South America from Caribbean islands (Sturge et al. 2009, Condor 111:575-579). And so on.
Amazing stuff. But this is where the trail of genetic clues led, so how could it not be true? Hence, the AOU (2000, Auk 117:847-858) moved Bullock's Oriole to follow Streak-backed Oriole, and thus separated it from Baltimore Oriole by five other species. Whiskey Tango Foxtrot was the response of many field ornithologists, but what did they know of genetics?
However, as knowledge of genetics increased, further molecular analyses of these orioles showed that the earlier grouping of Baltimore and Abeille's was in error (Jacobsen et al. 2010, Molecular Phylogenetics and Evolution 56:419-427; Jacobsen & Omland 2010, Ecology & Evolution 2:2413-2429). Today it is believed that Abeille's is more closely related to Bullock's Oriole, which fits with older conclusions based on morphology, vocalizations, and biogeography. These two orioles are a good example of how messy the progress has been in applying new genetic tools to avian taxonomy, for only a few years ago these two were "among the most closely related of avian species" (Kondo et al. 2008:1183).
Along with a clearer understanding of "Northern Oriole" relationships, the claims of rapid plumage evolution and of a resident tropical species deriving from a northern migrant are also now debunked. And given that the baseline phylogeny was flawed to an unknown degree, is it still true (as claimed by Omland & Lanyon 2000:2119) that "plumage patterns and colors are highly labile between species of orioles?"
Still, after a litany of at least five publications it would appear that we have established something more firmly than before, and hopefully we have a better understanding of the evolutionary history of these three species. But these three species of orioles live in North America, where many people were familiar enough with the birds to notice that the genetic results were incongruous with intuition. For the other species, less familiar to most people, the original results of Omland et al. (1999) appear not to have been questioned. My opinion is that most of their results look reasonable, yet it is entirely possible that some of the other relationships "proven" by genetics and statistics are in error. For example, Orange Oriole I. auratus and Streak-backed Oriole might be closer than reported. Either way, the unfortunate error involving Baltimore Oriole and friends does not instill confidence. Moreover, some well-marked, potentially species-level taxa were omitted from the analysis, despite "the importance of dense taxon sampling" in the title of Omland et al. (1999); an example would be Dickey's Oriole I. [graduacauda] dickeyae of west Mexico.
These molecular studies on relatively well-sampled orioles exemplify how little scientists really understand/understood about genetics. And these flaws went on to color or discolor a number of ecological and environmental studies and theories. Some might cry: "But that was then, this is now; today we really do understand things." Certainly one would like to think that our knowledge of genetics has improved in the past few years, but how much?
What Do We Not Know?
Although some may claim otherwise, avian geneticists are still groping around in a recently tilled but dimly lit field, learning how to use their new tools. Thus it seems only common sense to treat their early harvests as working hypotheses, especially at the taxonomic levels of genus and species. This is particularly true given that ornithologists can't even agree on what constitutes a species. In this regard, check out the eloquent but sobering essay entitled "A species is whatever I say it is" by Nigel Collar in the March 2013 issue of British Birds (vol. 106:130-142), which highlights numerous other examples of the unresolved issues with genetic studies.
Although problems with genetic analyses may be fewer than those associated with studies based on non-genetic data, they are still problems. Despite this, taxonomic committees appear to have fallen in love with "glamorous" DNA studies, seduced by the promise of ultimate truth. Hence it often seems they are running amok on freshly plowed soil of uncertain viscosity, undervaluing or ignoring non-genetic tools that might help them avoid getting needlessly stuck. One day, who knows, the genetic tools may be so refined that we won't need any other lines of evidence, but there will be years or decades of messiness before we reach that point - if we ever do.
In the meantime, species and genera are constantly being shifted around hither and thither. Bullock's Oriole is only the tip of the iceberg. Of course, birders only "suffer" from all this if they try to keep up with lists that are changing every week, or with using field guides compelled to adopt the latest and greatest changes - regardless of whether these changes are helpful for somebody trying to identify a bird. I can only think that poor Roger Tory Peterson must be rolling in his grave, now that the new Peterson field guides to birds try to follow taxonomic sequence - which is contrary to the simple brilliance of Peterson's original system.
One cannot help but wonder how many more taxonomic decisions fueled or driven solely by genetics are simply errors in analyses. The merger of skuas into the genus Stercorarius, because Pomarine Jaeger is supposedly more closely related to Great Skua than to the other jaegers? Putting Willet in between Lesser Yellowlegs and Greater Yellowlegs? Are all the recent wood-warbler genus reshuffles truly accurate, or might some be changed again? And how about them sparrows and towhees? And so on... How many things do we not know that we don't know?
Thanks to Ned Brinkley, Burr Heneman, Alvaro Jaramillo, Peter Pyle, and Brian Sullivan for comments on an earlier version of this essay.
P.S. As of March 2013, the AOU check-list still separates Bullock's Oriole from Baltimore Oriole by 5 species of orioles: Orange, Jamaican I. leucopteryx, Spot-breasted I. pectoralis, Altamira I. gularis, and Audubon's I. graduacauda. Yet Yellow-backed Oriole I. chrysater is 9 species distant from Audubon's, despite the phylogeny of Omland et al. (1999), which placed Yellow-backed and Audubon's as each other's closest relatives (a view that is supported by morphology, voice, and biogeography, pending analysis of the unsampled taxon dickeyae, mentioned earlier). Time to pass the tequila...
Genbank sequences can compound the problem, when they are not accompanied by properly vouchered specimens. Molecular systematics can become meaningless if totally divorced from morphological systematics.
Posted by: J.J. Schmitter-Soto (@jjschmittersoto) | 04/10/2013 at 11:12 AM
Steve Howell mentions the Nigel Collar essay, "A Species Is Whatever I Say It Is." Here's another essay, from the perspective of an expert who is not an ornithologist:
http://tinyurl.com/Get-Rid-Of-Species
I think it's safe to say that many birders aren't aware of just how quaint ornithological species concepts are to the many excellent biologists working in such fields as horticulture and entomology.
In an upcoming essay in the print version of Birding magazine, Steve Howell writes:
"...the intention in much of my writing is simply to encourage the many people who use bird checklists to think for themselves; to actively engage and question the various committees that pass judgment; and even sometimes to question the primary literature on which decisions are based."
I disagree with some of what Steve Howell writes about, but I sure agree with the sentiment above. Question authority. Question the conventional wisdom. Question received "knowledge."
The species concept is a powerful and seductive construct, no question about it. But is it real? Is it useful? Does it advance our understanding of how the natural world really works?
As Steve Howell probably would say: Think about it.
Posted by: Ted Floyd | 04/10/2013 at 02:57 PM
Of course, any phylogenetic study (molecular or morphological) should be examined with a critical eye (not just papers on evolutionary relationships).
Like any new field, much of the early work was done at a time when sequencing was new enough that it was expensive and many of the major pitfalls had yet been discovered. So I am kind of surprised, despite the name of the article, little actual information is given on why the results of the above analyses were flawed, or how you should actually evaluate new data. Instead, the author takes a position that is essentially argumentum ad populum. That you should ignore scientific evidence and go what your "gut tells you". That
Omland et al. 1999, the first of the oriole papers, only used 2 partial mitochondrial genes. Kondo et al 2004 also only used 2 mitochondrial genes. While mitochondrial DNA is useful, it is only passed maternally and so might not reveal the full story. Similarly, there are many cases where using single genes have led to different reconstructed trees than the actual evolutionary tree.
To counteract this, researchers typically employ both mitochondrial and nuclear DNA, which are inherited differently. the more genes and the more sources of information you can employ to generate a tree (including morphology, which is my primary area of interest), the stronger your conclusions will be. Other things to watch out for are methods of analysis (Bayesian and Maximum likelihood are way better than parsimony or neighbor-joining methods) as well as sampling and sample size. AOU itself is aware of this, and typically has avoided major revisions of groups based on single gene sets.
When he encourages people to look to there gut, I can only think of my own field. Since I have been working with marine mammals, we have seen some major changes in how we view their evolutionary relationships. Molecular evidence was the first to establish whales as even-toed hoof mammals, which was summarily dismissed...until we kept getting that result, and until scientists started finding early whales with distinctive hoofed mammal leg bones. Pygmy Right whales were found to be closer to gray and rorqual whales, something that seemed ludicrous due to there resemblance to right whales. Until again, more careful appraisal of morphology of living and fossil whales has proven that they are indeed not closely related to right whales.
As for reshuffling of taxa...yes this should be conservative (although Steve Howell has argued elsewhere that AOU is TOO conservative when it comes to defining species). Which is what I think we have been seeing with in recent years. But we also shouldn't hold off on making any changes until some magical day when genetics is understood to the satisfaction of Mr. Howell. Nor does the AOU checklist committee serve the whims of birders...the checklist is meant to be an accurate reflection of bird taxonomy as known at the present.
Finally...I will just end with saying that the AOU checklist committee accepts taxonomic proposals from the public as well as other scientists. If the oriole problem needs to be addressed, anyone with an interest can take the time and submit a proposal.
Posted by: Morgan Churchill | 04/10/2013 at 03:32 PM
What is the distinction between a hypothesis and a "working hypothesis"? Aren't all hypotheses simply works in progress subject to revision when new or contradictory data comes to light?
Posted by: Chas Swift | 04/10/2013 at 04:23 PM
I think some birders would be surprised to learn that Downy and Hairy Woodpeckers are not closely related; Downy being allied with Nuttall's, Ladder-backed, and the palearctic Lesser Spotted Woodpecker, and Hairy being allied with White-headed, Arizona, and Red-cockaded Woodpeckers. So the Downy-Hairy similarity appears to be a case of plumage aspect convergence. As is the case with some of the wood warbler changes, this demonstrates how structural morphology i.e. size and shape (or "giss") can be pretty phylogenetically informative.
Posted by: William Rockey | 04/10/2013 at 06:00 PM
From a conservation standpoint, nailing something down as a species, a subspecies, or an evolutionarily significant unit is critical.
How many times have populations and their habitats been lost because there wasn't enough scientific consensus or political impetus to say, "Yes, this is an important taxon and it should be conserved through legal and political channels?"
Even if the taxonomists are wondering how many angels can dance on the head of a pin, most of us need to be able to call a Preble's meadow jumping mouse a Preble's meadow jumping mouse, and work to conserve the habitat accordingly.
Posted by: Brooke | 04/10/2013 at 07:33 PM
"Putting Willet in between Lesser Yellowlegs and Greater Yellowlegs?"
As Paul Hess writes in the current (March/April 2013) issue of Birding, this result recently has been independently confirmed. So it looks good. But that's not my point. My point is this:
When we get new genetic data--falcons are closer to parrots than to hawks, grebes are close to flamingos, longspurs aren't sparrows, ducks and grouse are close to each other, vireos are closer to crows and shrikes than to warblers and thrushes--let's ask ourselves: What do those things say about our earlier assumptions and biases?
I'm with Theodosius Dobzhansky (1900-1975) on this one: "Nothing in Biology Makes Sense Except in the Light of Evolution." If we think that the yellowlegs are similar, but modern evolutionary studies tell us they're not all that similar, then the problem is with us, not with reality. The problem is that we've been making faulty inferences all along. I love going out and watching birds, and saying to myself and to others:
"Look at that flock of longspurs. Their flight calls are so different from sparrow flight calls. The way they flock is more lark-like than sparrow-like. What about their plumages and molts?--y'know, now that I think about it, they're not all that sparrow-like. Isn't it strange that I used to think they're a kind of sparrow?"
"Oh, cool. A kestrel and a Sharpie in the air at the same time. Let's try to focus on all the differences. Evolution tells us that the kestrel is part of a falcon-parrot-passerine clade, but the Sharpie is in a big group that contains everything from herons to penguins. Let's use evolution to make us better at separating small falcons from small accipiters."
"Look, there's a Western Willet out there with that flock of Lesser and Greater yellowlegs. Despite our earlier biases and assumptions, we now know that the Greater Yellowlegs is more closely related to the Willet than it is to the Lesser Yellowlegs. How come the Willet diverged, at least in terms of plumage, rather quickly from the common ancestor, whereas the Greater Yellowlegs has diverged more slowly?"
One more:
In the upcoming May/June 2013 Birding Paul Hess reports the cool result that the American White Pelican's closest relative is the Brown Pelican--not, as you might think, the other white pelicans of the Old World. That's fascinating. It means we get to ask exciting questions like: "Why did an ancestral colonizer in the New World diverge slowly into the American White Pelican (plumage and behavior similar to the Old World white pelicans), whereas the Brown Pelican complex diverged quickly?"
To me, the great lesson of the Enlightenment is that we humans do a pretty crappy job of discerning how the universe really works: The Earth revolves around the Sun; space and time are relative; the Earth has been around for billions of years; life on Earth evolves; longspurs aren't sparrows; falcons aren't closely related to hawks; and the Greater Yellowlegs is more like the Willet than it is like the Lesser Yellowlegs--despite all our pre-Enlightenment biases and assumptions about the way things oughtta be.
Thanks to Steve Howell for provoking us, as he so often does, to reconsider our worldviews.
Posted by: Ted Floyd | 04/10/2013 at 09:19 PM
"Even if the taxonomists are wondering how many angels can dance on the head of a pin, most of us need to be able to call a Preble's meadow jumping mouse a Preble's meadow jumping mouse, and work to conserve the habitat accordingly."
I'm fine with calling it a Preble's meadow jumping mouse. I just don't see the value in calling it a species. Or subspecies. Or whatever.
Let's work to conserve the Preble's meadow jumping mouse; let's not worry about "nailing something down as a species..." That's just angels dancing on the head of a pin.
Posted by: Ted Floyd | 04/10/2013 at 10:20 PM
I would suggest that the problem wasn't that we or anyone was making faulty inferences. It was that we had insufficient information. It is a great advantage in constructing clades to have genetic studies available. I don't think we should accuse earlier scientists of having 'bias' or making 'assumptions'. I would suggest they were making the best interpretations possible using the information that was available to them. If all you have are morphological studies, I can see how it would seem like the best interpretation of the data to put Greater and Lesser Yellowlegs together. Certainly, some of them may have interpreted things mistakenly. That's just part of science. As we get more information, we make better interpretations. Perhaps they could have done a better job analyzing the data than they did. Well, at the end of the day, I think if we are honest, we all have to admit to that - at least sometimes.
Certainly, there are scientists who cling to outworn theories when they have outlived their usefulness and have been sufficiently shown to be false. They are an impediment to the advance of knowledge, but I like to think that most scientists and hopefully most birders are not like that. Perhaps I am wrong in my optimism.
Posted by: James Swanson | 04/11/2013 at 09:33 AM
In response to the comments to date: thanks to all for posting and thinking about this question. More specifically:
While one might argue that the term "working hypothesis" distinguishes such a hypothesis from one that isn't working, I thank Chas Swift for drawing attention to this redundancy. Oops!
I have seen comments on other ABA blog posts where people like Morgan Churchill ascribe words to writers or misrepresent sentiments, yet the writers in question never wrote what was being claimed. Mr. Churchill apparently (by his own admission) is a scientist, yet his inability to read and understand what I wrote would better qualify him for the field of popular journalism.
He wrote: "Instead, the author takes a position that is essentially argumentum ad populum. That you should ignore scientific evidence and go what [sic = with what?] your "gut tells you"." His use of quotation marks implies he is quoting something I wrote (which he is not), and his use of Latin indicates a predisposition to academic pomp, in which one is unable to communicate in clear English. He also wrote later of me: "When he encourages people to look to there [sic = their] gut, ..." Perhaps he could point out where I said that, rather than projecting his own interpretation into the arena.
Nowhere did I write that we should ignore scientific evidence, but rather I suggest that the molecular science involved might be more rigorous (or at least the analyses might be), laced with a modicum of common sense, and sometimes viewed with a degree of skepticism. Indeed, I opened by acknowledging that molecular studies are helping us to better understand avian relationships, and I find this all fascinating and intellectually stimulating. But the dance won't be over until the music stops, and I am unconvinced that today, when it comes to species-level and even genus-level taxonomy, we have little more than a vague idea of the molecular beat. Basically, if Nature were simple enough for us to understand, we would be too simple to understand it.
(As an aside, I am surprised that Mr. Churchill writes: "Pygmy Right whales were found to be closer to gray and rorqual whales, something that seemed ludicrous due to there [sic = their] resemblance to right whales." Anyone who has seen a Pygmy Right Whale in life, or even looked at an illustration in a field guide, would be hard pressed to divine more than a passing resemblance to a Right Whale, and likely would not be in the least bit surprised by this finding.)
William Rockey's comment on woodpecker relationships would benefit from a reference, so that readers could evaluate the source of his statement. His claim may be well founded, but without access to the data it also might be said to sound suspiciously like what somebody would have confidently written only a few years ago: "Baltimore Oriole is more closely related to Abeille's Oriole than it is to Bullock's."
Posted by: Steve Howell | 04/11/2013 at 03:03 PM
Ted Floyd's examples suggest he buys completely into the genetic studies that "prove" the relationships he discusses. Likely it is all correct, but do we know for sure? We should remember that multiple data sets can corroborate things, but not always.
As an example. Some of you may remember a few years ago when New World Vultures were shifted next to storks, and away from hawks. This was supported by morphological, behavioral, and molecular studies - multiple data sets from different directions.
And then we all said (and I include myself here): "Oh yes, I can see that now, vultures really are just modified storks, how cool is that, it is really pretty obvious, in hindsight... " And then, apparently, the evidence has been reconsidered, and now vultures are back next to hawks and are not, supposedly, closely related to storks. Perhaps next week they will be found to be closer to storks, who knows? This is just the way science works. We have all been fooled by superficial resemblances, by convergent evolution, and molecular studies have the potential to help us sort through that confusion.
My point, however, which is more philosophical than biological or scientific, is that anyone should feel free to wonder if we have jumped too quickly on to the wrong bandwagon. The short history of genetics is full of examples of good science, and also of errors, most inadvertent. Change is inevitable. Today, however, the sheer speed of change is what is new, and I think we could all benefit from slowing down a bit, and from not having to change our checklists every month, every week, every hour, only to find we need to change them back again next week. It may be "science" but it sure is an inefficient use of everyone's time.
An example? We now live in an age when journal editor's wrongly "correct" the taxonomy and scientific names in papers that have been submitted, because they themselves are not up to date on the latest AOU taxonomy; that should be a sign that things are becoming unmanageable. We are only human, after all (at least, last time anyone checked the genetics...).
Posted by: Steve Howell | 04/11/2013 at 03:22 PM
Random points:
I used "quotes" not because I was directly quoting you, but because I was using a more colloquial terminology. I used latin because that was simply the proper way of phrasing for that particular style of argument.
It's pure mincing of words when you complain about me misquoting you and saying you never said what I implied, when you write "many people were familiar enough with the birds to notice that the genetic results were incongruous with intuition" does not translate to "intuition is better than data", and that intuition is what your gut tells you.
By all means question data and new hypotheses. And yes I would prefer taxonomic changes to be somewhat conservative and only made when strong support is found in multiple studies (although I suspect our definitions of strong support are not the same). But please try to use arguments more persuasive than "intuition" when railing against changes.
P.S. regarding the pygmy versus regular right whale, please keep in mind that prior to a couple of years ago, every single morphological study and taxonomy, including many very large and rigorous analyses, had found a close similarity between right whales and pygmy right whales, mostly relating of features of the cranium. really the only obvious differences based on casually examining them is color, absence of callosities (which is a derived trait in modern right whales) and presence of a dorsal fin (which could be ancestral retention). They are also smaller, but there are plenty of small right whales in the fossil record who have skulls nearly identical to the modern species.
Posted by: Morgan Churchill | 04/11/2013 at 04:20 PM
I think "intuition" as Steve used it implies being more informed than "what your gut tells you" seems to. He was hardly "railing against changes." Taxonomy is an inexact science. Conclusions are always changing, based on what specific morphological, physiological, behavioral, acoustic, and genetic data one is drawing those conclusions on. The AOU has kept up with new ideas in taxonomy, but producing a new Checklist every single year can seem counter-productive, especially since DNA-based taxonomy is developing so rapidly. It's important for those of us interested in taxonomy to keep up with current assessments of whether, say, vultures are more closely allied with storks or with diurnal raptors. But to constrain complex and on-going research into absolutes in checklist form every year, even as other researchers are reaching different conclusions, seems counter-productive.
I've attended a few ornithological meetings, but I've shied away from taxonomy sessions since the first meeting I went to. After one scientist presented his paper, another taxonomist said during the Q&A, "You must have put that together during that messy divorce. You clearly were not thinking straight." When different scientists, using different kinds of data, reach different conclusions, emotions and ad hominems start taking over reasoned discussion. I hope that doesn't happen here.
Posted by: Laura Erickson | 04/11/2013 at 04:56 PM
Here's a paper by Weibel and Moore 2005 highlighting these Picoides findings:
http://bio.wayne.edu/profhtml/moore/PUBLICATIONS/Weibel&Moore2005Condor.pdf
Two other papers of theirs from 2002:
http://bio.wayne.edu/profhtml/moore/PUBLICATIONS/Weibel&Moore2002a.pdf
http://bio.wayne.edu/profhtml/moore/PUBLICATIONS/Weibel&Moore2002b.pdf
Posted by: William Rockey | 04/11/2013 at 05:08 PM
Morgan said: "Nor does the AOU checklist committee serve the whims of birders...the checklist is meant to be an accurate reflection of bird taxonomy as known at the present."
I agree wholeheartedly with this (and the fact that phylogenetics is getting much better, which Morgan also mentions) and think this article was more than a little overblown.
Yes, science is an ever-changing process as techniques get refines, theory gets debunked and views shift. Should we, as the author insinuates, basically give up on phylogenetic tools (and science in general?)?
"One cannot help but wonder how many more taxonomic decisions fueled or driven solely by genetics are simply errors in analyses.... How many things do we not know that we don't know?"
1) Not only phylogenies and molecular tools suffer these sorts of problems, as Morgan alluded to.
2) Perhaps I am just cranky, but I'd take the best known (at the current time) scientific cure for any ailment I have or solution to a problem. That is not absolutely the best one, but its the best we've got now. Obviously take everything with a healthy bit of skepticism, but don't outright reject it just because some technique (15 years ago) was wrong.
And a small rant: a common problem, which I cannot tell if the author is having here or not (but last paragraph seems like they are), is that order of the species in a list (representing the tips of a phylogeny) does not show accurately their relatedness as any node can be reversed without changing relatedness.
Posted by: Eric | 04/11/2013 at 05:51 PM
Ted, you say you're fine with calling it a Preble's Meadow Jumping Mouse, but at the very least you'd need to define a community of mice with some common characteristics, with either some geographic or genetic or morphological distinction from other mice. You really haven't solved a problem by getting rid of the species or subspecies concept. Nothing in science is ever completely precise, look at Newton's laws of physics, and look at Einsteins laws of physics... they are both inaccurate at some fine level of detail, but they work at other levels. You can't just throw them both out wholesale because they don't work at the quantum level.
Posted by: Paul | 04/11/2013 at 06:06 PM
I'm not a biologist. I'm just a nature lover, native plant enthusiast and a birder. I look forward to the AOU changes. I think they're fun. I love changes in science, what's wrong with change?
Posted by: Paul | 04/11/2013 at 06:40 PM
Absolutely nothing is wrong with change. But publishing an updated AOU Checklist every single year seems arbitrary, especially at at time when so many changes are so quickly reversed, such as where the vultures are placed.
Posted by: Laura Erickson | 04/11/2013 at 06:52 PM
Does that mean I have to wait even longer for a Fox Sparrow split? ;-) Just kidding, I take it all with a grain of salt, but I do enjoy the yearly AOU changes, whatever they may be, and the tequila... actually, just kidding about that too.
Posted by: Paul | 04/11/2013 at 07:17 PM
I simply listed the species as the AOU lists them, which does not agree with the sequences of the oriole phylogeny, regardless of the seemingly arbitrary sequence in which species at the tips of branches can be listed, or which node takes precedence. Perhaps Eric or Morgan can clarify what if any scientific or taxonomic principle governs the sequence in which species are listed in linear sequence, when there can be several equally valid (?) alternatives. I am not a taxonomist, and have often wondered whether some rule governs this, or whether it is simply arbitrary and up to the whim of the authors of a given paper; the latter approach does not seem particularly scientific, so I suspect there is a rule and would appreciate learning what it is.
Posted by: Steve Howell | 04/11/2013 at 08:57 PM
In theory it follows Linnean classification and the branching order of the tree. In practice a tree is hard to convert to a list of species, not everything can be kept equally up to date, and we don't have a good understanding of what goes on for some parts of the tree.
Although I honestly don't believe there is a better way of presenting a taxonomic list, since the whole purpose of a taxonomy is classification
FYI I don't believe that a field guide or refuge checklist has to follow that order. I (personally) like that order, but can see how other systems would also work for people with other interests
Posted by: Morgan Churchill | 04/11/2013 at 09:15 PM
"I'm not a taxonomist, but I play one on TV" is what came to mind when Steve mentioned he was not a taxonomist. I think a taxonomist is one who does taxonomy, and for years Steve you have been doing this, in your field guides and books and scientific papers dealing with the relationships of birds. So out of all of the stuff I read above, this is the part that stuck out. You do taxonomy Steve, doesn't that make you a taxonomist? Maybe not a professionally funded one? Like it or not you are one of "THEM" :-) Saludos and enjoy the tequila.
Posted by: Alvaro Jaramillo | 04/12/2013 at 04:36 PM
My query related to a branch that has, say, a 3-way fork, all subsequent sub-branches seemingly equal in length - in what order does one list the 3 species at the tips? When you say Linnaean, does that mean the taxon described first (by Linnaeus or anyone since) is listed first, regardless of whether it evolved first (which we may never be able to divine)? Or is it just, as it seems, arbitrary?
Posted by: Steve Howell | 04/13/2013 at 06:46 PM
"I am not a taxonomist, and have often wondered whether some rule governs this, or whether it is simply arbitrary and up to the whim of the authors of a given paper; the latter approach does not seem particularly scientific, so I suspect there is a rule and would appreciate learning what it is."
While it sounds sort of odd, I think it is the latter. Think of a three species tree, A is the base and B + C are sister species. You could present it as A B C or A C B, each are equally correct if B and C are still most closely related to each other (i.e. you just rotated the node). I suspect that since phylogeneticists know this, there is no convention, since they can interpret these correctly when looking at the phylogeny. I do not study phylogenetics, but I find the easiest way for me to internalize how different species are is to count the nodes between them. The closest species will have 1 and everything else from there is farther. Obviously this disregards branch lengths and each node we see now may be one of 100s which existed in the past but it gives you a pretty quick and dirty approximation (which is all I need!).
Posted by: Eric | 04/23/2013 at 11:40 AM