Aves mexicanus

BY: Bob Montgomerie, Queen’s University | 1 May 2019

One of the curious traits shared by birders and professional ornithologists is an abiding interest in bird names, both common and scientific. With respect to common (English) names, I have previously highlighted attempts at standardization in the 1830s (here), one recognizing a woman (here), one that is obscure and obsolete (here), a recent name change (here), and an odd misnomer (here). Since 1850 dozens of books and papers have been published about the English and Latin names of birds (see list here). And a new book by Stephen Moss Mrs Moreau’s Warbler provides some delightful insights into the origins of many odd common names.

The scientific names of birds have attracted less interest, in part, I assume, because those names are regulated by the International Code of Zoological Nomenclature (ICZN). The ICZN governs the designation of type specimens, the choice of scientific names and the rules of priority.  The code’s Principle of Priority mandates that taxon names (species, genus, family, etc) are always the ones that appeared first in print. All of these taxon names can only change when taxa are lumped or split but the rule still applies to newly designated taxa. Hugh Strickland proposed that first rule in his 1842 report to the British Association that established the ICZN. Thus scientific names are not really open for discussion or change unless a mistake has been made.

Quite a few of the scientific (Latin) species names of birds come from country names. This is largely due to European explorers collecting and describing a species for the first time and naming the species after the country where the first specimen was collected. According to the current IOC World List [1], australis is the most common species epithet that looks like a country name, used for 22 extant bird species in 22 different genera (by necessity) and 10 orders of birds. But australis means ‘southern’, and not ‘Australia’, and only 8 of those species occur in Australia, the rest being found in New Zealand (3), Africa (6), south Pacific (3). south Atlantic (1), and the USA (1).

Thus the most popular country name used for species is americanus/americana with 17 extant species but here again the authors were often referring to the Americas and not specifically to the USA or even North America. I have not checked to see where the type specimens were collected but 4 of those species do not occur in the USA and 2 do not occur in North America.

Species unequivocally named after a country include indicus (17), mexicanus (14), peruvianus/peruanus (12), canadensis (8), sinica/sinensis (7), brasiliensis/brasilianus (6), portoricensis (4), and  colombianus/colombica (3) [2]. Species named after a continent include africanus/africanoides (11) and asiaticus (7). Interestingly, few species were named after European regions where those very explorers came from:  euopaeus (2), germana (1), scotica (1), brit- (0), espan- (0), ital- (0), norv- (0), and sver- (0)..

All of the species named indicus appear to occur in India, but 3 of the species named mexicanus are not really Mexican [3], and two do not even occur in Mexico—the Puerto Rican Tody (Todus mexicanus) being endemic, not surprisingly, to Puerto Rico, and the Oriole Blackbird (Gymnomystax mexicanus) which lives in northern South America.

Birds with species name mexicanus

About a month ago, Tom Sherry (Tulane University) wrote to ask if I knew anything about the history of the species name mexicanus for the Puerto Rican Tody. I didn’t, but his query prompted this post. It has taken me a couple of weeks to explore this question and it has so absorbed me that I had no time to post anything [4] on the past two Mondays as I usually do.

The scientific name of the Puerto Rican Tody dates from 1838 when the bird was described (see below) by René Primevère Lesson in a paper he wrote about some todies new to science. Lesson called the species Le Todier vert, rose et bleue and noted that it was from Puerto Rico (L’île Porto-Rico). His footnote #2 says that this is Todus portoricensis and attributed this name to Adolphe Lesson, his brother (who was a botanist). His footnote #1 refers to the previous species (probably the Jamaican Tody) on that page Le Todier vert et jaune that he calls Todus viridis or Todus mexicanus, also discovered and reported by his brother Adolphe, from Veracruz in Mexico.

First description of Puerto Rican Tody (Lesson 1838)

Now, I am by no means an expert on the rules of nomenclature but it seems to me that it is a mistake to call the Puerto Rican Tody Todus mexicanus, and that Todus portoricensis is both correct and appropriate. Dr Sherry tells me that some birders that he met on his trip to Puerto Rico wondered how the apparently mistaken scientific name came to be. Maybe it is a real mistake and there would be a case to have the scientific name changed. By any name, this is a beautiful little bird.

Puerto Rican Tody (Kevin Loughlin PHOTO)


  • Lesson RP (1838) Mémoire descriptif d’espèces ou de genres d’oiseaux nouveaux ou imparfaitement décrits. Annales des Sciences Naturelles 2(9): 166-176
  • Moss S (2019) Mrs Moreau’s Warbler: How Birds Got Their Names. New York: Faber & Faber.


  1. IOC World List: I used v 9.1 available here
  2. country or continent names: the names listed here include feminine and neutral variants (e.g. both asiaticus and asiatica). I have listed all the names that I could find that had >2 examples.
  3. not really Mexican: the Prairie Falcon (Falco mexicanus) breeds and winters in northern Mexico but 9/10 of its range is in the USA
  4. no time to post anything: not to mention attending the funerals of two colleagues, marking 48 final term papers in my history and philosophy of biology course, and trying to meet the Canadian income tax deadline

IMAGES: mexicanus species from Handbook of Birds of the World online; excerpt from Lesson’s paper from Biodiversity Heritage Library; Tody photo courtesy Kevin Loughlin (via Tom Sherry)

The Story of O(ology)

BY: Bob Montgomerie, Queen’s University | 15 April 2019

After a seminar last week, my colleague Jannice Friedman, a botanist, asked me if ‘oology’ was really a word, as it had appeared on one of the speaker’s slides. So, she asked, what is the ‘o’ that ‘ology’ (the study of) has been tacked on to? I explained to her that oology (or oölogy) is the study of eggs, and birds’ eggs in particular, but I had no idea why it was not something more logical like ‘ovology’ [1]. Oology is one of those words like ‘popsicle’ and ‘’castle’ that are familiar but then sound ridiculous when you think about them or repeat them too often [2].

W. C. Hewitson

The OED says that oology first appeared in print in English in 1830, in an advertisement [3] for the soon-to-be-published British Oology by William Hewitson. Hewitson published this ‘book’ as a series of fascicles, sold by subscription beginning in 1831 and completed in 1838. The second (1843-44) and third editions (1856) were called Coloured Illustrations of the Eggs of British Birds. Among the subscribers to that first edition were such notables as John James Audubon, John Gould, W. J. Hooker, Sir William Jardine, Prideaux John Selby, and William Yarrell [4]. It was clearly a popular publication on a popular topic.

Hewitson’s British Oology starts with an Introduction in which he waxes poetic about his love of Nature, and the pleasures of egg-collecting: “who does not remember those joyous times when, at the first breaking loose from school, he has hied him to the wood and the hedge-row, in search of his painted prize?”[5] In that first edition, he describes the eggs and nests of 229 species that bred in Britain, illustrated with coloured plates that he drew on lithographic stone and then hand-coloured. Those plates, curiously, show no more than four eggs per page, all life size, and thus the plates are often mostly white space (see below).

Some of the eggs shown in British Oology

Like most pre-Darwinian naturalists, Hewitson saw in the design of eggs some God-given purpose for the good of mankind: “For the same purpose for which they adorn the plumes of the Humming-bird, or the wing of the resplendent butterfly — to gladden our eyes, ‘To minister delight to man, to beautify the earth.’ And thus it is that the eggs of nearly all those birds (the Owl, Kingfisher, Bee-cater, Holler, Nuthatch, and the Woodpeckers) which conceal them in holes, are white, because in such situations colour would be displayed to no purpose.” [5].

Even in the interspecific variation in clutch size, Hewitson saw the hand of God providing for mankind: “In every instance we shall find the same beneficent influence acting for our welfare; increasing rapidly, by the number of their eggs, those species which are of the greatest use to us, and bestowing upon those intended for our more immediate benefit, a most wonderful power of ovo-production; and at the same time curtailing in their numbers those species which, in their greater increase would soon become injurious to us.” [5]

Despite all of that teleology, Hewitson was perceptive in noting that species with precocial offspring have eggs that are larger relative to female size compared to species with altricial hatchlings. He also concludes that egg colour cannot be generally useful for camouflage except in a few ground-nesting birds. With respect to the use of eggs in taxonomy, he has a mixed message but still seems to want to cling to the idea that egg traits will be useful for classification [6]. His descriptions of breeding habitats, nest construction, breeding seasons and clutch sizes provide a useful window on the state of knowledge about British birds almost two centuries ago.

I assume that the word ‘oology’ was already in general use when Hewitson published British Oology because he uses the term without definition or special mention, as if all readers would know what he was talking about. For the next century oology was a prominent topic among people interested in birds, the subject of several books, myriad papers, and even a museum of oology [7] in Santa Barbara, California. Hewitson later turned his attention to collecting and illustrating lepidoptera, but occasionally dabbled in oology, mainly updating his British Oology with papers on new discoveries in the British Isles and continental Europe.

So where did that word ‘oology’ come from? The OED says that it is a combination of ‘oo’ and ‘logy’ but that really does not make sense to me as ‘ology’— not ‘logy’—is the standard suffix meaning ‘the scientific study of’. For example, Wikipedia lists 342 ‘ologies’ all of which appear to append ‘ology’ onto a subject of study: bi-ology, ichthy-ology, ornith-ology. The OED also says that ‘oologia’ is the Latin version first used in 1691, probably derived from ‘oion’ Greek word for egg. My guess is that it’s a word that egg collectors made up to give their hobby a patina of science.

The word ‘oology’ became associated with egg-collecting in the Victorian era but largely disappeared from the ornithological literature in the 1920s, probably because egg-collecting fell out of favour (and was eventually outlawed). The study of eggs waxed and waned throughout the twentieth century with a monumental book—The Avian Egg—by AL and AJ Romanoff published in 1949 being one of the highlights. Over the past decade or so, the study of bird’s eggs has enjoyed a resurgence with new tools available for measuring colours and shapes but few ornithologists use the word oology any more.

Recent books about bird’s eggs


  • Anonymous (1908) Mr. W. C. Hewitson. The Ibis Jubilee Supplement 2: 182–185.
  • Birkhead T (2016) The Most Perfect Thing: Inside (and Outside) a Bird’s Egg. Bloomsbury USA.
  • Hewitson WC (1831-38) British oology: being illustrations of the eggs of British birds, with figures of each species, as far as practicable, drawn and coloured from nature : accompanied by descriptions of the materials and situation of their nests, number of eggs, &c. Newcastle Upon Tyne: Charles Empson [first edition available here]
  • Hewitson WC (1859) Recent discoveries in European oology. The Ibis 1: 76-80
  • Kiff L (2005) History, present status, and future prospects of avian eggshell collections in North America. The Auk 122: 994–999,


  1. ovology: is, according to the dictionary, one variant of oology but I have seen it in print
  2. sound ridiculous when you think about them or repeat them: this is called semantic satiation or wordnesia and can happen with any word
  3. advertisement: in Magazine of Natural History 3 (end matter)—”On the First of January, 1831, will be published, the First Number of British Oology, being illustrations of the Eggs, Nidification, &c. of British Birds
  4. subscribers to British Oology: the full list is at the beginning of the first edition.
  5. Hewitson quotations: from Hewitson 1831 pages 3, 8, and 8-9, respectively
  6. useful for classification: this idea persisted well into the 20th century despite ample evidence that it eggs were not a useful trait for taxonomy. I expect that some of this persistence was driven by a desire to justify the collecting of eggs
  7. museum of oology: the Museum of Comparative Oölogy was started by William L. Dawson in 1916, and is now part of the Santa Barbara Museum of Natural History

George Ord’s warbler

BY: Bob Montgomerie, Queen’s University | 21 May 2018

Cape May Warbler (Wilson 1812, part of Plate LIV)

I have always liked the Cape May Warbler. The male in spring is a handsome bird, but scarce enough here in eastern Ontario that I see only one or two every spring [1]. When I first saw one on migration at Long Point Bird Observatory in the 1960s, my friend and mentor David Hussell said that it was really a misnomer—the species was originally collected on Cape May, NJ, he said, but had hardly ever been seen there since.

There are only three other North American birds named after such a small region of the continent [2], and the others are also misnomers in the sense that they do not represent anything useful about the bird’s range, habitat, appearance or song [3]. While there are rules about priority in the assigning of scientific names to species, common names are largely at the whim of the first person to describe the species, and, in North America, the later machinations of the AOU Check-list committee (now AOS’s North American Classification Committee).

That ‘first’ Cape May Warbler was a male collected by George Ord on a collecting trip with Alexander Wilson on Cape May in May 1812 [4]:

THIS new and beautiful little species was discovered in a maple swamp, in Cape May county, not far from the coast, by Mr. George Ord of this city, who accompanied me on a shooting excursion to that quarter in the month of May last…The same swamp that furnished us with this elegant little stranger, and indeed several miles around it, were ransacked by us both for another specimen of the same; but without success. Fortunately it proved to be a male, and being in excellent plumage, enabled me to preserve a faithful portrait of the original. [5]

Wilson described the bird, painted it (see above), and called it the Cape May Warbler Sylvia maritima in Volume 6 (page 99) of his American Ornithology, published in 1812. It was not seen again on Cape May until September 1920 when Witmer Stone found it there but it has been increasingly recorded—and is now regularly seen—on Cape May during migration ever since [6].

Unbeknownst to Wilson, the bird had already been described  as Motacilla tigrina in 1789 in Johann Friedrich Gmelin’s edition of Linaeus’s Systema naturae:

top of page 985 in Gmelin (1789) describing Motacilla tigrina

But wait, Gmelin says that this is the same species as Brisson’s Ficedula canadensis fusca and F. dominicensis, Buffon’s ‘Figuier tacheté de jaune,’ Edwards’s ‘Spotted Yellow Flycatcher,’ and Pennant’s (1874) ’Spotted Yellow Warbler.’ OK, Buffon, Edwards and Pennant did not give it a scientific name, and Brisson’s F. canadensis is the Chestnut-sided Warbler and his F. dominicensis is the Mangrove Warbler. So Gmelin is considered to be the scientific naming authority for this species, and the species name he gave it, tigrina, is official. He also correctly identified the habitat as ‘Canada’, presumably based on Pennant who said “Inhabits also Canada, which may be its place of summer residence and breeding.” [7]

But how did Gmelin (and the others) who wrote in 1789 even know about this species if the ‘first’ specimen was the one collected by George Ord on Cape May in 1812? The short answer is that Wilson was mistaken, as was Charles Lucien Bonaparte who later wrote about Wilson’s nomenclature [8] and edited editions of Wilson’s American Ornithology after Wilson died in 1813. Since Gmelin, Brisson, Buffon and Pennant were all referring to Edwards’s specimens, Gorge Ord’s warbler was actually the third specimen of what we now call the Cape May Warbler.

Edward’s (1758) Spotted Yellow Fly-catcher (L) and Yellow-tailed Flycatcher (R)

The first specimen of what we now call the Cape May Warbler was actually collected on 1 November 1751 when a male and female landed on a boat about 56 km off the coast of the island of Hispaniola in the Caribbean. George Edwards obtained the specimens and published his painting of the male in 1758 on a plate with an American Redstart (shown to the right). In the plate caption [9], Edwards says these “undescribed small Birds” were collected by Thomas Stack “in a voyage from London to Jamaica.” Of the  female, Edwards says: “the breast in the hen was of a dirty yellow white spotted with dusky, and something less bright on the back; otherwise they are marked very much alike. These birds I believe have never been figured or described until now.” [10]

I have actually always liked the name ‘Cape May Warbler.’ Even though that moniker does not tell us anything useful about the bird, the name has an interesting history, in the same way as the name ‘Lady Ross’s Turaco’ that I wrote about in a previous post. And it’s much better than Boat-off-the-coast-of-Hispaniola Warbler, or Spotted Yellow Fly-catcher.


  • Bonaparte CL (1826) Observations on the Nomenclature of Wilson’s Ornithology. Philadelphia: Anthony Finley.
  • Brisson M-J, Martinet FN (1760) Ornithologie, ou, Méthode contenant la division des oiseaux en ordres, sections, genres, especes & leurs variétés (t.1 (1760)). Parisiis :Ad Ripam Augustinorum, apud Cl. Joannem-Baptistam Bauche, bibliopolam, ad Insigne S. Genovesae, & S. Joannis in Deserto.
  • Burtt Jr EH, Davis Jr WE (2013) Alexander Wilson: The Scot Who Founded American Ornithology. Cambridge, Mass.: Harvard University Press.
  • Edwards, G (1758) Gleanings of Natural History. Part I. London: Printed for author at the Royal College of Physicians.
  • Gmelin JF (1789) Caroli a Linné. Systema naturae per regna tria naturae : secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. (Tom. 1 Pars. 2). Lipsiae: impensis Georg. Emanuel. Beer.
  • Pennant T (1784) Arctic Zoology, 2 vols. London: Henry Hughs.
  • Wilson A (1908-1914) American Ornithology; or, the natural history of the birds of the United States. Vols I-IX. Philadelphia: Bradford and Inskeep. Available here.


  1. Rarity of Cape May Warbler in eastern Ontario: ebird says I am not alone as almost all sightings within 100 km of where I live in Kingston, Ontario, are of 1 bird on a given day.
  2. Area of Cape May: depending on how you measure it, Cape May is no more than 50 km2
  3. Three other North American bird misnomers: Nashville Warbler also named by Wilson in 1811 based on a specimen he collected on migration near Nashville—the bird breeds in the boreal forest of eastern Canada and northeastern USA, as well as in the mountains from BC to California; Philadelphia Vireo named in 1851 by John Cassin based on a bird collected on migration in Bingham’s Woods near Philadelphia where he lived and worked—the bird breeds mainly in Canada from British Columbia to Newfoundland; and the Key West Quail-dove which did once breed in the Florida Keys (including Key West) but is now just a vagrant in Florida having been extirpated as a breeder there in the 1800s—the bird was described by Charles Bonaparte in 1855 based on a specimen from Key West but that was even then the very northern tip of its breeding range that encompasses the Greater Antilles and the Bahamas.
  4. Collected in 1812: since Wilson was writing in the summer of 1812, Burtt and Davies (2013) interpret ‘May last’ as meaning May 1812, but Ord later claimed that the bird was shot in May 1811, possibly as an attempt to show that his bird was collected before a bird that Audubon thought might be the same species. Audubon collected his bird in Kentucky in May 1811, and called it the Carbonated Warbler. See Burtt and Davies (2013 page 341) for further information on this.
  5. Quotation from Wilson: 1812 (vol 6), page 99
  6. Sightings on Cape May: ebird, for example, shows more than 100 sightings since 2011.
  7. Quotation from Pennant: 1784 page 407. Pennant actually called it the Spotted Warbler and not the Spotted Yellow Warbler as Gmelin claimed.
  8. Bonaparte’s nomenclature: see Bonaparte 1824, page 14
  9. Edwards’s plate: is numbered ‘257 and appears between pages 100 and 101 in Edwards (1758)
  10. Quotation from Edwards: 1758 page 102

IMAGES: all from digital copies of the books in the Biodiversity Heritage Library, in the public domain

Lumpers and Splitters

BY: Bob Montgomerie, Queen’s University | 14 May 2018

Almost everyone I know who is interested in birds has their favourite group, and the reasons for those favourites vary widely. For some, the difficulty—and their mastery—of field identification is most appealing: I am thinking peeps, LBJ sparrows, fall wood warblers in North America and leaf (Phyloscopus) warblers in Europe. For others, it’s the beauty of—variously—their songs (wood warblers, thrushes, mimics), their plumages (male wood warblers in spring, hummingbirds, trogons, peafowl), their ability to fly (falcons, hummingbirds, swallows, swifts), their intelligence (corvids, tits, parrots), or their way of life (seabirds, hummingbirds, waterfowl, shorebirds, antbirds, brood parasites, cooperative breeders, lekking species, owls).

Peeps at Moss Landing, California

For many scientists, their favourites are the birds that they have studied most—often as much by accident as by design. Among my ornithologist friends and colleagues, the favourites are coots, murres, manakins, Parids, fairy wrens, acorn woodpeckers, barn swallows, anis, and snow geese. My own favourites are hummingbirds (PhD research), shorebirds and ptarmigan (20 years of arctic research), and seabirds (summer job before PhD).

When I began birding, however, my favourites were the Hylocichla (now Catharus) thrushes and the Empidonax flycatchers, possibly because some species were hard to identify. I was also intrigued by the geographic mosaic of Empidonax ranges and the incredible similarities in their plumages described by Ned Johnson, among others. Why is it that some species in some genera (Dendroica males in springfor example) are so easy to tell apart whereas in other genera (like Empidonax) species can only be distinguished morphologically by careful measurements of a bird in the hand (or so we thought). My own careful examination of Empidonax flycatchers while banding them at Long Point Bird Observatory resulted my first paper in an international journal more than 50 years ago.

Willow (L) and Alder (R) Flycatchers

Because of that early interest in the Empidonax flycatchers, I was both dismayed and intrigued when the AOU split the Traill’s Flycatcher into two species—Alder and Willow—in 1973 on the basis of their song and some morphological traits. Here was a species that I thought I knew well (albeit only on migration), that was actually two species, even more cryptic than the other hard-to-tell-apart species in that genus. This was my first lesson in the fluidity of taxonomy and the possibility that there were almost certainly other cryptic species to be found. I remember wondering, for example, if the Grey-cheeked Thrush might be two species, based on the obvious morphological and geographic differences in the subspecies bicknelli, and that, too, was formally recognized as a separate species by the AOU in 1995.

Throughout the 20th century, there was often a tension between lumpers and splitters [1] when it came to avian taxonomy. Some suggested that the differences between splitting and lumping were like the differences between liberal and conservative governments in democracies. We now recognize, however, that periods of lumping and splitting are the result of changing opinions about species definitions, and the progress of technologies that allow us to distinguish among populations.

A new paper in PLoS ONE by Gaurav Vaidya, Denis Lepage, and Robert Guralnick [2] uses the 136 years of AOU checklists to examine, among other things, the historical patterns of lumping and splitting of the North American avifauna by taxonomists. The first AOU checklist was published in 1886, the production of which was one of the stated reasons for the for the formation of the American Ornithologists’ Union in 1883. Since then, 6 additional full ‘editions’ of the checklist have been published, with 57 supplements published at roughly 2-year intervals between editions.

Since 1886, fully three-quarters of the ~900 North American species have not been involved in what the authors call the ‘correction process’, being either lumped with other species or split into two or more species by the checklist committees. Sixteen percent have been corrected once, and the remaining 10% twice or more. In all, there have been more  lumps (142) than splits (95) in the past 130 years but the pattern of change has been striking. Lumping was initially the norm, probably largely due to the widespread adoption of the Biological Species Concept. But very few species have been lumped since 1980 as the rate of splitting took off, likely because DNA technologies improved and there began a (slight) shift toward a phylogenetic species concept.


Their analysis identified three periods of relative stasis, when there were no corrections to be made, perhaps roughly coinciding with periods of societal upheaval and dramatic scientific changes in taxonomic philosophies and practices.

Vaiyda and colleagues also identify some intriguing examples of  “… a current, ongoing taxonomic recorrection process, in which corrections made in the first half of the 20th century are now being reverted in light of new evidence and better tools. [3]. To the non-scientist this must look like the taxonomists are incredibly indecisive but these recorrections actually (often) reflect the sort of changes in species definitions and technologies described above. For example, in 1923 the Common Galllinule (Gallinula galeata) of North America was lumped with the Common Moorhen (Gallinula chloropus) of Europe because they were thought, based on their breeding ranges and morphologies, to be subspecies. Then, in 2011, those species were split again, recognizing the differences in their vocalizations, bill and shield morphologies, and mtDNA.

Common Gallinule (L) and Common Moorhen (R)

If the trend shown in the graph continues—and there is no reason to expect that it will not—the number of splits will soon surpass the number of lumps. Recently, George Barrowclough and colleagues have speculated that the level of splitting resulting from the application of genomic tools and the phylogenetic species concept will almost double the number of species recognized worldwide—to 18,000—before too long. The implications of this for conservation, for understanding the evolutionary history of birds, and for my life list, are huge.


  • American Ornithologists’ Union. 1995. Fortieth supplement to the American Ornithologists’ Union Check-list of North American Birds. Auk 112: 819-830.

  • Barrowclough GF, Cracraft J, Klicka J, Zink RM (2016) How many kinds of birds are there and why does it matter? PLoS One. 2016; 11: e0166307. https://doi.org/10.1371/journal.pone.0166307 PMID: 27880775
  • Chesser RT, Banks RC, Barker FC, Cicero C, Dunn JL, Kratter AW, Lovette IJ, Rasmussen PC, Remsen Jr JV, Rising JD, Stotz DF, Winker K. (2011) Fifty-Second Supplement to the American Ornithologists’ Union Check-List of North American Birds. Auk 128: 600-613
  • Johnson NK (1980) Character variation and evolution of sibling species in the Empidonax difficilis-flavescens complex (Aves: Tyrannidae). University of California Publications in Zoology 112: 1-151.

  • Mayr E (1982) The Growth of Biological Thought. Cambridge, Mass: Belknap Press.

  • Stone W, Oberholser HC, Dwight J, Palmer TS, Richmond CW (1923) Eighteenth Supplement to the American Ornithologists’ Union Check-List of North American Birds. Auk 40:513–525.

  •  Vaidya G, Lepage D, Guralnik R (2018) The tempo and mode of the taxonomic correction process: How taxonomists have corrected and recorrected North American bird species over the last 127 years. PLoS ONE 13(4): e0195736. https:// doi.org/10.1371/journal.pone.0195736


  1. lumpers and splitters: respectively, taxonomists who favour placing similar populations under the umbrella of a single species versus those who seek to identify distinct populations as separate species. Ernst Mayr (1982, page 240) claimed that “As a general rule one can say that most taxonomic groups pass through a phase of rather intensive splitting when they are studied more actively, but that the splitting phase is reversed when the knowledge of the group reaches greater maturity.” I think this new paper by Vaidya et al. (2018) shows that statement to be incorrect and may reflect Mayr’s view that his Biological Species Concept was sacrosanct.
  2. while this is an excellent analysis the paper is technically detailed, a necessity given the changes in the way species have been defined and the changes in coverage of the checklist. I have tried to distill some of those details here but I am no taxonomist.
  3. quotation: from Vaidya et al (2018 page 2)

IMAGES: peeps by the author; graph redrawn by the author from Vaidya et al (2018, Figure 1); Flycatchers from https://u.osu.edu/biomuseum/2015/09/28/examples-of-sibling-species/comment-page-1/; Gallinula spp. from Wikimedia Commons, in the public domain.

A Bird’s Eye View

BY: Bob Montgomerie, Queen’s University | 17 April 2018

When I started my PhD at McGill University, in 1973, I was thrilled to discover that the university had a library devoted just to ornithology: the Blacker-Wood Library of Zoology and Ornithology. This library was a primarily large room located in the basement of the university’s  immense Redpath Library just down the road from the Biology Building. Besides a fabulous collection of contemporary books and journals about birds, the library also had a rare book room full of treasures like the feather book of Dionisio Minaggio. It also had a hand-coloured copy of John Ray’s Ornithology of Francis Willughby published in 1776 and ostensibly given as a present to Samuel Pepys, the famous 17th century diarist [1]. 

I remember the librarian, Eleanor MacLean, telling me that the library subscribed to more than 100 ornithological journals and newsletters. That seems like a lot but they did get the separate bird journals published by many of the provinces in Sweden, as well as a dozen or more in foreign languages that I could not read, so that total might not have been far off. It was a real treat for me to spend every Friday morning poring over the latest acquisitions. While I love the convenience of the internet, and rapid search engines, there was something oddly rewarding about opening the latest issues of journals from around the world, all devoted to the study of birds.

That library was founded in 1920 by Casey Wood, a Canadian-American [2] ophthalmologist who was also an avid—OK, obsessive—book collector. On Friday (20 April), I will be going to Montreal to participate in a symposium celebrating his contributions to the library in particular and to ornithology in general.

Wood wrote several papers about birds but his signal ornithological work was a little-known volume called The Fundus Oculi of Birds, published in 1917. Because Wood was an ophthalmologist and immensely curious, he thought it might be interesting to use the tools of his trade to study the eyes of birds. To do that, he employed the techniques that he had used in his practice, and further developed some procedures for studying the eyes of birds. His main interest was the structures of the fundus oculi, at the back of the eye—the retina, the fovea(s), the nerves and the pecten.

2018-04-16 21.11.16
Wood adapted the methods he used to strudel the eyes of his patients (left) to examine the fundus oculi of birds (right). From Wood (1917)

64BCC83D-A67F-46C9-8914-7F692BDF0D6AWood realized early on that his observations would be most useful if he could somehow illustrate what he was seeing through his ophthalmoloscope. In those days, photography was simply not advanced enough to provide enough depth of focus:

In spite of recent advances in that direction, attempts to reproduce the colored (ophthalmoscopic) appearances of the fundus by photography have so far failed. [3]

Instead he employed the talents of Arthur William Head [4], a celebrated UK artist, to draw and paint the fundus oculi of more than 80 bird species. Wood does not record how Head did this—did Wood train Heath to use the opthalmoscope or did he roughly sketch what he saw and then work with Head to make Head’s illustrations match what Wood saw? Wood says that it takes a lot of experience to be able to use the ophthalmoloscope but maybe he was able to teach Heath his techniques. Wood also says that his methods allowed only a short period of observation of the fundus oculi so it is remarkable how detailed these illustrations are, however they were produced.

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Arthur Head’s paintings of the fundus oculi of Great Black-backed Gull (left) and African Penguin (right) showing the pecten (black) and retina (red or brown). From Wood (1917)

Perhaps surprisingly, Wood took a very modern approach to his subject, as he attempted to examine at least one species in each avian order to see if there were patterns related to the bird’s way of life—an early example of what we now call comparative analysis.

 The oculi of Birds exhibits a great variety of areas of distinct vision, and these correspond closely to the habits and habitat of these animals especially their methods of obtaining food, of escape from enemies, of migration, of reproduction, etc. [3]

But he also wanted to determine whether the fundus oculi might be a useful taxonomic tool, helping to define the evolutionary relationships among species. To that end, he sampled and illustrated the fundus oculi of birds from 24 of the Orders of birds that were recognized in those days, missing only 5 of the Orders that we (or at least some authorities) recognize today (Turniciformes, Craciformes, Gabuliformes, Coliiformes and Musophagiformes). There was a bit of a taxonomic signal there, in Wood’s opinion, but not clear enough to be useful. 

Side view of the eyes of an Ostrich (left) and  Kiwi (right) showing a clear difference in pecten (black) structure that Wood thought might be related to visual acuity, with the kiwi needing less as it hunts mainly by smell at night. From Wood (1917)

 Instead, Wood showed nicely that the pecten size and shapevwere likely related to visual acuity, and that some birds have two foveas, related either to visual acuity or more likely the need to switch from binocular to monocular vision while foraging. Even today, a century later, we still do not have definitive studies of these traits in the fundus oculi, as far as I can tell.

 Wood also found that the pecten degenerated in domesticated birds suggesting to me that it is a costly structure that becomes smaller under relaxed selection when visual acuity is no longer important for foraging or survival.

 Reading Wood’s Fundus Oculi Book for my talk in Montreal reminded me once again of the tremendous value in reading the older literature once in a while. I have been interested in avian vision for about 25 years but had never really thought or read about the pecten before. To the best of my knowledge, many of the patterns that Wood described have not been further investigated even though we now have all of the tools needed to measure and quantify the structures he described and illustrated. Wood’s book is not an easy read as it is largely descriptive and lacks focus (no pun intended). There are enough gems buried there, though, that anyone interested in the vision of birds might want to have a look at this interesting book.


  • Montgomerie R, Birkhead TR (2009) Samuel Pepys’s hand-coloured copy of John Ray’s ‘The Ornithology of Francis Willughby’ (1678). Journal of Ornithology 150:883-891  DOI 10.1007/s10336-009-0413-3
  • Wood CA (1917) The Fundus OCuli of BIrds ESefially as Viewed by the Ophthalmoloscope: A Study in Comparative Anatomy and Physiology. Chicago: Lakeside Press. Available here


1. Pepys’s  copy of Willughby and Ray’s Ornithology: see Montgomerie and Birkhead  (2009)

2. Casey Albert Wood: (1856-1942) was born in Wellington, Ontario, attended high school in Ottawa, and got his medical degrees from McGill University. He eventually settled in Chicago where he practiced ophthalmology. See here for details

3. Quotations: from Wood 1917 page 7

4. Arthur William Head: (1861-1930) was a celebrated artist who lived in London, England, see here for examples of his work

The Utmost Harmony

BY: Bob Montgomerie, Queen’s University | 9 April 2018

I gave my first research talk at a ‘big’ international conference at the AOU meeting at Haverford College (Pennsylvania) in 1976. I talked about my work on Mexican hummingbirds and I was nervous, in part because Frank Gill—who was then doing great work on hummingbirds—was talking right before me. The chair of our session was some old guy with unruly grey hair. Though I really wanted to hear Frank’s talk, I was too busy thinking about what I was going to say to actually pay attention to his words. Until, that is, when he finished answering a couple of questions. As he was about to leave the stage, Frank said to the chair “Thanks, Ernst”. “OMG”, I thought [1], “that’s Ernst Mayr, and I may not survive this.”

Ernst Mayr ca 1976

I completed my presentation on autopilot, out of sheer terror. But Professor Mayr asked me a couple of excellent questions and thereby, very graciously, put me at ease and made my presentation seem like a success. I had been to a few AOU meetings before but that incident convinced me that I had found my academic home. It seemed that everyone from the most famous—Mayr and Gill—to the greenest student (me) could talk about birds in an environment characterized by the utmost harmony.

Indeed, that’s how someone [2] described the first AOU meeting, in a report in the Bulletin of the Nuttall Ornithological Club in 1883:

The session of the Convention occupied three days, and was marked throughout with the utmost harmony; at adjournment…hearty expressions of satisfaction with the results of the session were heard from all who had shared in its deliberations. The general good feeling rose to a degree of enthusiasm auguring well for the future work and prosperity of the Union, the organization of which, under such auspicious circumstances, cannot fail to mark an important era in the progress of ornithology in America. [3]

He was right, that first convention did augur well for the future work of the ‘Union’—and it has gone from strength to strength over the past 135 years. The AOU was the gifted child of the Nuttall Ornithological Club in 1883 and the proud parent (along with the Cooper Ornithological Society) of the American Ornithological Society (AOS) in 2016.

El Conquistador Hotel, Tucson, Where the 2nd AOS meeting is about to begin on 11 April 2018

Today I am in Tucson waiting for the start of the 2nd annual AOS meeting. I am anticipating some great science, some reconnecting with old friends, and seeing some interesting birds. I am not really a birder and especially not a twitcher, so I will not make the trek to Madera Canyon to see the Elegant Trogon reported there last week. This morning though, I watched  a pair of Verdins building a nest, and spent an hour in the midst of a dozen pairs of courting Great-tailed Grackles. I always prefer watching behaviour over searching for rarities. But I digress.

That first AOU meeting in 1883 was the result of a letter sent on 1 August 1883 by three officials [4] of the Nuttall Ornithological Club to 46 American and 2 Canadian ornithologists,


You are cordially invited to attend a Convention of American Ornithologists, tiobe held in New York City, beginning on Seotember 26, 1883, for the ourpose of founding an AMERICAN ORNITHOLOGISTS UNION, upon a basis similar to that of the “British Ornithologists Union”…The object of the Union will be the promotion of social and scientific intercourse between American ornithologsts, and their cooperation in whatever may tend to the advancement of Ornithology in North America…” [3]

Twenty-one men attended the 3-day conference in the library if the American Museum of Natural History. They declared themselves to be founders of the AOU, along with Spencer Fullerton Baird and J A Allen who were unable to attend. Their first order of business was to establish a constitiution for the new society followed by the election of other ornigthologists—all men as far as I can tell—to various classes of membership: 21 Foreign, 20 Corresponding, and 81 Associate in addition to the 47 Active members that included the Founders.

They also established six committees that nicely reflected 5 of the major ornithological interests of the day: Classification of North American Birds, Migration, Avian Anatomy, Oölogy, and Faunal Areas. The sixth committee was charged “to investigate the eligibilibity or ineligibility of the European House Sparrow in North America”. I do not know what that sixth committee eventually decided, but it is clear from events over the next century that the House Sparrow did not care.


  • Anonymous (1883) The American Ornithologists’ Union. Bulletin of the Nuttall Ornithological Club 8: 221-226


1. OMG: I did not, of course, think that in 1976, as it did not enter the slang lexicon for another 20 years

2.  someone described that first AOU meeting: see Anonymous (1883); normally i would have assumed it was the editor of the journal but that was J A Allen who was ill and could not attend the meeting

3. quotations from Anonymous (1883)

4, three Nuttall Club officials: were J A Allen (editor of the Nuttall Bulletin), Elliott Coues (associate editor) and William Brewster (President of the Nuttall Club)