Ornithology

Article	Citations
Bird migration within the Neotropics	37
A roadmap to identifying and filling shortfalls in Neotropical ornithology	37
Insectivorous birds in the Neotropics: Ecological radiations, specialization, and coexistence in species-rich communities	35
Integrative taxonomy and geographic sampling underlie successful species delimitation	33
Current methods and future directions in avian diet analysis	31
Plumage patterns: Ecological functions, evolutionary origins, and advances in quantification	28
An overview of speciation and species limits in birds	24
The genomic revolution and species delimitation in birds (and other organisms): Why phenotypes should not be overlooked	23
Migration distance is a fundamental axis of the slow-fast continuum of life history in boreal birds	20
Sixty-first Supplement to the American Ornithological Society’s Check-list of North American Birds	19
Bill size, bill shape, and body size constrain bird song evolution on a macroevolutionary scale	18
Testing the simple and complex versions of Gloger’s rule in the Variable Antshrike (Thamnophilus caerulescens, Thamnophilidae)	16
Sixty-second Supplement to the American Ornithological Society’sCheck-list of North American Birds	16
Elevational niche-shift migration: Why the degree of elevational change matters for the ecology, evolution, and physiology of migratory birds	15
The five million bird eggs in the world’s museum collections are an invaluable and underused resource	15
Evaluating the impacts of metabarcoding primer selection on DNA characterization of diet in an aerial insectivore, the Purple Martin	15
Phylogeny based on ultra-conserved elements clarifies the evolution of rails and allies (Ralloidea) and is the basis for a revised classification	14
Conservative plumage masks extraordinary phylogenetic diversity in the Grallaria rufula (Rufous Antpitta) complex of the humid Andes	13
Mitochondrial genomes and thousands of ultraconserved elements resolve the taxonomy and historical biogeography of the Euphonia and Chlorophonia finches (Passeriformes: Fringillidae)	13
Genomic and plumage variation across the controversial Baltimore and Bullock’s oriole hybrid zone	13
Haemosporidian parasites of Neotropical birds: Causes and consequences of infection	13
The American Kestrel (Falco sparverius) genoscape: implications for monitoring, management, and subspecies boundaries	12
Evolution of the preformative molt in Cardinalidae correlates with transitions from forest to open habitats	11
Sixty-fourth Supplement to the American Ornithological Society’s Check-list of North American Birds	11
Temperature and vegetation complexity structure mixed-species flocks along a gradient of elevation in the tropical Andes	11

Genomic and plumage variation in Vermivora hybrids	11
The costs of ignoring species detectability on functional diversity estimation	10
Genomic and geographic diversification of a “great-speciator” (Rhipidura rufifrons)	9
DNA metabarcoding reveals broad woodpecker diets in fire-maintained forests	9
The Pacific as the world’s greatest theater of bird migration: Extreme flights spark questions about physiological capabilities, behavior, and the evolution of migratory pathways	9
Species limits in birds: Australian perspectives on interrelated challenges of allopatry, introgression of mitochondrial DNA, recent speciation, and selection	9
Ultraconserved elements resolve the phylogeny and corroborate patterns of molecular rate variation in herons (Aves: Ardeidae)	9
Systematics and conservation of an endemic radiation of Accipiter hawks in the Caribbean islands	9
Comparative phylogeographic analysis suggests a shared history among eastern North American boreal forest birds	9
Extensive hybridization between two Andean warbler species with shallow divergence in mtDNA	8
Season, anthocyanin supplementation, and flight training have mixed effects on the antioxidant system of migratory European Starlings	8
DNA metabarcoding reveals broadly overlapping diets in three sympatric North American hummingbirds	8
Preston’s universal formula for avian egg shape	8
Heat shock protein gene expression varies among tissues and populations in free-living birds	8
Ecological and evolutionary significance of molt in lowland Neotropical landbirds	8
Army-ant following in Neotropical birds: A review and prospectus	8
Latitude does not influence cavity entrance orientation of South American avian excavators	8
Dry season intensity has equivocal effects on the nutritional condition of understory birds in a Neotropical forest	8
Rapid recovery by fat- and muscle-depleted Blackpoll Warblers following trans-oceanic migration is driven by time-minimization	8
Performance of a points-based scoring system for assessing species limits in birds	8
Genetic data and niche differences suggest that disjunct populations of Diglossa brunneiventris are not sister lineages	8
Genetic and morphological differentiation among populations of the Rivoli’s Hummingbird (Eugenes fulgens) species complex (Aves: Trochilidae)	7
Multiple lines of evidence indicate ongoing allopatric and parapatric diversification in an Afromontane sunbird (Cinnyris reichenowi)	7
Ecological and evolutionary drivers of geographic variation in songs of a Neotropical suboscine bird: The Drab-breasted Bamboo Tyrant (Hemitriccus diops, Rhynchocyclidae)	7
Extinct crane-like birds (Eogruidae and Ergilornithidae) from the Cenozoic of Central Asia are indeed ostrich precursors	7
Reduced diurnal activity and increased stopover duration by molting Swainson’s Thrushes	6
Climate change and maladaptive wing shortening in a long-distance migratory bird	6
When to depart from a stopover site? Time since arrival matters more than current weather conditions	6
An early Oligocene stem Galbulae (jacamars and puffbirds) from southern France, and the position of the Paleogene family Sylphornithidae	6
Haemosporidian prevalence and community composition vary little across a chickadee hybrid zone	6
A habitat-based approach to determining the effects of drought on aridland bird communities	6
Vertical sexual habitat segregation in a wintering migratory songbird	6
Genome-wide data reveal paraphyly in the sand plover complex (Charadrius mongolus/leschenaultii)	5
Neither sex appears to benefit from divorce within migratory Northern Flickers consistent with accidental loss and bet-hedging	5
Updating splits, lumps, and shuffles: Reconciling GenBank names with standardized avian taxonomies	5
Mixed-species flocking is associated with low arthropod detectability and increased foraging efficiency by Yungas forest birds in Argentina	5
Landscape cover type, not social dominance, is associated with the winter movement patterns of Snowy Owls in temperate areas	5
Put some muscle behind it: Understanding movement capacity of tropical birds	5
Divergence in plumage, voice, and morphology indicates speciation in Rufous-capped Warblers (Basileuterus rufifrons)	5
Variation in incubation length and hatching asynchrony in Eastern Kingbirds: Weather eclipses female effects	5
High-intensity flight feather molt and comparative molt ecology of warblers of eastern North America	5
Exceptional variation in the appearance of Common Murre eggs reveals their potential as identity signals	5
Application of a global age-coding system (“WRP”), based on molts and plumages, for use in demographic and other studies of birds	5
The shape of avian eggs: Assessment of a novel metric for quantifying eggshell conicality	5
Nest cavity reuse by the cooperatively breeding Acorn Woodpecker	5
Breeding performance of Common Terns (Sterna hirundo) does not decline among older age classes	5
Female and male song exhibit both parallel and divergent patterns of cultural evolution: A long-term study of song structure and diversity in tropical wrens	5
A new genus and species of tanager (Passeriformes, Thraupidae) from the lower Yungas of western Bolivia and southern Peru	5
Addendum to the Sixty-first Supplement to the American Ornithological Society’s Check-list of North American Birds	5
Physiological condition reflects polymorphism at the toll-like receptors in a colonial waterbird	4

Experimental evidence that social information affects habitat selection in Marbled Murrelets	4
Mass gain and stopover dynamics among migrating songbirds are linked to seasonal, environmental, and life-history effects	4
Egg spottiness reflects female condition, physiological stress, and ornament expression in a common rallid species	4
Underestimated Neotropical diversity: Integrative taxonomy reveals two unrelated look-alike species in a suboscine bird (Pachyramphus albogriseus)	4
Endogenous biomarkers reveal diet partitioning among three sympatric species of swallows	4
The Big Boom Theory: The Common Nighthawk wing-boom display delineates exclusive nesting territories	4
Plasma metabolite indices are robust to extrinsic variation and useful indicators of foraging habitat quality in Lesser Scaup	4
Morphology, vocalizations, and mitochondrial DNA suggest that the Graceful Prinia is two species	4
Low levels of hybridization between domestic and wild Mallards wintering in the lower Mississippi Flyway	4
Avian taxonomy in turmoil: The 7-point rule is poorly reproducible and may overlook substantial cryptic diversity	4
Early nest initiation and vegetation density enhance nest survival in Wild Turkeys	4
Black-capped Chickadees (Poecile atricapillus) can identify individual females by their fee-bee songs	4
Cryptic speciation in the Warbling Vireo (Vireo gilvus)	4
Contact calls of island Brown-throated Parakeets exhibit both character and variance shifts compared to calls of their mainland relatives	4
Haemosporidian parasite diversity and prevalence in the songbird genusJuncoacross Central and North America	3
Resource allocation underlies parental decision-making during incubation in the Manx Shearwater	3
Faster growth and larger size at crèche onset are associated with higher offspring survival in Adélie Penguins	3
Extensions and limitations of MacArthur (1958): A review of ecological and evolutionary approaches to competition and diet in the New World wood warblers (Parulidae)	3
Winds aloft over three water bodies influence spring stopover distributions of migrating birds along the Gulf of Mexico coast	3
Phylogenomic analyses reveal non-monophyly of the antbird generaHerpsilochmusandSakesphorus(Thamnophilidae), with description of a new genus forHerpsilochmus sellowi	3
Phylogenomic analysis confirms the relationships among toucans, toucan-barbets, and New World barbets but reveals paraphyly ofSelenideratoucanets and evidence for mitonuclear discordance	3
Lineage diversity in a widely distributed New World passerine bird, the House Wren	3
Body size is associated with yearling breeding and extra-pair mating in the Island Scrub-Jay	3
A neuroendocrine perspective on the origin and evolution of cooperative breeding	3
Pacific Barrow’s Goldeneye refine migratory phenology in response to overwintering temperatures and annual snowmelt	3
Taming the temperature: Sagebrush songbirds modulate microclimate via nest-site selection	3
Context-specific behavior serves as a mechanism of interspecific cohesion in mixed-species flocks	3
Eastern Bluebirds (Sialia sialis) use color patterning, but not the colors themselves, as a cue to eject interspecific parasitic eggs	3
Filoplume morphology covaries with their companion primary suggesting that they are feather-specific sensors	3
Vulnerable Neotropical migratory songbird demonstrates flexibility in space use in response to rainfall change	2
High within-clutch repeatability of eggshell phenotype in Barn Swallows despite less maculated last-laid eggs	2
Modeling phenological reaction norms over an elevational gradient reveals contrasting strategies of Dusky Flycatchers and Mountain Chickadees in response to early-season temperatures	2
Life-history implications of migratory Lesser Sandhill Cranes replacing adjacent blocks of primaries synchronously	2
A desert songbird with no confamilials in the Western Hemisphere (Verdin,Auriparus flaviceps) investigates divergent conspecific songs	2
Sixty-third supplement to the American Ornithological Society’sCheck-list of North American Birds	2
Genomic variation in the Black-throated Green Warbler (Setophaga virens) suggests divergence in a disjunct Atlantic Coastal Plain population (S. v. waynei)	2
Experimentally reduced feather microbial loads improve reproductive performance in captive Zebra Finches	2
Nestling Savannah Sparrows and Tree Swallows differ in their sensitivity to weather	2
Estimating egg mass–body mass relationships in birds	2
Beaver activity and red squirrel presence predict bird assemblages in boreal Canada	2
Pro-inflammatory immune response is linked to wintering habitat in a migratory shorebird	2
Studying individual-level interactions can transform our understanding of avian mixed-species flocks	2
Evidence of differing staging strategies between adult and juvenile Semipalmated Sandpipers highlights the importance of small staging sites in Atlantic Canada	2
Hatching failure is greater in altricial bird species with cavity nests and large clutches	2
Asymmetric song recognition does not influence gene flow in an emergent songbird hybrid zone	2
Corrigendum to: Phylogeny based on ultra-conserved elements clarifies the evolution of rails and allies (Ralloidea) and is the basis for a revised classification	2
Sexual dichromatism may not be a good index of sexual or natural selection in the blue cardinalids (Aves: Passeriformes)	2
Threshold models improve estimates of molt parameters in datasets with small sample sizes	2
Ecological release and insular shifts in avian morphological traits in the Caribbean	2
Extraordinary sperm to egg ratios in seabirds	2
Does habitat partitioning by sympatric plovers affect nest survival?	2
Interannual consistency of migration phenology is season- and breeding region-specific in North American Golden Eagles	2
Anthelmintic drugs modulate the acute phase immune response but not the microbiota in wild Song Sparrows	1
Banding data show hummingbirds have high rates of hybridization	1
Plumage coloration differs between offspring raised in natural cavities and nestboxes	1
How Veeries vary: Whole genome sequencing resolves genetic structure in a long-distance migratory bird	1
Neighbors matter: Vocal variation in Gentoo Penguins depends on the species composition of their colony	1
Sulfur isotopic discrimination factors differ among avian tissues and diets: Insights from a case study in Gentoo Penguins	1
Manipulating parental condition affects brood sex ratio, immunocompetence, and early chick mortality in two gull species differing in sexual size dimorphism	1
Ultraconserved elements support the elevation of a new avian family, Eurocephalidae, the white-crowned shrikes	1
Thank You to the Reviewers of the 2021 Ornithology, Volume 138	1
Birds that breed exclusively on islands have smaller clutches	1
Sex, body size, and winter weather explain migration strategies in a partial migrant population of American Kestrels	1
Reproductive roles as likely drivers of sexual dimorphism in New Zealand’s endangered mountain parrot, the Kea	1
No evidence that endohelminth parasites cause selection against hybrid orioles across the Baltimore–Bullock’s Oriole hybrid zone	1
Cultural conformity and persistence in Dickcissel song are higher in locations in which males show high site fidelity	1
Gradual transitions in genetics and songs between coastal and inland populations of Setophaga townsendi	1
Female and male plumage brightness is positively correlated among populations of the dichromatic Variable Seedeater	1
Elevational differences in migration phenology of Lazuli Buntings do not support selection-based hypotheses for protandry	1
The high-energy aerial insectivore lifestyle of swallows does not produce clear thermogenic side effects	1
Professional ethics survey identifies strengths and areas for improvement in the American Ornithological Society	1
Machine learning reveals that climate, geography, and cultural drift all predict bird song variation in coastal Zonotrichia leucophrys	1
The biotic and abiotic drivers of timing of breeding and the consequences of breeding early in a changing world	1
Winter range shifts and their associations with species traits are heterogeneous in eastern North American birds	1
The evolution of enclosed nesting in passerines is shaped by competition, energetic costs, and predation threat	1
Extensive variation in feather ornaments of Whiskered Auklets in the Aleutian Islands reflects age, sex, condition, and geography	1
No apparent trade-off between the quality of nest-grown feathers and time spent in the nest in an aerial insectivore, the Tree Swallow	1
Experimental warming of embryos accelerates metabolism of postnatal songbirds, influences growth, but has no effects on parental feeding and brooding rates	1
Unmasking hidden genetic, vocal, and size variation in the Masked Flowerpiercer along the Andes supports two species separated by Northern Peruvian Low	1
Causes and consequences of nest-site fidelity in a tropical lekking bird: Win-stay-lose-shift tactics are unrelated to subsequent success, but site-faithful females nest earlier	1

Diversification and dispersal in the Americas revealed by new phylogenies of the wrens and allies (Passeriformes: Certhioidea)	1
Considerations for fitting occupancy models to data from eBird and similar volunteer-collected data	1
Habitat connectivity, gene flow, and population genetic structure in a Neotropical understory insectivore, the Rufous-and-white Wren	1
The adaptive significance of off-lek sociality in birds: A synthetic review, with evidence for the reproductive benefits hypothesis in Long-wattled Umbrellabirds	1
Barn Swallows in East Asia show strong tolerance against nest mites	1
Long-term winter food supplementation shows no significant impact on reproductive performance in Mountain Chickadees in the Sierra Nevada Mountains	1
Irruptive fall migrations are linked to elevated breeding abundance but are not associated with body condition or stopover duration in Northern Saw-whet Owls	1
Satellite tracking of American Woodcock reveals a gradient of migration strategies	1
Telomere length links with physiological phenotype and breeding patterns in a long-lived seabird	1
Punctuated evolution of bill morphology in the largest family of songbirds (Thraupidae)	1
100 Years Ago in the American Ornithologists’ Union	1
Genomic and acoustic differences separate Lilian’s Meadowlark (Sturnella magna lilianae) from Eastern (S. magna) and Western (S. neglecta) meadowlarks	1
Long-term, not short-term, temperatures predict timing of egg laying in European Starling	1
Lesser Woodcreepers excavate nest cavities in trees	1
Extended molt phenology models improve inferences about molt duration and timing	1
Painting the Bunting: Carotenoids and structural elements combine to produce the feather coloration of the male Painted Bunting	1
DNA metabarcoding reveals rangewide variation in aquatic diet of a riparian avian insectivore, the Prothonotary Warbler	1
Singing on the nest is a widespread behavior in incubating Northern Mockingbirds and increases probability of nest predation	1
Wildfires and mass effects of dispersal disrupt the local uniformity of type I songs of Hermit Warblers in California	1
Community-sourced sightings of atypical birds can be used to understand the evolution of plumage color and pattern	1
Sociality and morphology differentiate niches of 13 sympatric Amazonian woodcreepers (Dendrocolaptinae)	1
Distinctive mitogenomic lineages within populations of White-tailed Eagles	1