[Ornithology • 2024] Patagona chaski • Extreme Elevational Migration spurred Cryptic Speciation in Giant Hummingbirds (Apodiformes: Trochilidae)

 

Patagona chaski   

Patagona gigas  (Vieillot, 1824)

in Williamson, Gyllenhaal, Bauernfeind, Baumann, Gadek, Marra, Ricote, Valqui, Bozinovic, Singh & Witt, 2024. 

DOI: 10.1073/pnas.2313599121 

  twitter.com/JL_Williamson

 

Significance: 

Biodiversity varies from place to place because the range of climates suitable for any one species tends to be limited. The giant hummingbird appears to defy this tendency, occurring across the broadest range of environments of any hummingbird. We asked whether its migration, physiology, or genetics explain its climate generalism, potentially illuminating mechanisms of niche breadth evolution. Microtracking devices revealed an epic migration from the Chilean coast to the Peruvian Andes, with an extreme, >4,100-m elevational shift and corresponding performance trade-offs. Genomes revealed that migrant and resident populations diverged in the Pliocene and have since evolved under phenotypic stasis. A migratory shift enabled climatic niche expansion, leading to speciation and niche subdivision, consistent with diversification by niche breadth oscillation.

Abstract

The ecoevolutionary drivers of species niche expansion or contraction are critical for biodiversity but challenging to infer. Niche expansion may be promoted by local adaptation or constrained by physiological performance trade-offs. For birds, evolutionary shifts in migratory behavior permit the broadening of the climatic niche by expansion into varied, seasonal environments. Broader niches can be short-lived if diversifying selection and geography promote speciation and niche subdivision across climatic gradients. To illuminate niche breadth dynamics, we can ask how “outlier” species defy constraints. Of the 363 hummingbird species, the giant hummingbird (Patagona gigas) has the broadest climatic niche by a large margin. To test the roles of migratory behavior, performance trade-offs, and genetic structure in maintaining its exceptional niche breadth, we studied its movements, respiratory traits, and population genomics. Satellite and light-level geolocator tracks revealed an >8,300-km loop migration over the Central Andean Plateau. This migration included a 3-wk, ~4,100-m ascent punctuated by upward bursts and pauses, resembling the acclimatization routines of human mountain climbers, and accompanied by surging blood-hemoglobin concentrations. Extreme migration was accompanied by deep genomic divergence from high-elevation resident populations, with decisive postzygotic barriers to gene flow. The two forms occur side-by-side but differ almost imperceptibly in size, plumage, and respiratory traits. The high-elevation resident taxon is the world’s largest hummingbird, a previously undiscovered species that we describe and name here. The giant hummingbirds demonstrate evolutionary limits on niche breadth: when the ancestral niche expanded due to evolution (or loss) of an extreme migratory behavior, speciation followed.

  

  

 

Jessie L. Williamson, Ethan F. Gyllenhaal, Selina M. Bauernfeind, Matthew J. Baumann, Chauncey R. Gadek, Peter P. Marra, Natalia Ricote, Thomas Valqui, Francisco Bozinovic, Nadia D. Singh, and Christopher C. Witt. 2024.  Extreme Elevational Migration spurred Cryptic Speciation in Giant Hummingbirds. PNAS. 121 (21); e2313599121. DOI: 10.1073/pnas.2313599121 

  twitter.com/JL_Williamson/status/1790397976550011094

The proposed scientific name for the resident northern population is Patagona chaski. “Chaski” is the word for messenger in Quechua, a family of Indigenous languages that spread from Peru to other neighboring countries.

 news.cornell.edu/stories/2024/05/worlds-largest-hummingbird-actually-two-species

[Ornithology • 2021] Florisuga mellivora • Male-like Ornamentation in Female Hummingbirds results from Social Harassment rather than Sexual Selection

White-necked Jacobin  Florisuga mellivora (Linnaeus, 1758)

in Falk, Webster & Rubenstein, 2021. 

DOI:  10.1016/j.cub.2021.07.043

 twitter.com/JJinsing 

Highlights

• Female white-necked jacobins are polymorphic—30% have male-like plumage

• All juveniles have male-like plumage, excluding sexual selection as an explanation

• Male-like females receive less con- and heterospecific social harassment

• Thus, male-like ornamentation in females can arise purely through non-sexual means

Summary

Ornamentation is typically observed in sexually mature adults, is often dimorphic in expression, and is most apparent during breeding, supporting a role for sexual selection in its evolution. Yet, increasing evidence suggests that nonsexual social selection may also have a role in the evolution of ornamentation, especially in females. Distinguishing between these alternatives remains challenging because sexual and nonsexual factors may both play important and overlapping roles in trait evolution. Here, we show that female ornamentation in a dichromatic hummingbird, the white-necked jacobin (Florisuga mellivora), cannot be explained by sexual selection. Although all males are ornamented, nearly 30% of females have male-like plumage. Remarkably, all juveniles of both sexes express ornamented plumage similar to adult males (androchromatism), but 80% of females acquire non-ornamented plumage (heterochromatism) as they age. This unique ontogeny excludes competition for mates as an explanation for female ornamentation because non-reproductive juveniles are more likely to be ornamented than adults. Instead, avoidance of social harassment appears to underlie this female-limited polymorphism, as heterochrome taxidermy mounts received more aggressive and sexual attention than androchrome mounts from this and other hummingbird species. Monitoring electronically tagged birds at data-logging feeders showed that androchrome females accessed feeders more than heterochrome females, presumably because of reduced harassment. Our findings demonstrate that ornamentation can arise purely through nonsexual social selection, and this hypothesis must be considered in the evolution of not only female-limited polymorphism but also the spectacular ornamentation often assumed to result from sexual selection.

 

Keywords: social selection, sexual selection, ornamentation, sexual dimorphism, plumage coloration, ontogeny, female-limited polymorphism, hummingbird, Trochilidae, Florisuga mellivora

Both male and female White-necked Jacobins fan their tails during courtship or aggressive interactions. Because this bird also has its wings partially raised it's likely an aggressive stance.

Photo by Brian Sullivan/Macaulay Library at the Cornell Lab of Ornithology.

The left and center images show adult female and adult male plumages, respectively.

Right image shows juvenile plumage.

 

Jay J. Falk, Michael S. Webster and Dustin R. Rubenstein. 2021. Male-like Ornamentation in Female  Hummingbirds results from Social Harassment rather than Sexual Selection. Current Biology. DOI:  10.1016/j.cub.2021.07.043

 twitter.com/JJinsing/status/1430950674255126529

Some hummingbird females look like males to evade harassment

 eurekalert.org/news-releases/926477

    

[Ornithology • 2019] Total-Evidence Framework Reveals Complex Morphological Evolution in Nightbirds (Strisores)

in Chen, White, Benson, et al., 2019.

  

DOI: 10.3390/d11090143 

  albertonykus.blogspot.com  twitter.com/albertonykus 

Abstract

 Strisores is a clade of neoavian birds that include diurnal aerial specialists such as swifts and hummingbirds, as well as several predominantly nocturnal lineages such as nightjars and potoos. Despite the use of genome-scale molecular datasets, the phylogenetic interrelationships among major strisorean groups remain controversial. Given the availability of next-generation sequence data for Strisores and the clade’s rich fossil record, we reassessed the phylogeny of Strisores by incorporating a large-scale sequence dataset with anatomical data from living and fossil strisoreans within a Bayesian total-evidence framework. Combined analyses of molecular and morphological data resulted in a phylogenetic topology for Strisores that is congruent with the findings of two recent molecular phylogenomic studies, supporting nightjars (Caprimulgidae) as the extant sister group of the remainder of Strisores. This total-evidence framework allowed us to identify morphological synapomorphies for strisorean clades previously recovered using molecular-only datasets. However, a combined analysis of molecular and morphological data highlighted strong signal conflict between sequence and anatomical data in Strisores. Furthermore, simultaneous analysis of molecular and morphological data recovered differing placements for some fossil taxa compared with analyses of morphological data under a molecular scaffold, highlighting the importance of analytical decisions when conducting morphological phylogenetic analyses of taxa with molecular phylogenetic data. We suggest that multiple strisorean lineages have experienced convergent evolution across the skeleton, obfuscating the phylogenetic position of certain fossils, and that many distinctive specializations of strisorean subclades were acquired early in their evolutionary history. Despite this apparent complexity in the evolutionary history of Strisores, our results provide fossil support for aerial foraging as the ancestral ecological strategy of Strisores, as implied by recent phylogenetic topologies derived from molecular data.

Keywords: Strisores; avian; phylogeny; evolution; morphology; total-evidence

Conclusions: 

The present work represents one of the most comprehensive studies on strisorean phylogeny to date in terms of character sampling, combining a genome-scale molecular dataset and a large sample of fossil taxa in an attempt to resolve the internal relationships of this enigmatic clade of birds. The preferred topology found in this study places Caprimulgidae, (Steatornithidae + Nyctibiidae), and Podargidae as successively closer relatives of Daedalornithes, which is congruent with the results of some other recent phylogenomic analyses of Strisores. We also identified possible morphological synapomorphies that unite strisorean clades recovered using molecular data and potential fossil evidence that may support aerial foraging as the ancestral ecology of Strisores, as implied by molecular topologies. Contrary to expectations, however, combining morphological and molecular datasets did not increase confidence in any specific phylogenetic topology, despite the inclusion of a phylogenetically diverse range of well-known fossil taxa. We attribute this surprising result to high levels of morphological homoplasy in Strisores, early morphological diversification possibly obscuring ancestral morphologies in known fossil strisoreans, and the relatively small size of existing morphological matrices pertaining to strisoreans. Further refinement of phylogenomic methods may also advance future estimates of strisorean phylogeny. Our findings suggest that improved understanding of morphological evolution in strisoreans will be contingent on the discovery of even older fossil taxa that retain more plesiomorphic morphologies, as well as more comprehensive character sampling in morphological datasets.

Albert Chen, Noor D. White, Roger B.J. Benson, Michael J. Braun and Daniel J. Field. 2019. Total-Evidence Framework Reveals Complex Morphological Evolution in Nightbirds (Strisores). Diversity. 11(9); 143. DOI: 10.3390/d11090143  

 albertonykus.blogspot.com/2019/08/shining-light-on-nightbird-evolution-my.html

 twitter.com/albertonykus/status/1167363784660242438

 twitter.com/albertonykus/status/1167875670615085057

[Ornithology • 2017] Heliangelus zusii • An Extinct Hummingbird Species That Never Was: A Cautionary Tale About Sampling Issues in Molecular Phylogenetics

Phylogenetic relationships among species and populations of Aglaiocercus, Taphrolesbia, the Rogitama hybrid hummingbird, and Heliangelus zusii based on sequences of the ND2 mitochondrial gene. Strongly supported nodes (0.95 Bayesian posterior probability, 80% maximum-likelihood bootstrap) are indicated with black dots. Although nodal support for deep branches is low, note that both the Rogitama bird and H. zusii have haplotypes closely allied to those of A. kingii from the Eastern Andes of Colombia, indicating they are both hybrids sharing A. kingii as female parent.

in Perez-Eman, Ferreira, Gutierrez-Pinto, et al., 2017.

 DOI:  10.1101/149898  

Illustrations courtesy of Lynx Edicions; Handbook of the Birds of the World, Vol. 15, 1999.

Abstract

The Bogota Sunangel (Heliangelus zusii) was described based on a historical specimen lacking locality data as a striking - and potentially extinct - new species of hummingbird more than two decades ago. However, it was considered a dubious taxon by some researchers until a molecular study with strong species-level taxon sampling revealed its phylogenetic affinities and validated its status as a distinct species. We reanalysed existing mitochondrial DNA data together with a new data set sampling multiple populations of the Long-tailed Sylph (Aglaiocercus kingii), a species broadly distributed in the Andes of South America. In contrast to previous work, we found that H. zusii shares a haplotype with specimens of A. kingii from the Eastern Cordillera of Colombia, which is phylogenetically nested within a clade formed by populations of A. kingii from the Colombian Andes. These results suggest that H. zusii is not a distinct species, but is most likely the result of hybridization between a female A. kingii and a male of another hummingbird species. These findings highlight the importance of thorough taxonomic and geographic sampling when assessing the likelihood of hybrid origin of an organism, particularly in cases potentially involving wide-ranging species in areas where deep phylogeographic structure is likely.

Keywords: Aglaiocercus, geographic sampling, Heliangelus zusii, hybridization, phylogeography.

Figure 1. (A) Geographic ranges of Aglaiocercus kingii, A. coelestis, and Taphrolesbia griseiventris in northern South America (polygons), and geographic provenance of specimens of these species and of the Rogitama hybrid hummingbird included in molecular phylogenetic analyses (dots and star).

Figure 1. (A) Geographic ranges of Aglaiocercus kingii, A. coelestis, and Taphrolesbia griseiventris in northern South America (polygons), and geographic provenance of specimens of these species and of the Rogitama hybrid hummingbird included in molecular phylogenetic analyses (dots and star).
(B) Phylogenetic relationships among species and populations of Aglaiocercus, Taphrolesbia, the Rogitama hybrid hummingbird, and Heliangelus zusii based on sequences of the ND2 mitochondrial gene. Strongly supported nodes (0.95 Bayesian posterior probability, 80% maximum-likelihood bootstrap) are indicated with black dots. Although nodal support for deep branches is low, note that both the Rogitama bird and H. zusii have haplotypes closely allied to those of A. kingii from the Eastern Andes of Colombia, indicating they are both hybrids sharing A. kingii as female parent.

 Illustrations courtesy of Lynx Edicions; Handbook of the Birds of the World, Vol. 15, 1999.

Jorge L. Perez-Eman, Jhoniel Perdigon Ferreira, Natalia Gutierrez-Pinto, Andres M. Cuervo, Laura N. Cespedes, Christopher C. Witt and Carlos Daniel Cadena. 2017. An Extinct Hummingbird Species That Never Was: A Cautionary Tale About Sampling Issues in Molecular Phylogenetics. bioRxiv. DOI:  10.1101/149898