Body size and latitudinal gradients in regional diversity of New World birds

AbstractAdaptations can be thought of as evolutionary technologies which allow an organism to exploit environments. Among convergent taxa, adaptations may be largely equivalent with the taxa operating in a similar set of environmental conditions, divergent with the taxa operating in different sets of environmental conditions, or superior with one taxon operating within an extended range of environmental conditions than the other. With this framework in mind, we sought to characterize the adaptations of two convergent nectarivorous bird families, the New World hummingbirds (Trochilidae) and Old World sunbirds (Nectariniidae), by comparing their biogeography. Looking at their elevational and latitudinal gradients, hummingbirds not only extend into but also maintain species richness in more extreme environments. We suspect that hummingbirds have a superior key adaptation that sunbirds lack, namely a musculoskeletal architecture that allows for hovering. Through biogeographic comparisons, we have been able to assess and understand adaptations as evolutionary technologies among two convergent bird families, a process that should work for most taxa.

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Latitudinal body-mass trends in Oligo-Miocene mammals

Paleobiology ◽

10.1017/pab.2016.13 ◽

2016 ◽

Vol 42 (4) ◽

pp. 643-658

Author(s):

John D. Orcutt ◽

Samantha S. B. Hopkins

Keyword(s):

Body Size ◽

Body Mass ◽

Regional Scale ◽

Latitudinal Gradients ◽

Bergmann’S Rule ◽

Strongly Correlated ◽

Bergmann's Rule ◽

Deep Time ◽

Causal Factors ◽

Primary Driver

AbstractPaleecological data allow not only the study of trends along deep-time chronological transects but can also be used to reconstruct ecological gradients through time, which can help identify causal factors that may be strongly correlated in modern ecosystems. We have applied such an analysis to Bergmann’s rule, which posits a causal relationship between temperature and body size in mammals. Bergmann’s rule predicts that latitudinal gradients should exist during any interval of time, with larger taxa toward the poles and smaller taxa toward the equator. It also predicts that the strength of these gradients should vary with time, becoming weaker during warmer periods and stronger during colder conditions. We tested these predictions by reconstructing body-mass trends within canid and equid genera at different intervals of the Oligo-Miocene along the West Coast of North America. To allow for comparisons with modern taxa, body mass was reconstructed along the same transect for modernCanisandOdocoileus. Of the 17 fossil genera analyzed, only two showed the expected positive relationship with latitude, nor was there consistent evidence for a relationship between paleotemperature and body mass. Likewise, the strength of body-size gradients does not change predictably with climate through time. The evidence for clear gradients is ambiguous even in the modern genera analyzed. These results suggest that, counter to Bergmann’s rule, temperature alone is not a primary driver of body size and underscore the importance of regional-scale paleoecological analyses in identifying such drivers.

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Exquisitely Preserved Fossil Snakes of Messel: Insight into the Evolution, Biogeography, Habitat Preferences and Sensory Ecology of Early Boas

Diversity ◽

10.3390/d12030100 ◽

2020 ◽

Vol 12 (3) ◽

pp. 100 ◽

Cited By ~ 2

Author(s):

Agustín Scanferla ◽

Krister T. Smith

Keyword(s):

Body Size ◽

New World ◽

Middle Eocene ◽

Habitat Preferences ◽

Sensory Ecology ◽

Morphological Diversity ◽

Predator Prey ◽

Upper Jaw ◽

Spectrum Evaluation ◽

Insight Into

Our knowledge of early evolution of snakes is improving, but all that we can infer about the evolution of modern clades of snakes such as boas (Booidea) is still based on isolated bones. Here, we resolve the phylogenetic relationships of Eoconstrictor fischeri comb. nov. and other booids from the early-middle Eocene of Messel (Germany), the best-known fossil snake assemblage yet discovered. Our combined analyses demonstrate an affinity of Eoconstrictor with Neotropical boas, thus entailing a South America-to-Europe dispersal event. Other booid species from Messel are related to different New World clades, reinforcing the cosmopolitan nature of the Messel booid fauna. Our analyses indicate that Eoconstrictor was a terrestrial, medium- to large-bodied snake that bore labial pit organs in the upper jaw, the earliest evidence that the visual system in snakes incorporated the infrared spectrum. Evaluation of the known palaeobiology of Eoconstrictor provides no evidence that pit organs played a role in the predator–prey relations of this stem boid. At the same time, the morphological diversity of Messel booids reflects the occupation of several terrestrial macrohabitats, and even in the earliest booid community the relation between pit organs and body size is similar to that seen in booids today.

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Austral Migrants and the Evolution of Migration in New World Birds: Diet, Habitat, and Migration Revisited

The American Naturalist ◽

10.1086/286171 ◽

1998 ◽

Vol 152 (2) ◽

pp. 311-319 ◽

Cited By ~ 51

Author(s):

R. Terry Chesser ◽

Douglas J. Levey

Keyword(s):

New World ◽

New World Birds ◽

Evolution Of Migration ◽

And Migration

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Environmental and ecological factors mediate taxonomic composition and body size of polyplacophoran assemblages along the Peruvian Province

Scientific Reports ◽

10.1038/s41598-019-52395-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Christian M. Ibáñez ◽

Melany Waldisperg ◽

Felipe I. Torres ◽

Sergio A. Carrasco ◽

Javier Sellanes ◽

...

Keyword(s):

Body Size ◽

Species Composition ◽

Size Structure ◽

Environmental Gradients ◽

Ecological Factors ◽

Taxonomic Composition ◽

Latitudinal Gradients ◽

Size Segregation ◽

Biogeographic Patterns ◽

Diversity Gradient

Abstract Intertidal communities’ composition and diversity usually exhibit strong changes in relation to environmental gradients at different biogeographical scales. This study represents the first comprehensive diversity and composition description of polyplacophoran assemblages along the Peruvian Province (SE Pacific, 12°S–39°S), as a model system for ecological latitudinal gradients. A total of 4,775 chitons from 21 species were collected on twelve localities along the Peruvian Province. This sampling allowed us to quantitatively estimate the relative abundance of the species in this assemblage, and to test whether chitons conform to elementary predictions of major biogeographic patterns such as a latitudinal diversity gradient. We found that the species composition supported the division of the province into three ecoregional faunal groups (i.e. Humboldtian, Central Chile, and Araucanian). Though chiton diversity did not follow a clear latitudinal gradient, changes in species composition were dominated by smaller scale variability in salinity and temperature. Body size significantly differed by ecoregions and species, indicating latitudinal size-structure assamblages. In some localities body size ratios differed from a random assemblage, evidencing competition at local scale. Changes in composition between ecoregions influence body size structure, and their overlapping produce vertical size segregation, suggesting that competition coupled with environmental conditions structure these assemblages.

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Sexual Dimorphism, Mating System and Body Size in New World Blackbirds (Icterinae)

Evolution ◽

10.2307/2410020 ◽

1992 ◽

Vol 46 (6) ◽

pp. 1621 ◽

Cited By ~ 61

Author(s):

Michael S. Webster

Keyword(s):

Body Size ◽

Sexual Dimorphism ◽

Mating System ◽

New World

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The Lives and Deaths of Caged Birds: Transatlantic Voyages of Wild Creatures from the Americas to Spain, 1740s–1790s

Ethnohistory ◽

10.1215/00141801-8266470 ◽

2020 ◽

Vol 67 (3) ◽

pp. 481-501

Author(s):

Martha Few

Keyword(s):

Eighteenth Century ◽

Lived Experiences ◽

New World ◽

Material Objects ◽

Transatlantic Trade ◽

New World Birds

Abstract This essay focuses on New World birds caught up in the eighteenth-century transatlantic trade with other living wild creatures, destined for imperial metropoles. Manuscript sources describing this trade, written by political officials, ships’ captains, doctors, naturalists, animal caretakers, and inspectors who cataloged their arrival to Spanish ports, interacted with the animals, tried to keep them alive aboard the ship, and determined their ability to withstand further transport to their final destinations in Madrid and other cities in Spain. In the process, animals caged aboard ship for several weeks or more developed relationships with one another and with their human caretakers. Their lived experiences show the multiple and complicated ways in which individual captured birds and other creatures helped shape those shipboard environments, disrupting systemic human attempts to construct them as colonial animals who functioned solely as scientific or material objects in empire making.

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