scholarly journals Macroevolutionary dynamics in environmental space and the latitudinal diversity gradient in New World birds

2006 ◽  
Vol 274 (1606) ◽  
pp. 43-52 ◽  
Author(s):  
José Alexandre Felizola Diniz-Filho ◽  
Thiago Fernando L.V.B Rangel ◽  
Luis Mauricio Bini ◽  
Bradford A Hawkins
Keyword(s):  
Adaptive Radiation ◽  
New World ◽  
Bird Species ◽  
Climatic Effects ◽  
Evolutionary Mechanisms ◽  
Diversification Rates ◽  
Model Based ◽  
Environmental Space ◽  
Family Level ◽  
The Tropics

Correlations between species richness and climate suggest non-random occupation of environmental space and niche evolution through time. However, the evolutionary mechanisms involved remain unresolved. Here, we partition the occupation of environmental space into intra- and inter-clade components to differentiate a model based on pure conservation of ancestral niches with higher diversification rates in the tropics, and an adaptive radiation model based on shifts in adaptive peaks at the family level allowing occupation of temperate regions. We examined these mechanisms using within- and among-family skewness components based on centroids of 3560 New World bird species across four environmental variables. We found that the accumulation of species in the tropics is a result of both processes. The components of adaptive radiation have family level skewness of species' distributions strongly structured in space, but not phylogenetically, according to the integrated analyses of spatial filters and phylogenetic eigenvectors. Moreover, stronger radiation components were found for energy variables, which are often used to argue for direct climatic effects on diversity. Thus, the correspondence between diversity and climate may be due to the conservation of ancestral tropical niches coupled with repeated broad shifts in adaptive peaks during birds' evolutionary history more than by higher diversification rates driven by more energy in the tropics.

scholarly journals Exploring diversification drivers in golden orbweavers

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Eva Turk ◽  
Simona Kralj-Fišer ◽  
Matjaž Kuntner
Keyword(s):  
Environmental Factors ◽  
Sexual Size Dimorphism ◽  
Male Body ◽  
Diversification Rates ◽  
Size Dimorphism ◽  
Extinction Rates ◽  
Intermediate Phenotypes ◽  
Dispersal Propensity ◽  
The Tropics ◽  
Class Models

AbstractHeterogeneity in species diversity is driven by the dynamics of speciation and extinction, potentially influenced by organismal and environmental factors. Here, we explore macroevolutionary trends on a phylogeny of golden orbweavers (spider family Nephilidae). Our initial inference detects heterogeneity in speciation and extinction, with accelerated extinction rates in the extremely sexually size dimorphic Nephila and accelerated speciation in Herennia, a lineage defined by highly derived, arboricolous webs, and pronounced island endemism. We evaluate potential drivers of this heterogeneity that relate to organisms and their environment. Primarily, we test two continuous organismal factors for correlation with diversification in nephilids: phenotypic extremeness (female and male body length, and sexual size dimorphism as their ratio) and dispersal propensity (through range sizes as a proxy). We predict a bell-shaped relationship between factor values and speciation, with intermediate phenotypes exhibiting highest diversification rates. Analyses using SSE-class models fail to support our two predictions, suggesting that phenotypic extremeness and dispersal propensity cannot explain patterns of nephilid diversification. Furthermore, two environmental factors (tropical versus subtropical and island versus continental species distribution) indicate only marginal support for higher speciation in the tropics. Although our results may be affected by methodological limitations imposed by a relatively small phylogeny, it seems that the tested organismal and environmental factors play little to no role in nephilid diversification. In the phylogeny of golden orbweavers, the recent hypothesis of universal diversification dynamics may be the simplest explanation of macroevolutionary patterns.

scholarly journals Is Sexual Conflict a Driver of Speciation? A Case Study With a Tribe of Brush-footed Butterflies

2020 ◽  
Author(s):  
Ana Paula S Carvalho ◽  
Ryan A St Laurent ◽  
Emmanuel F A Toussaint ◽  
Caroline Storer ◽  
Kelly M Dexter ◽  
...  
Keyword(s):  
Sexual Conflict ◽  
Abiotic Factors ◽  
Evolutionary Mechanisms ◽  
Diversification Rates ◽  
Exon Capture ◽  
Key Driver ◽  
Underlying Mechanisms ◽  
Analytical Approaches ◽  
Acting In Concert

Abstract Understanding the evolutionary mechanisms governing the uneven distribution of species richness across the tree of life is a great challenge in biology. Scientists have long argued that sexual conflict is a key driver of speciation. This hypothesis, however, has been highly debated in light of empirical evidence. Recent advances in the study of macroevolution make it possible to test this hypothesis with more data and increased accuracy. In the present study, we use phylogenomics combined with four different diversification rate analytical approaches to test whether sexual conflict is a driver of speciation in brush-footed butterflies of the tribe Acraeini. The presence of a sphragis, an external mating plug found in most species among Acraeini, was used as a proxy for sexual conflict. Diversification analyses statistically rejected the hypothesis that sexual conflict is associated with shifts in diversification rates in Acraeini. This result contrasts with earlier studies and suggests that the underlying mechanisms driving diversification are more complex than previously considered. In the case of butterflies, natural history traits acting in concert with abiotic factors possibly play a stronger role in triggering speciation than does sexual conflict. [Acraeini butterflies; arms race; exon capture phylogenomics; Lepidoptera macroevolution; sexual selection; sphragis.]

scholarly journals Evaluating the role of contracting and expanding rainforest in initiating cycles of speciation across the Isthmus of Panama

2012 ◽  
Vol 279 (1742) ◽  
pp. 3520-3526 ◽  
Author(s):  
Brian Tilston Smith ◽  
Amei Amei ◽  
John Klicka
Keyword(s):  
Bird Species ◽  
Tropical Regions ◽  
Isthmus Of Panama ◽  
Species Pairs ◽  
The Matrix ◽  
High Species Richness ◽  
The Rich ◽  
The Tropics ◽  
The Impact

Climatic and geological changes across time are presumed to have shaped the rich biodiversity of tropical regions. However, the impact climatic drying and subsequent tropical rainforest contraction had on speciation has been controversial because of inconsistent palaeoecological and genetic data. Despite the strong interest in examining the role of climatic change on speciation in the Neotropics there has been few comparative studies, particularly, those that include non-rainforest taxa. We used bird species that inhabit humid or dry habitats that dispersed across the Panamanian Isthmus to characterize temporal and spatial patterns of speciation across this barrier. Here, we show that these two assemblages of birds exhibit temporally different speciation time patterns that supports multiple cycles of speciation. Evidence for these cycles is further corroborated by the finding that both assemblages consist of ‘young’ and ‘old’ species, despite dry habitat species pairs being geographically more distant than pairs of humid habitat species. The matrix of humid and dry habitats in the tropics not only allows for the maintenance of high species richness, but additionally this study suggests that these environments may have promoted speciation. We conclude that differentially expanding and contracting distributions of dry and humid habitats was probably an important contributor to speciation in the tropics.

scholarly journals Losses of female song with changes from tropical to temperate breeding in the New World blackbirds

2009 ◽  
Vol 276 (1664) ◽  
pp. 1971-1980 ◽  
Author(s):  
J. Jordan Price ◽  
Scott M. Lanyon ◽  
Kevin E. Omland
Keyword(s):  
Sexual Selection ◽  
New World ◽  
Female Song ◽  
Complex Song ◽  
Evolutionary Changes ◽  
Apparent Relationship ◽  
Song Production ◽  
Selection For ◽  
The Tropics

Birds in which both sexes produce complex songs are thought to be more common in the tropics than in temperate areas, where typically only males sing. Yet the role of phylogeny in this apparent relationship between female song and latitude has never been examined. Here, we reconstruct evolutionary changes in female song and breeding latitude in the New World blackbirds (Icteridae), a family with both temperate and tropical representatives. We provide strong evidence that members of this group have moved repeatedly from tropical to temperate breeding ranges and, furthermore, that these range shifts were associated with losses of female song more often than expected by chance. This historical perspective suggests that male-biased song production in many temperate species is the result not of sexual selection for complex song in males but of selection against such songs in females. Our results provide new insights into the differences we see today between tropical and temperate songbirds, and suggest that the role of sexual selection in the evolution of bird song might not be as simple as we think.

scholarly journals Tip rates, phylogenies, and diversification: what are we estimating, and how good are the estimates?

2018 ◽  
Author(s):  
Pascal O. Title ◽  
Daniel L. Rabosky
Keyword(s):  
Diversification Rate ◽  
Rate Variation ◽  
Terminal Branch ◽  
List Type ◽  
Large Set ◽  
Extinction Rate ◽  
Diversification Rates ◽  
Speciation Rate ◽  
Model Based ◽  
Model Free

AbstractSpecies-specific diversification rates, or “tip rates”, can be computed quickly from phylogenies and are widely used to study diversification rate variation in relation to geography, ecology, and phenotypes. These tip rates provide a number of theoretical and practical advantages, such as the relaxation of assumptions of rate homogeneity in trait-dependent diversification studies. However, there is substantial confusion in the literature regarding whether these metrics estimate speciation or net diversification rates. Additionally, no study has yet compared the relative performance and accuracy of tip rate metrics across simulated diversification scenarios.We compared the statistical performance of three model-free rate metrics (inverse terminal branch lengths; node density metric; DR statistic) and a model-based approach (BAMM). We applied each method to a large set of simulated phylogenies that had been generated under different diversification processes; scenarios included multi-regime time-constant and diversity-dependent trees, as well as trees where the rate of speciation evolves under a diffusion process. We summarized performance in relation to the type of rate variation, the magnitude of rate heterogeneity and rate regime size. We also compared the ability of the metrics to estimate both speciation and net diversification rates.We show decisively that model-free tip rate metrics provide a better estimate of the rate of speciation than of net diversification. Error in net diversification rate estimates increases as a function of the relative extinction rate. In contrast, error in speciation rate estimates is low and relatively insensitive to extinction. Overall, and in particular when relative extinction was high, BAMM inferred the most accurate tip rates and exhibited lower error than non-model-based approaches. DR was highly correlated with true speciation rates but exhibited high error variance, and was the best metric for very small rate regimes.We found that, of the metrics tested, DR and BAMM are the most useful metrics for studying speciation rate dynamics and trait-dependent diversification. Although BAMM was more accurate than DR overall, the two approaches have complementary strengths. Because tip rate metrics are more reliable estimators of speciation rate, we recommend that empirical studies using these metrics exercise caution when drawing biological interpretations in any situation where the distinction between speciation and net diversification is important.

scholarly journals The Dynamics of Bird Diversity in the New World

2020 ◽  
Vol 69 (6) ◽  
pp. 1180-1199 ◽  
Author(s):  
Antonin Machac
Keyword(s):  
Species Richness ◽  
New World ◽  
Dominant Role ◽  
Bird Diversity ◽  
Biodiversity Hotspots ◽  
Relative Importance ◽  
Diversification Rates ◽  
The Andes ◽  
The Rich ◽  
Over Time

Abstract Three prominent explanations have been proposed to explain the dramatic differences in species richness across regions and elevations, (i) time for speciation, (ii) diversification rates, and (iii) ecological limits. But the relative importance of these explanations and, especially, their interplay and possible synthesis remain largely elusive. Integrating diversification analyses, null models, and geographic information systems, I study avian richness across regions and elevations of the New World. My results reveal that even though the three explanations are differentially important (with ecological limits playing the dominant role), each contributes uniquely to the formation of richness gradients. Further, my results reveal the likely interplay between the explanations. They indicate that ecological limits hinder the diversification process, such that the accumulation of species within a region gradually slows down over time. Yet, it does not seem to converge toward a hard ceiling on regional richness. Instead, species-rich regions show suppressed, but continued, diversification, coupled with signatures of possible competition (esp. Neotropical lowlands). Conversely, species-poor, newly-colonized regions show fast diversification and weak to no signs of competition (esp. Nearctic highlands). These results held across five families of birds, across grid cells, biomes, and elevations. Together, my findings begin to illuminate the rich, yet highly consistent, interplay of the mechanisms that together shape richness gradients in the New World, including the most species-rich biodiversity hotspots on the planet, the Andes and the Amazon. [Biogeography; community; competition; macroevolution; phylogenetics; richness gradient.]

scholarly journals Niche-tracking migrants and niche-switching residents: evolution of climatic niches in New World warblers (Parulidae)

2016 ◽  
Vol 283 (1824) ◽  
pp. 20152458 ◽  
Author(s):  
Camila Gómez ◽  
Elkin A. Tenorio ◽  
Paola Montoya ◽  
Carlos Daniel Cadena
Keyword(s):  
New World ◽  
Niche Overlap ◽  
Climatic Conditions ◽  
Tropical Species ◽  
Migratory Behaviour ◽  
Niche Evolution ◽  
Climatic Niche ◽  
Niche Dynamics ◽  
Patterns And Processes ◽  
The Tropics

Differences in life-history traits between tropical and temperate lineages are often attributed to differences in their climatic niche dynamics. For example, the more frequent appearance of migratory behaviour in temperate-breeding species than in species originally breeding in the tropics is believed to have resulted partly from tropical climatic stability and niche conservatism constraining tropical species from shifting their ranges. However, little is known about the patterns and processes underlying climatic niche evolution in migrant and resident animals. We evaluated the evolution of overlap in climatic niches between seasons and its relationship to migratory behaviour in the Parulidae, a family of New World passerine birds. We used ordination methods to measure seasonal niche overlap and niche breadth of 54 resident and 49 migrant species and used phylogenetic comparative methods to assess patterns of climatic niche evolution. We found that despite travelling thousands of kilometres, migrants tracked climatic conditions across the year to a greater extent than tropical residents. Migrant species had wider niches than resident species, although residents as a group occupied a wider climatic space and niches of migrants and residents overlapped extensively. Neither breeding latitude nor migratory distance explained variation among species in climatic niche overlap between seasons. Our findings support the notion that tropical species have narrower niches than temperate-breeders, but does not necessarily constrain their ability to shift or expand their geographical ranges and become migratory. Overall, the tropics may have been historically less likely to experience the suite of components that generate strong selection pressures for the evolution of migratory behaviour.

scholarly journals Factors affecting migratory bird routes over the Gulf of Mexico

1994 ◽  
Vol 4 (2-3) ◽  
pp. 251-262 ◽  
Author(s):  
John H. Rappole ◽  
Mario A. Ramos
Keyword(s):  
Gulf Of Mexico ◽  
Central America ◽  
Gulf Coast ◽  
Bird Species ◽  
Migratory Bird ◽  
Factors Affecting ◽  
Migratory Flight ◽  
Prevailing Wind Direction ◽  
Northern Gulf Coast ◽  
The Tropics

SummaryOver half of the 332 migratory bird species that breed in North America and winter in the tropics are affected by the obstacle to migratory flight presented by the Gulf of Mexico. Landbird migration in the vicinity of the Gulf is considered from an historical perspective, and in light of netting and observational data from the western Gulf coast. A trans-Gulf crossing from the northern Gulf coast to, or over, Yucatan is the most commonly followed fall route for eastern Nearctic migrants that winter in Central America. The spring route for these species is different, involving a more westerly trans–Gulf course for some individuals, and a circum–Gulf route for others. Prevailing wind direction and the probability of meeting turbulence over the Gulf are suggested as the main selective factors affecting route form for Gulf–area migrants.

Simulating the climatic effects on vegetation: approaches, issues and challenges

2008 ◽  
Vol 32 (5) ◽  
pp. 543-556 ◽  
Author(s):  
Guoping Tang ◽  
Patrick J. Bartlein
Keyword(s):  
Analytical Data ◽  
Terrestrial Vegetation ◽  
Climatic Effects ◽  
Model Based ◽  
Vegetation Modelling ◽  
Vegetation Models ◽  
Data Improvement ◽  
Analytical Approaches

Vegetation modelling has been viewed as a major approach for examining the dynamics of vegetation under climatic change. However, the characterization of uncertainty of model results is still a key issue. In order to improve future model-based research, it is important to synthesize the current approaches and the issues that arise in vegetation modelling and to propose potential strategies for improving model-based research. This study first reviews the progress of vegetation models from static-equilibrium to transient-dynamic and to current coupled multi-objective vegetation models. Then, the four main sources leading to the uncertainty of model results are described, including (1) factors related to vegetation models (their structure, assumption and parameterization), (2) the data used to run a model, (3) the approaches used to validate model results, and (4) the spatiotemporal scaling issues involved in vegetation modelling. Finally, four strategies are proposed for improving future model-based research. These include improvements in the model structure and parameterization, enhancement of the quality of analytical data, improvement of the analytical approaches, and continued development of coupled dynamic vegetation models. Using a literature synthesis, this study provides researchers with a general guidance on applying vegetation models for simulating the effects of climatic variations on terrestrial vegetation.

TESTING FOR LATITUDINAL BIAS IN DIVERSIFICATION RATES: AN EXAMPLE USING NEW WORLD BIRDS

Ecology ◽  
2005 ◽  
Vol 86 (9) ◽  
pp. 2278-2287 ◽  
Author(s):  
Marcel Cardillo ◽  
C. David L. Orme ◽  
Ian P. F. Owens
Keyword(s):  
New World ◽  
Diversification Rates ◽  
New World Birds
Sign in / Sign up

Export Citation Format

Share Document