The radiation continuum and the evolution of frog diversity.

Most of life's vast diversity of species and phenotypes is often attributed to adaptive radiation. Yet its contribution to species and phenotypic diversity of a major group has not been examined. Two key questions remain unresolved.

Bridging Performance and Adaptive Landscapes to Understand Long-Term Functional Evolution.

AbstractUnderstanding functional adaptation demands an integrative framework that captures the complex interactions between form, function, ecology, and evolutionary processes. In this review, we discuss how to integrate the following two distinct approaches to better understand functional evolution: (1) the adaptive landscape approach (ALA), aimed at finding adaptive peaks for different ecologies, and (2) the performance landscape approach (PLA), aimed at finding performance peaks for different ecologies. We focus on the Ornstein-Uhlenbeck process as the evolutionary model for the ALA and on biomechanical modeling to estimate performance for the PLA.

A Cautionary Note on "A Cautionary Note on the Use of Ornstein Uhlenbeck Models in Macroevolutionary Studies".

Models based on the Ornstein-Uhlenbeck process have become standard for the comparative study of adaptation. Cooper et al. (2016) have cast doubt on this practice by claiming statistical problems with fitting Ornstein-Uhlenbeck models to comparative data.

Redefining Possible: Combining Phylogenomic and Supersparse Data in Frogs.

The data available for reconstructing molecular phylogenies have become wildly disparate. Phylogenomic studies can generate data for thousands of genetic markers for dozens of species, but for hundreds of other taxa, data may be available from only a few genes. Can these two types of data be integrated to combine the advantages of both, addressing the relationships of hundreds of species with thousands of genes? Here, we show that this is possible, using data from frogs.

Ecology, sexual dimorphism, and jumping evolution in anurans.

Sexual dimorphism (SD) is a common feature of animals, and selection for sexually dimorphic traits may affect both functional morphological traits and organismal performance. Trait evolution through natural selection can also vary across environments. However, whether the evolution of organismal performance is distinct between the sexes is rarely tested in a phylogenetic comparative context.

Phylogenetic analysis of adaptation in comparative physiology and biomechanics: overview and a case study of thermal physiology in treefrogs.

Comparative phylogenetic studies of adaptation are uncommon in biomechanics and physiology. Such studies require data collection from many species, a challenge when this is experimentally intensive. Moreover, researchers struggle to employ the most biologically appropriate phylogenetic tools for identifying adaptive evolution.

Improving inference and avoiding overinterpretation of hidden-state diversification models: Specialized plant breeding has no effect on diversification in frogs.

The hidden-state speciation and extinction (HiSSE) model helps avoid spurious results when testing whether a character affects diversification rates. However, care must be taken to optimally analyze models and interpret results. Recently, Tonini et al.

Disturbed habitats locally reduce the signal of deep evolutionary history in functional traits of plants.

The functioning of present ecosystems reflects deep evolutionary history of locally cooccurring species if their functional traits show high phylogenetic signal (PS). However, we do not understand what drives local PS. We hypothesize that local PS is high in undisturbed and stressful habitats, either due to ongoing local assembly of species that maintained ancestral traits, or to past evolutionary maintenance of ancestral traits within habitat species-pools, or to both.

Testing for adaptive radiation: A new approach applied to Madagascar frogs.

Adaptive radiation is a key topic at the intersection of ecology and evolutionary biology. Yet the definition and identification of adaptive radiation both remain contentious. Here, we introduce a new approach for identifying adaptive radiations that combines key aspects of two widely used definitions.

Interspecific variation in bristle number on forewings of tiny insects does not influence clap-and-fling aerodynamics.

Miniature insects must overcome significant viscous resistance in order to fly. They typically possess wings with long bristles on the fringes and use a clap-and-fling mechanism to augment lift. These unique solutions to the extreme conditions of flight at tiny sizes (<2 mm body length) suggest that natural selection has optimized wing design for better aerodynamic performance.

What Determines the Distinct Morphology of Species with a Particular Ecology? The Roles of Many-to-One Mapping and Trade-Offs in the Evolution of Frog Ecomorphology and Performance.

Organisms inhabiting a specific environment often have distinct morphology, but the factors that affect this fit are unclear when multiple morphological traits affect performance in multiple behaviors. Does the realized morphology of a species reflect a compromise in performance among behaviors (i.e.

The relationship between habitat use and body shape in geckos.

Geckos are a highly diverse group of lizards, with more than 1,700 species that exhibit a wide range of behaviors, ecologies, and sizes. However, no study has examined links between habitat use and body shape in pad-bearing geckos. We set out to answer a basic question using a data set of pad-bearing geckos (112 species, 103 pad-bearing, 9 padless, 42 genera): Do geckos that occur in different habitats also differ in body shape? Overall, we found that body shape was surprisingly similar among our sample of pad-bearing species, with the exception of the genus Uroplatus, which was clearly distinct from other geckos due to its depressed body and long limbs.

Diversification rates are more strongly related to microhabitat than climate in squamate reptiles (lizards and snakes).

Patterns of species richness among clades can be directly explained by the ages of clades or their rates of diversification. The factors that most strongly influence diversification rates remain highly uncertain, since most studies typically consider only a single predictor variable. Here, we explore the relative impacts of macroclimate (i.

Microhabitat and Climatic Niche Change Explain Patterns of Diversification among Frog Families.

A major goal of ecology and evolutionary biology is to explain patterns of species richness among clades. Differences in rates of net diversification (speciation minus extinction over time) may often explain these patterns, but the factors that drive variation in diversification rates remain uncertain. Three important candidates are climatic niche position (e.

Testing Convergence Versus History: Convergence Dominates Phenotypic Evolution for over 150 Million Years in Frogs.

Striking evolutionary convergence can lead to similar sets of species in different locations, such as in cichlid fishes and Anolis lizards, and suggests that evolution can be repeatable and predictable across clades. Yet, most examples of convergence involve relatively small temporal and/or spatial scales. Some authors have speculated that at larger scales (e.

Evolutionary conservatism and convergence both lead to striking similarity in ecology, morphology and performance across continents in frogs.

Many clades contain ecologically and phenotypically similar species across continents, yet the processes generating this similarity are largely unstudied, leaving fundamental questions unanswered. Is similarity in morphology and performance across assemblages caused by evolutionary convergence or by biogeographic dispersal of evolutionarily conserved ecotypes? Does convergence to new ecological conditions erase evidence of past adaptation? Here, we analyse ecology, morphology and performance in frog assemblages from three continents (Asia, Australia and South America), assessing the importance of dispersal and convergent evolution in explaining similarity across regions. We find three striking results.

Phylogenetic origins of local-scale diversity patterns and the causes of Amazonian megadiversity.

What explains the striking variation in local species richness across the globe and the remarkable diversity of rainforest sites in Amazonia? Here, we apply a novel phylogenetic approach to these questions, using treefrogs (Hylidae) as a model system. Hylids show dramatic variation in local richness globally and incredible local diversity in Amazonia. We find that variation in local richness is not explained primarily by climatic factors, rates of diversification (speciation and extinction) nor morphological variation.

An expanded phylogeny of treefrogs (Hylidae) based on nuclear and mitochondrial sequence data.

The treefrogs (Hylidae) make up one of the most species-rich families of amphibians. With 885 species currently described, they contain >13% of all amphibian species. In recent years, there has been considerable progress in resolving hylid phylogeny.

Community assembly through evolutionary diversification and dispersal in Middle American treefrogs.

How are ecologically diverse organisms added to local assemblages to create the community structure we see today? In general, within a given region or community, a given trait (character state) may either evolve in situ or be added through dispersal after having evolved elsewhere. Here, we develop simple metrics to quantify the relative importance of these processes and then apply them to a case study in Middle American treefrogs. We examined two ecologically important characters (larval habitat and body size) among 39 communities, using phylogenetic and ecological information from 278 species both inside and outside the region.

Phylogenetic evidence for competitively driven divergence: body-size evolution in Caribbean treefrogs (Hylidae: Osteopilus).

Understanding the role of competition in explaining phenotypic diversity is a challenging problem, given that the most divergent species may no longer compete today. However, convergent evolution of extreme body sizes across communities may offer evidence of past competition. For example, many treefrog assemblages around the world have convergently evolved species with very large and small body sizes.

Evolutionary and ecological causes of the latitudinal diversity gradient in hylid frogs: treefrog trees unearth the roots of high tropical diversity.

Why are there more species in the tropics than in temperate regions? In recent years, this long-standing question has been addressed primarily by seeking environmental correlates of diversity. But to understand the ultimate causes of diversity patterns, we must also examine the evolutionary and biogeographic processes that directly change species numbers (i.e.