scholarly journals Traits, trees and taxa: global dimensions of biodiversity in mammals

2012 ◽  
Vol 279 (1749) ◽  
pp. 4997-5003 ◽  
Author(s):  
Shan Huang ◽  
Patrick R. Stephens ◽  
John L. Gittleman
Keyword(s):  
Species Richness ◽  
Phylogenetic Diversity ◽  
Functional Trait ◽  
Global Scale ◽  
Conservation Value ◽  
Strongly Correlated ◽  
As Species ◽  
Trait Variance ◽  
Potential Losses ◽  
Functional Trait Diversity

Measures of biodiversity encompass variation along several dimensions such as species richness (SR), phylogenetic diversity (PD) and functional/trait diversity (TD). At the global scale, it is widely recognized that SR and PD are strongly correlated, but the extent to which either tends to capture variation in TD is unclear. Here, we assess relationships among PD, SR and TD for a number of traits both across clades and regional assemblages of mammals. We also contrast results using two different measures of TD, trait variance and a new measure we refer to as trait bin filling (the number of orders of magnitude of variation that contain at least one species). When TD is defined as trait variance, PD is a much stronger correlate of TD than SR across clades, consistent with hypotheses about the conservation value of PD. However, when TD is defined as bin filling, PD and SR show similar correlations with TD across clades and space. We also investigate potential losses of SR, PD and TD if species that are currently threatened were to go extinct, and find that threatened PD is often a similar predictor of threatened TD as SR.

Diversity components and assembly patterns of plant functional traits determine community spatial stability under resource gradients in a desert steppe

2016 ◽  
Vol 38 (5) ◽  
pp. 511 ◽  
Author(s):  
Zhao Na ◽  
Wang Zhengwen ◽  
Shao Xinqing ◽  
Wang Kun
Keyword(s):  
Species Richness ◽  
Functional Traits ◽  
Nutrient Availability ◽  
Functional Group ◽  
Group Composition ◽  
Functional Trait ◽  
Spatial Stability ◽  
Trait Diversity ◽  
The Relationship ◽  
Functional Trait Diversity

The diversity–stability relationship has been addressed and debated for decades, but how this relationship is affected by nutrient availability remains contentious. In the present study we assessed the effects of plant diversity, in terms of species richness, functional group composition and functional trait diversity, on the spatial stability of net primary productivity (NPP) following nitrogen and phosphorus application. In addition, we explored how functional traits at the species level contribute to the spatial stability of NPP. The results support the hypothesis that greater diversity leads to higher spatial stability. This relationship was highly dependent on soil nutrient availability, and increasing species richness or functional trait diversity significantly increased spatial variation of NPP under a high N fertilisation level. The effects of high mineral fertilisation rates may perhaps have masked the effects of plant diversity. Although species richness or functional trait diversity of the original and modified communities from which species with particular functional traits had been removed were significantly different, there were no differences in the coefficients of variation in the NPP of those communities. The lack of difference demonstrated that the relationship between spatial variability and biodiversity depended on the measure of diversity applied and that the functional group composition exerted a stronger effect than other diversity measures. Further analyses revealed that spatial stability of NPP was enhanced with increased diversity in vegetative plant height, rooting depth and the presence of legume, and diminished with diversity in the root system type and life cycle under some fertilisation treatments. The present study demonstrates that the relationship between biodiversity and ecosystem functioning is variable with different diversity, identity and environmental factors. Evaluating the contribution of particular traits to community stability will ultimately help us better understand the mechanisms underlying the diversity–stability relationship.

scholarly journals DETECTING PHYLODIVERSITY-DEPENDENT DIVERSIFICATION WITH A GENERAL PHYLOGENETIC INFERENCE FRAMEWORK

2021 ◽  
Author(s):  
Francisco Richter ◽  
Ernst C. Wit ◽  
Rampal S. Etienne ◽  
Thijs Janzen ◽  
Hanno Hildenbrandt
Keyword(s):  
Species Richness ◽  
Expectation Maximization ◽  
Phylogenetic Diversity ◽  
R Package ◽  
Inference Method ◽  
Likelihood Methods ◽  
Species Diversification ◽  
As Species ◽  
Monte Carlo Expectation Maximization ◽  
Phylogenetic Divergence

Diversity-dependent diversification models have been extensively used to study the effect of ecological limits and feedback of community structure on species diversification processes, such as speciation and extinction. Current diversity-dependent diversification models characterise ecological limits by carrying capacities for species richness. Such ecological limits have been justified by niche filling arguments: as species diversity increases, the number of available niches for diversification decreases. However, as species diversify they may diverge from one another phenotypically, which may open new niches for new species. Alternatively, this phenotypic divergence may not affect the species diversification process or even inhibit further diversification. Hence, it seems natural to explore the consequences of phylogenetic diversity-dependent (or phylodiversity-dependent) diversification. Current likelihood methods for estimating diversity-dependent diversification parameters cannot be used for this, as phylodiversity is continuously changing as time progresses and species form and become extinct. Here, we present a new method based on Monte Carlo Expectation-Maximization (MCEM), designed to perform statistical inference on a general class of species diversification models and implemented in the R package emphasis. We use the method to fit phylodiversity-dependent diversification models to 14 phylogenies, and compare the results to the fit of a richness-dependent diversification model. We find that in a number of phylogenies, phylogenetic divergence indeed spurs speciation even though species richness reduces it. Not only do we thus shine a new light on diversity-dependent diversification, we also argue that our inference framework can handle a large class of diversification models for which currently no inference method exists.

Estimating the effects of sampling biases on pterosaur diversity patterns: implications for hypotheses of bird/pterosaur competitive replacement

Paleobiology ◽  
2009 ◽  
Vol 35 (3) ◽  
pp. 432-446 ◽  
Author(s):  
Richard J. Butler ◽  
Paul M. Barrett ◽  
Stephen Nowbath ◽  
Paul Upchurch
Keyword(s):  
Species Richness ◽  
Fossil Record ◽  
Phylogenetic Diversity ◽  
Detailed Examination ◽  
Causal Mechanism ◽  
Strongly Correlated ◽  
Diversity Patterns ◽  
Ecological Radiation ◽  
Diversity Estimates

Pterosaurs were the first flying vertebrates and formed important components of terrestrial and marginal marine ecosystems during the Mesozoic. They became extinct during the latest Cretaceous (latest Maastrichtian), at, or near, the Cretaceous/Paleogene boundary, following an apparent decline in diversity in the Late Cretaceous. This reduction in species richness has been linked to the ecological radiation of birds in the Early Cretaceous and the proposal that birds competitively excluded pterosaurs from many key niches. However, although competition is often posited as a causal mechanism for many of the clade-clade replacements observed in the fossil record, these hypotheses are rarely tested. Here we present a detailed examination of pterosaur diversity through time, including both taxic and phylogenetically corrected diversity estimates and comparison of these estimates with a model describing temporal variation in the number of pterosaur-bearing formations (a proxy for rock availability). Both taxic and phylogenetic diversity curves are strongly correlated with numbers of pterosaur-bearing formations, suggesting that a significant part of the signal contained within pterosaur diversity patterns may be controlled by geological and taphonomic megabiases rather than macroevolutionary processes. There is no evidence for a long-term decline in pterosaur diversity through the Cretaceous, although a reduction in morphological, ecological, and phylogenetic diversity does appear to have occurred in the latest Cretaceous. Competitive replacement of pterosaurs by birds is difficult to support on the basis of diversity patterns.

scholarly journals Species Richness Capture Plant Functional and Phylogenetic Diversity Variations Along Different Ecosystems on the Hillsides of Damavand Mountain (Iran)

2021 ◽  
Author(s):  
majid sadeghinia ◽  
Bahram gholinejad ◽  
Mansoureh kargar
Keyword(s):  
Species Richness ◽  
Phylogenetic Diversity ◽  
Nutrient Concentration ◽  
Diversity Index ◽  
Seed Mass ◽  
Soil Nutrient ◽  
Functional Trait ◽  
Pairwise Distance ◽  
Phylogenetic Distance ◽  
Functional Richness

Abstract Aims Plants vary in their functional traits and thus in their preference towards edaphic conditions. Plants displaying tougher, long-living leaves, which better conserve nutrients in the tissues, are expected to grow better in acidic soils, which are frequently nutrient poor. Methods We used a trait-based approach, quantifying variations in the Leaf-height-seed (LHS) scheme and functional and phylogenetic indices in semi-arid communities from three different habitats (grasslands, shrubland and mixed habitats). Three traits, including specific leaf area (SLA), Plant height (H) and Seed Mass (SM), in 350 plots across the three habitats in the southern hillsides of Damavand Mountain. We only included the species that occurred in more than 20 plots throughout the dataset for the following analyses (i.e., 44 species). We calculated at the plot scale, community weighted means (CWM) for each trait, species richness, Faith’s phylogenetic diversity index (PD), functional richness (Frich), functional and phylogenetic mean pairwise dissimilarities (MPD) and nutrient concentration. Results The results showed that the higher soil nutrient concentration and pH were significant and positive related with species and functional richness and Faith´s phylogenetic distance, while not significant results were obtained for any functional trait at community level (SLACWM, VHCWM and SMCWM) or for the functional and phylogenetic mean pairwise distance.Conclusiones In addition, the phylogenetic and functional patterns responded more to the taxonomic richness variations than to trait-based assembly processes.

scholarly journals Understanding global patterns of mammalian functional and phylogenetic diversity

2011 ◽  
Vol 366 (1577) ◽  
pp. 2536-2544 ◽  
Author(s):  
Kamran Safi ◽  
Marcus V. Cianciaruso ◽  
Rafael D. Loyola ◽  
Daniel Brito ◽  
Katrina Armour-Marshall ◽  
...  
Keyword(s):  
Species Richness ◽  
Phylogenetic Diversity ◽  
Global Scale ◽  
Mean Annual Temperature ◽  
Residual Variance ◽  
Ecological Processes ◽  
Diversity Measures ◽  
Tropical Areas ◽  
Functional And Phylogenetic Diversity ◽  
Life On Earth

Documenting and exploring the patterns of diversity of life on Earth has always been a central theme in biology. Species richness despite being the most commonly used measure of diversity in macroecological studies suffers from not considering the evolutionary and ecological differences among species. Phylogenetic diversity (PD) and functional diversity (FD) have been proposed as alternative measures to overcome this limitation. Although species richness, PD and FD are closely related, their relationships have never been investigated on a global scale. Comparing PD and FD with species richness corroborated the general assumptions of surrogacy of the different diversity measures. However, the analysis of the residual variance suggested that the mismatches between the diversity measures are influenced by environmental conditions. PD increased relative to species richness with increasing mean annual temperature, whereas FD decreased with decreasing seasonality relative to PD. We also show that the tropical areas are characterized by a FD deficit, a phenomenon, that suggests that in tropical areas more species can be packed into the ecological space. We discuss potential mechanisms that could have resulted in the gradient of spatial mismatch observed in the different biodiversity measures and draw parallels to local scale studies. We conclude that the use of multiple diversity measures on a global scale can help to elucidate the relative importance of historical and ecological processes shaping the present gradients in mammalian diversity.

scholarly journals Phylogenetic diversity, functional trait diversity and extinction: avoiding tipping points and worst-case losses

2015 ◽  
Vol 370 (1662) ◽  
pp. 20140011 ◽  
Author(s):  
Daniel P. Faith
Keyword(s):  
Functional Traits ◽  
Phylogenetic Diversity ◽  
Functional Trait ◽  
Tipping Points ◽  
Worst Case ◽  
Diversity Measure ◽  
Trait Diversity ◽  
Option Values ◽  
Phylogenetic Model ◽  
Functional Trait Diversity

The phylogenetic diversity measure, (‘PD’), measures the relative feature diversity of different subsets of taxa from a phylogeny. At the level of feature diversity, PD supports the broad goal of biodiversity conservation to maintain living variation and option values. PD calculations at the level of lineages and features include those integrating probabilities of extinction, providing estimates of expected PD. This approach has known advantages over the evolutionarily distinct and globally endangered (EDGE) methods. Expected PD methods also have limitations. An alternative notion of expected diversity, expected functional trait diversity, relies on an alternative non-phylogenetic model and allows inferences of diversity at the level of functional traits. Expected PD also faces challenges in helping to address phylogenetic tipping points and worst-case PD losses. Expected PD may not choose conservation options that best avoid worst-case losses of long branches from the tree of life. We can expand the range of useful calculations based on expected PD, including methods for identifying phylogenetic key biodiversity areas.

Dominance determines fish community biomass in a temperate seagrass ecosystem

2019 ◽  
Author(s):  
Aaron Matthius Eger ◽  
Rebecca J. Best ◽  
Julia Kathleen Baum
Keyword(s):  
Species Richness ◽  
Ecosystem Function ◽  
Fish Community ◽  
Prey Capture ◽  
Fish Communities ◽  
Functional Trait ◽  
Ecosystem Functions ◽  
Community Biomass ◽  
Ecosystem Valuation ◽  
Species Abundances

Biodiversity and ecosystem function are often correlated, but there are multiple hypotheses about the mechanisms underlying this relationship. Ecosystem functions such as primary or secondary production may be maximized by species richness, evenness in species abundances, or the presence or dominance of species with certain traits. Here, we combined surveys of natural fish communities (conducted in July and August, 2016) with morphological trait data to examine relationships between diversity and ecosystem function (quantified as fish community biomass) across 14 subtidal eelgrass meadows in the Northeast Pacific (54° N 130° W). We employed both taxonomic and functional trait measures of diversity to investigate if ecosystem function is driven by species diversity (complementarity hypothesis) or by the presence or dominance of species with particular trait values (selection or dominance hypotheses). After controlling for environmental variation, we found that fish community biomass is maximized when taxonomic richness and functional evenness is low, and in communities dominated by species with particular trait values – those associated with benthic habitats and prey capture. While previous work on fish communities has found that species richness is positively correlated with ecosystem function, our results instead highlight the capacity for regionally prevalent and locally dominant species to drive ecosystem function in moderately diverse communities. We discuss these alternate links between community composition and ecosystem function and consider their divergent implications for ecosystem valuation and conservation prioritization.

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