Search

Insect populations have become increasingly threatened during the last decades due to climate change and landuse intensification. Species characteristics driving these threats remain poorly understood. Trait‐based analyses provide a straight‐forward approach to gain a mechanistic understanding of species' extinction risk, guiding the development of conservation strategies. We combined morphological traits and phylogenetic relationship for 332 European species of butterflies and 115 species of odonates (dragon and damselflies) to model their red list status via phylogenetically controlled ordered logistic regression. We hypothesized that extinction risk increases with increasing body volume and wing area, decreasing range size, and is larger for brighter species. All investigated traits exhibited a strong phylogenetic signal. When controlling for phylogenetic relationship, we found that extinction risk of butterflies increased with decreasing range size. The extinction risk of odonates showed no relationship with the selected traits. Our results show that there is no universal trait defining the extinction risk of our investigated insect taxa. Furthermore, evolutionary history, measured as the phylogenetically predicted part of our analyzed traits, poorly predicted extinction risk. Our study confirms the focus of conservation measures on European butterfly species with small range sizes. [ABSTRACT FROM AUTHOR]

Abstract Insect populations have become increasingly threatened during the last decades due to climate change and landuse intensification. Species characteristics driving these threats remain poorly understood. Trait‐based analyses provide a straight‐forward approach to gain a mechanistic understanding of species' extinction risk, guiding the development of conservation strategies. We combined morphological traits and phylogenetic relationship for 332 European species of butterflies and 115 species of odonates (dragon and damselflies) to model their red list status via phylogenetically controlled ordered logistic regression. We hypothesized that extinction risk increases with increasing body volume and wing area, decreasing range size, and is larger for brighter species. All investigated traits exhibited a strong phylogenetic signal. When controlling for phylogenetic relationship, we found that extinction risk of butterflies increased with decreasing range size. The extinction risk of odonates showed no relationship with the selected traits. Our results show that there is no universal trait defining the extinction risk of our investigated insect taxa. Furthermore, evolutionary history, measured as the phylogenetically predicted part of our analyzed traits, poorly predicted extinction risk. Our study confirms the focus of conservation measures on European butterfly species with small range sizes.

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Diatoms are a keystone algal group, with diverse cell morphology and a global distribution. The biogeography of morphological, functional, and life-history traits of marine diatoms were investigated in Arctic and Atlantic waters of the Labrador Sea during the spring bloom (2013-2014). In this study, trait-based analysis using community-weighted means showed that low temperatures (< 0°C) in Arctic waters correlated positively with diatom species that have traits such as low temperature optimum growth and the ability to produced ice-binding proteins, highlighting their sea ice origin. High silicate concentrations in Arctic waters, as well as sea ice cover and shallow bathymetry, favoured diatom species that were heavily silicified, colonial and capable of producing resting spores, suggesting that these are important traits for this community. In Atlantic waters, diatom species with large surface area to volume ratios were dominant in deep mixed layers, whilst low silicate to nitrate ratios correlated positively with weakly silicified species. Sharp cell projections, such as processes or spines, were positively correlated with water-column stratification, indicating that these traits promote positive buoyancy for diatom cells. Our trait-based analysis directly links cell morphology and physiology with diatom species distribution, allowing new insights on how this method can potentially be applied to explain ecophysiology and shifting biogeographical distributions in a warming climate.

• Chinese birds with larger clutch sizes and more generalist diets were the most tolerant of urban environments. • Omnivores nesting on architectural buildings or cliffs showed higher urban tolerance within clades. • We provide novel evidence in Chinese birds and highlight challenges in identifying consistent trait-urban tolerance patterns. • We recommend compensating habitat and food resources for ground-nesters and summer migrants. The acceleration of urbanization has globally threatened bird diversity. Understanding how birds respond to the urban environment, and what, if any, traits predict this response to urban environments, is crucial in mitigating these declines. However, existing research often focuses on local or regional scales, utilizes restricted measures of urban tolerance, and does not always consider the interaction between evolutionary relatedness and traits, resulting in an unsettled relationship between some traits and urban tolerance. Our analyses aimed to test whether there is generalizability in previous results with that of the results in China, integrating 947,030 citizen science observations of birds with a continuous measure of urbanization. We synthesized an urbanization index for 874 species, representing their tolerance to urbanization by accounting for stressors such as built-up land, population density, and night-light intensity. First, we aimed to quantify which traits were positively and negatively associated with urban tolerance in Chinese birds, when considering all possible ecological and life history traits. Second, we tested specific hypotheses, based on a priori literature. Third, we tested whether the results from above change when phylogenetic relatedness is included in the models. The findings reveal that passage migrants or species with multiple main migration types with larger clutch sizes and more generalist diets are the most common in urban environments. Moreover, the evolutionary relationship between species conceals the expression of several traits in urban tolerance that omnivorous species that nest on architectural buildings or cliffs showed higher urban tolerance within clades. Our findings highlight the challenges in identifying consistent patterns in the relationships between species traits and their tolerance of urban environments. To optimize urban design and reduce the negative influence on birds from rapid urbanization, protecting existing trees and buildings where birds nest, increasing the proportion of shrubs to compensate for sources of ground-dwelling birds, and controlling the predation risk of the ground nests are beneficial. [ABSTRACT FROM AUTHOR]

The study of near-pristine estuaries can be used as a tool for mitigation projects of harmful effects in anthropogenic eutrophic systems, since one can analyze the effect of temporal and spatial variations generated mainly by natural forces. Phytoplankton taxonomy has been used as a classical indicator to assess changes in transitional water communities, however alternative methods based on morphological, behavioral and physiological traits offer the opportunity to compare sites or moments with different taxonomic compositions. Our goal, in this context, is to evaluate phytoplankton community short-term and seasonal variability in a near-pristine estuary, Barra Grande estuary (Ilha Grande, RJ, Brazil), through species functional traits and thus community functional diversity. Samplings were carried out in a mooring in complete tidal cycles, seasonally during 2012. Our results showed a diverse phytoplankton community with 38 frequent and abundant taxa, marked by density variation (1.2 × 10.4-2 × 10.7 cell L−1) in depth, with abundance inversely related to tidal currents. The functional structure of the phytoplankton community measured by functional diversity ( FD), varied seasonally in and across a gradient of tidal energy. A core community, mainly represented by flagellates and dinoflagellates, occurred in all observations and was highly functional (high FD), exploiting a variety of habitats. The chain-forming diatoms were associated with high tidal energy, and occurred in higher densities during summer. Phytoplankton cell size, cell shape, and the ability to form colonies are extremely plastic traits that can be regulated by the environment, however, isolated tychopelagic diatoms were present in the study area across all seasons, with higher contributions in autumn and winter, reflecting the shallow characteristic of this system. During the winter, an exposed sandbar was formed, and the lack of connection with the ocean resulted in an abundance of riverine and brackish water taxa. In this near-pristine estuary the densities and occurrences of HAB phytoplankton are low. Trait-based analyses add information about community structure, which can be impacted by anthropogenic actions in urbanized coastal systems. Thus the information provided by this study regarding phytoplankton functional diversity and its relation to nutrients and hydrography in Barra Grande Estuary can be applied as a baseline model for the development of public policies. [ABSTRACT FROM AUTHOR]

Monaghan and Soares (2014) suggested that combining traits with log-transformed abundance of taxa may cause anomalies in analyses of stream macroinvertebrate communities. While they addressed an important issue in stream ecology, here we present an opposite view. To identify the causes of these contrasting opinions, we carefully examined the examples provided by Monaghan and Soares (2014) and demonstrated how traits can be weighted by the presence, abundance and log-transformed abundance of the taxa in a meaningful way., We found that Monaghan and Soares (2014), following other authors, use the term 'weighting' differently from classical papers of stream ecology. The general practice is to calculate the sum of trait values multiplied by the abundance of each taxon and divide it by the total invertebrate abundance to get a community-level trait value. In contrast, Monaghan and Soares (2014) did not perform the final division and consequently did not get a standardised community-level trait value. It follows that the term 'weighting' is used with different meanings in stream ecology, and ecologists should keep these differences in mind., We agree with Monaghan and Soares (2014) that the addition of log-transformed data is equivalent to multiplication on an arithmetic scale. However, we disagree that this provides an inconsistent scaling that confounds quantitative analyses. Using example data sets, we illustrate how trait-based data analysis can be performed in community ecology in a meaningful way. [ABSTRACT FROM AUTHOR]