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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]

• 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]