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Biological responses to climate change have been widely documented across taxa and regions, but it remains unclear whether species are maintaining a good match between phenotype and environment, i.e. whether observed trait changes are adaptive. Here we reviewed 10,090 abstracts and extracted data from 71 studies reported in 58 relevant publications, to assess quantitatively whether phenotypic trait changes associated with climate change are adaptive in animals. A meta-analysis focussing on birds, the taxon best represented in our dataset, suggests that global warming has not systematically affected morphological traits, but has advanced phenological traits. We demonstrate that these advances are adaptive for some species, but imperfect as evidenced by the observed consistent selection for earlier timing. Application of a theoretical model indicates that the evolutionary load imposed by incomplete adaptive responses to ongoing climate change may already be threatening the persistence of species.

Understanding the mechanism by which non‐native fish species integrate into native communities is crucial for evaluating the possibility of their establishment success. The genus Pangasianodon, comprising Pangasianodon gigas and Pangasianodon hypophthalmus, has been introduced into reservoirs, which are non‐native habitats, for fishery stock enhancement. P. gigas and P. hypophthalmus often successfully establish and co‐occur in several Thai reservoirs, but there is little information on differences in food resource use between the two species. To investigate the trophic niche width of P. gigas and P. hypophthalmus in a Thai reservoir, we conducted stable carbon and nitrogen ratio (δ13C and δ15N) analyses. We examined the degree of individual specialization in both species using the δ13C and δ15N values of muscle and liver tissues, which provides long‐ and short‐term diet information. The isotopic niches did not overlap between P. gigas and P. hypophthalmus. The δ15N value of P. gigas was significantly higher than that of P. hypophthalmus, whereas the δ13C value did not significantly differ between the two species. The isotopic niche sizes were larger in P. hypophthalmus than in P. gigas. Individual specialization was observed in P. hypophthalmus but not in P. gigas, indicating that intraspecific variation in food resource use was larger in P. hypophthalmus compared to P. gigas. These findings suggest that trophic niche partitioning was one of the factors facilitating the establishment success of P. gigas and P. hypophthalmus in a reservoir, but the establishment process may differ between the two species. [ABSTRACT FROM AUTHOR]

Analysing migration patterns can be used to predict the likelihood of invasion by exotic species, and disease prevalence and spread through contact networks in animals. This paper presents an analytical method for surveying the characteristics of wildlife migration, which can be challenging due to the varying distances and directions that animals travel and the diverse characteristics of different species. To gain a comprehensive understanding of migratory behaviour, it is necessary to integrate migration interrelationships within the populations and correlated migratory modes, e.g., aggregation or dispersed patterns. To achieve this, we propose the SSS-PCA method, which combines the small-shuffle surrogate (SSS) method and principal component analysis (PCA). The SSS-PCA method involves three major steps: (1) applying the SSS method to break down the time-series correlational structure of the movement data with different time frames, (2) obtaining some mobility indicators, e.g., the range and variance of movement, from the original and SSS data with different time frames, and (3) performing PCA on the mobility indicators, and clustering the results. The proposed method can reveal the migration patterns of individuals and the influence of individuals on the whole group. The SSS-PCA method can be used to examine the migration patterns of marine and terrestrial animal species. We suggest that the method can be applied to further studies of various species' migration data. [ABSTRACT FROM AUTHOR]

River ecosystems host a continuum of various discontinuities, such as dams and tributary inflows, which shape the habitats of aquatic organisms; this makes it important to evaluate the interactions among discontinuities and effects of a single discontinuity point. Herein, we focused on tributaries in dammed rivers to elucidate a manner to mediate discontinuities and hypothesized that the effects of the tributary inflow on the downstream river were mediated by the (1) distance between the dam and tributary inflow, (2) size ratio between the dam and tributary, and (3) ability of the tributary to transport fine sediments, such as sand and gravel. We conducted field investigations to measure 24 environmental factors, including the water column, riverbed, and river topography, along eight dammed rivers to test the three hypotheses. Only five factors differed significantly between the upstream and downstream sites of the tributary confluence, whereas 12 factors differed significantly between the tributary and mainstem. We also classified the variation pattern using principal component analysis (PCA). The correlation between each PCA axis and environmental factors suggests that the modifications of the water quality factors by tributary inflow were significantly correlated with the distance between the dam and the tributary inflow, and that the flux of various riverbed factors, that is, was significantly correlated with the ability to resupply of fine riverbed sediments by the tributary. Overall, tributary‐inflow downstream of a dam has the potential to be applicable in environmental restoration, especially in terms of resupplying fine sediment. [ABSTRACT FROM AUTHOR]