Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species-level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, including six ecological variables, 11 continuous morphological traits, and information on range size and location. Raw morphological measurements are presented from 90,020 individuals of 11,009 extant bird species sampled from 181 countries. These data are also summarised as species averages in three taxonomic formats, allowing integration with a global phylogeny, geographical range maps, IUCN Red List data and the eBird citizen science database. The AVONET dataset provides the most detailed picture of continuous trait variation for any major radiation of organisms, offering a global template for testing hypotheses and exploring the evolutionary origins, structure and functioning of biodiversity.

"Across-year social stability shapes network structure in wintering migrant sparrows" (2014 IntroductionThe social structure of animal populations-e.g. the size, composition and stability of social groups-is a fundamental aspect of social evolution (Alexander 1974). In birds, studies of breeding systems have shown that ecological conditions can favor different social structures ranging from simple pairs to cooperative breeding groups (Emlen 1982). The winter social structure of year-round resident birds has also been investigated, but to a lesser degree than for the breeding season (Ekman 1989;Kraaijeveld & Dickinson 2001;Aplin et al. 2012). In migratory birds, the most basic aspect of winter social structure is known for many species-e.g. territoriality versus flocking in social groups. However, in species that form flocks (defined here as temporary aggregations of individuals in the same place at the same time), we know almost nothing about dynamics of flock membership over space and time (see Myers 1983;Piper & Wiley 1990;Conklin & Colwell 2008 for notable exceptions).Our lack of understanding of the winter societies of smallbodied birds is particularly surprising because these taxa were so crucial to the development of important theories in ecology. A large body of influential research on small-bodied birds in winter explored how food, predation and sociality interact to affect the evolution of optimal foraging (Stephens & Krebs 1986), sociality and optimal group size (Pulliam & Caraco 1984), energy management (Cuthill & Houston 1997), predator-prey interactions (Bertram 1978) and status signals (Rohwer 1975;Rohwer & Ewald 1981). For many of these topics, the pattern of group stability and the specific identities of group members matter. For example, the degree to which individuals form long-term associations could alter the dynamics of anti-predator behaviors and the form of cooperation involved Micheletta et al. 2012). In addition, the pattern of social structure also has critical implications for the mechanisms by which intragroup competition is mediated by signals (Rohwer 1975).In theory, the social structure of wintering birds could range from the small, highly stable groups observed in a variety of year-round resident birds (e.g. Ekman 1989) to short-term random associations with little or no structure (Myers 1983;Conklin & Colwell 2008). Between these two extremes, winter bird societies could also involve a complex mix of social stability and change in both space and timeoften termed fission-fusion dynamics (Aureli et al. 2008). Migration poses an added challenge to across-year stability because individuals that winter together do not necessarily breed together (Ryder et al. 2011;Seavy et al. 2012), and thus long-term social bonds must bridge a break in contact between winter seasons. However, high levels of site fidel- Published in Ecology Letters AbstractMigratory birds often form flocks on their wintering grounds, but important details of social structure such as the patterns of association betwe...

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How the microbiome interacts with hosts across evolutionary time is poorly understood. Data sets including many host species are required to conduct comparative analyses. Here, we analyzed 142 intestinal microbiome samples from 92 birds belonging to 74 species from Equatorial Guinea, using the 16S rRNA gene. Using four definitions for microbial taxonomic units (97%OTU, 99%OTU, 99%OTU with singletons removed, ASV), we conducted alpha and beta diversity analyses. We found that raw abundances and diversity varied between the data sets but relative patterns were largely consistent across data sets. Host taxonomy, diet and locality were significantly associated with microbiomes, at generally similar levels using three distance metrics. Phylogenetic comparative methods assessed the evolutionary relationship between the microbiome as a trait of a host species and the underlying bird phylogeny. Using multiple ways of defining “microbiome traits”, we found that a neutral Brownian motion model did not explain variation in microbiomes. Instead, we found a White Noise model (indicating little phylogenetic signal), was most likely. There was some support for the Ornstein‐Uhlenbeck model (that invokes selection), but the level of support was similar to that of a White Noise simulation, further supporting the White Noise model as the best explanation for the evolution of the microbiome as a trait of avian hosts. Our study demonstrated that both environment and evolution play a role in the gut microbiome and the relationship does not follow a neutral model; these biological results are qualitatively robust to analytical choices.

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.

The behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment1–4. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions1,5, but free-living individuals have to temporally synchronize their activities with those of others, including potential mates, competitors, prey and predators6–10. Individuals can temporally segregate their daily activities (e.g. prey avoiding predators, subordinates avoiding dominants) or synchronize their activities (e.g. group foraging, communal defence, pairs reproducing or caring for offspring)6–9,11. The behavioural rhythms that emerge from such social synchronization and the underlying evolutionary and ecological drivers that shape them remain poorly understood5–7,9. Here, we address this in the context of biparental care, a particularly sensitive phase of social synchronization12 where pair members potentially compromise their individual rhythms. Using data from 729 nests of 91 populations of 32 biparentally-incubating shorebird species, where parents synchronize to achieve continuous coverage of developing eggs, we report remarkable within– and between-species diversity in incubation rhythms. Between species, the median length of one parent’s incubation bout varied from 1 – 19 hours, while period length–the time in which a parent’s probability to incubate cycles once between its highest and lowest value – varied from 6 – 43 hours. The length of incubation bouts was unrelated to variables reflecting energetic demands, but species relying on crypsis (the ability to avoid detection by other animals) had longer incubation bouts than those that are readily visible or actively protect their nest against predators. Rhythms entrainable to the 24-h light-dark cycle were less prevalent at high latitudes and absent in 18 species. Our results indicate that even under similar environmental conditions and despite 24-h environmental cues, social synchronization can generate far more diverse behavioural rhythms than expected from studies of individuals in captivity5–7,9. The risk of predation, not the risk of starvation, may be a key factor underlying the diversity in these rhythms.

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