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Many animals use acoustic signals for communication, implying that the properties of these signals can be under strong selection. The acoustic adaptation hypothesis predicts that species living in dense habitats emit lower-frequency sounds than those in open areas, because low-frequency sounds generally propagate further in denser vegetation. Signal frequency may also be under sexual selection, because it correlates with body size and lower-frequency sounds are perceived as more intimidating. Here, we evaluate these hypotheses by analysing variation in peak song frequency across 5,085 passerine species (Passeriformes). A phylogenetically-informed analysis revealed that song frequency decreases with increasing body mass and with male-biased sexual size dimorphism. However, we found no support for the predicted relationship between frequency and habitat. Our results suggest that the global variation in passerine song frequency is mostly driven by natural and sexual selection causing evolutionary shifts in body size rather than by habitat-related selection on sound propagation.Statement of authorshipTA and PM conceived and designed the study with input from all authors. TA and BK coordinated the study. PM collected the song data. MV performed the statistical analyses with input from WF. MB made the figures with help from MV and PM. TP and HB provided bioacoustic expertise. PM drafted the first version of the manuscript. TA, BK and PM revised and finalized the manuscript with input from all authors.Data availability statementThe data used in this study were collected from publicly available databases. All data and computer code used to generate the results, as well as supplementary figures and tables will be freely available at https://osf.io/fa9ky/.

Recently, there has been an increased effort to unravel selective factors behind female song evolution in songbirds. Female birds which produce songs may sing either solo or in duets; although the 2 vocal performances likely evolved through different selection forces and mechanisms, the majority of large-scale studies to date have focused only on duetting or female song in general (pooling female solo song and duetting into a single category). Hence, here we estimate the effect of behavioral life-history traits (territoriality, social bonds, and cooperative breeding) and environmental productivity on the occurrence of female solo song and duetting separately in songbirds of South Africa and Lesotho. The focal region is characterized by subtropical/tropical climate, clear spatial environmental productivity gradient, and detailed knowledge on avian species distribution and behavioral life-history traits. Phylogenetically informed comparative analyses revealed that species where females produce only solo songs exhibited higher levels of territoriality than species with nonsinging females (in an univariable model) but, simultaneously, lower levels than duetting species. Although both species with female solo song and duetting establish mainly long-term social bonds, the former defend their territories seasonally while the latter exhibit mainly year-round territoriality. Cooperative breeding and environmental productivity were not associated with the distribution of female solo song and duetting in any model. Our results indicate that when exploring female song ecology and evolution, female solo song and duetting are likely to be distinct song categories associated with different levels of territoriality.

Animals living close to human settlements more often experience disturbance, but also reduced predation risk. Because an escape response is costly, behavioural adjustments of animals in terms of increased tolerance of humans occurs and is often reported in the literature. However, most such studies have been conducted in and around long-existing cities in Europe and North America, on well-established animal populations. Here, we investigate the degree of tolerance of human disturbance across 132 bird species occurring in disturbed (small farms) and undisturbed (intact wetlands and grasslands) areas in Pantanal, Mato Grosso (Brazil), a region with only a very recent history of human-induced disturbance. We found a clear across-species trend toward higher tolerance of human disturbance in birds near farms when compared with birds in wild areas. Such a flexible and perhaps also rapid emergence of tolerance when facing small-scale and very recent human disturbance presumably involves learning and might be attributed to behavioural plasticity. The ability of birds to modify their degree of tolerance of human disturbance may play a key role in the facilitation of wildlife–human coexistence.

The definition of complete disease response (CR) in multiple myeloma (MM) continues to be reevaluated. The last widely accepted model of response assessment was proposed by the International Myeloma Working Group (IMWG) in 2016.1 Urine immunofixation (uIFE), one of the CR parameters, is being frequently omitted from CR evaluation in routine clinical practice. Patients with missing uIFE are then reported as having very good partial response (VGPR).2 It has been recently suggested in retrospective analysis by Lahuerta et al3 that patients with intact immunoglobulin myeloma (IIMM) who lack uIFE examination present with the very same prognosis as the patients with negative uIFE and therefore uIFE might not be necessary for CR definition in such patients.

Escape behaviour is a common antipredator strategy of lizards. Here, we studied the effect of several variables predicted to have a potential effect on escape behaviour of lizards. Specifically, we measured the effects of starting distance (SD), distance to cover, sex–age and the observer’s head orientation on flight initiation distance (FID) in the common agama Agama agama. Agamas were approached in urban localities in Limbe city, Cameroon, where they were habituated to the presence of humans. We found no association between FID and SD, but individuals closer to potential cover had shorter FID than individuals farther from a refuge. Juveniles escaped later than adults, but no significant differences were found in the FID between adult males and females. Head direction of the approaching observer had no effect on FID. This is, to the best of our knowledge, the first study investigating factors affecting FID in common agamas, extending our knowledge of risk-related behaviour in lizards of the Old World tropics.

Background The data on the clinical utility of the quantitative assessment of immunophenotypes in distinguishing mature CD5-positive B-cell neoplasms is limited. The study aim was to assess the diagnostic value of the quantitative assessment of a panel of 18 markers and to identify the most informative ones. Methods The immunophenotype of the neoplastic population was determined in diagnostic specimens from 188 patients. BD FACSCanto II flow cytometer and FACSDiva software were used to analyze the positivity/negativity and mean fluorescence intensity (MFI) of the surface expression of 18 markers. Advanced data mining methods were used to define the key differential diagnostic features of CLL/SLL (chronic lymphocytic leukemia/small lymphocytic lymphoma), MCL (mantle cell lymphoma), and CD5+ MZL (marginal zone lymphoma). Results The most informative markers for the distinction of CLL/SLL, MCL, CD5+ MZL, including atypical cases, were the MFI values of CD79b, CD20, CD23, CD43, CD38, CD11c, FMC7, CD200, kappa light chain, and their combinations. CD23 and CD200 were the most discriminant between CLL/SLL and MCL and CD23 plus CD79b between CLL/SLL and CD5+ MZL. The quantitative analysis of the most informative markers failed to accurately distinguish MCL and CD5+ MZL. The study highlights the data mining methods for the analysis and selection of the most informative immunophenotypic markers and for the design of a predictive model (diagnostic classifier), minimizing the subjectivity of expert-based assessment. Conclusions Our data confirmed that the quantification of the expression of informative markers increases the diagnostic value of immunophenotyping in mature CD5+ B-cell neoplasms. © 2017 International Clinical Cytometry Society.

In this paper, we present results of the study on the aberrant plumage colouration of the bird specimens deposited in the collection of the Sarisske Museum Bardejov (SMB), Slovakia. Out of ...

Animals, including birds, have to optimize their escape strategies under the risk of predation. Level of risk-taking is often estimated as flight initiation distance (FID), which is assumed to reflect the trade-off between costs of escape and benefits of staying put. Despite costs and benefits of escape may change during the season, previous studies have focused mainly on breeding bird populations. Here, we focused on risk taking in migratory and resident populations of waders (Charadriiformes) at the wintering grounds in tropical Africa. Phylogenetically informed comparative analyses revealed significant correlation between starting distance, body mass and, marginally, reproductive effort and FID, but no correlation between flock size and FID in wintering waders. Interestingly, despite no differences in body mass, reproductive effort and flock size, FID significantly differed between migratory and resident wader species after controlling for the potential effect of confounding variables, with FID being shorter in resident species. This suggests that such differences in risk perception are linked to some other factors as, for instance, the level of familiarity of waders with local environments at their wintering grounds and previous experience with humans. Our results may have also implications for avian conservation of migratory species at wintering grounds., PM and TA were financially supported through the Czech Science Foundation [14–36098G]. Field research in Kenya (MH) was supported by ITMS [26110230119] and VEGA [1/0977/16].

Recently, Pearse et al. explored the macroecology of passerine song using a large citizen science database of bird songs and machine learning techniques. They used standard deviation of frequency (SDF) as a surrogate for song complexity, finding only weak support for correlation between SDF and life-history traits such as monogamy and sexual dimorphism. Their finding that song complexity increases toward more productive environments and warmer areas seemingly contradicts several previous multitaxonomic studies. By comparing SDF scores with traditionally used song complexity metrics (syllable repertoire size and the number of syllable types per song), we found no evidence of any correlation. This may help to explain the discrepancy between their findings and findings of previous studies. While we agree that simple metrics that can be quantified and compared between multiple, highly variable species are crucial for progress in large-scale analysis of birdsong complexity, the biological relevance of SDF remains unclear and more research is needed to clarify its relevance for further studies of birdsong complexity.

1: Predation is an important selective pressure that can influence prey species in numerous ways. Predator–prey relationships are, however, poorly understood in taxa not typically associated with these interactions; this is especially the case when bats (Chiroptera) are the prey. 2: The main aim here is to review and synthesise global information on the predation of bats by birds of prey (Accipitriformes and Falconiformes) and other diurnal bird groups. #: We compiled data on incidences of predation of bats by diurnal birds, through an extensive multilingual study of bibliographic and Internet‐based sources. Scientific papers were found mainly via the Thomson Reuters (Web of Science and Zoological Record) and Scopus databases, Google Scholar, and Google Books. Additional data were found through Internet searches of trip reports, images and videos carried by Google, Google Images, Flickr, and YouTube. 4: In total, more than 1500 cases of bats being attacked by diurnal predatory birds were obtained. Reports were documented from every continent (except Antarctica) and from 109 countries, and were thus distributed globally between 70°N and 43°S. Overall, we found evidence for predation of bats by 143 species of diurnal raptors (Accipitriformes 107 spp. and Falconiformes 36 spp.) and by 94 non‐raptor bird species from 28 families. At least 124 and 50 bat species were taken as prey by raptors and by other diurnal bird species, respectively. 5: Attacks on bats by diurnal raptors were found to be distributed globally and were present in the majority of extant raptor lineages. Attacks on bats by other diurnal birds were also occasionally recorded. Furthermore, the majority of extant bat families featured as prey. These results strongly suggest that predation by birds may act as a major factor affecting the scarcity of daytime activity in bats and as a driver in the evolution of bat nocturnality.

Although bats (Chiroptera) belong to the most diverse mammalian orders, study of diversity of their natural predators has been seriously neglected for a long time. While some recent reviews contain comprehensive overviews of our recent knowledge on these phenomena for some animal groups, such work is still lacking for anamniotes - fishes and amphibians. Here, I am summarising bat predation incidences by anamniotes that were published in scientific journals and public web domains. I found out that at least 14 species of fishes and 14 species of frogs were observed as feeding on bats. Moreover, 7 and 16 species of bats were recorded as victims of hunting activity of fishes and frogs, respectively. Majority of localised incidences came from the New World; frog (between latitude 49°N to 28°S) attacks were distributed mainly in tropical or subtropical areas < 30° from equator (70% of all records), fish (44°N to 20°S) incidences reach same proportion in colder areas (> 30° from equator) and warmer areas. In some cases, these predators can regularly feed on bats, especially when hunting near roosting places of bats; however, with respect to number of recorded cases (21 for fishes and 37 for amphibians), bat predation by anamniotes seems to be very rare and opportunistic with only very limited influence on bat populations or their behaviour.

© The Author(s) 2018., Life-history theory predicts that current behaviour affects future reproduction, implying that animals should optimise their escape strategies to reflect fitness costs and benefits of premature escape. Both costs and benefits of escape may change temporally with important consequences for the evolution of escape strategies. Moreover, escape strategies of species may differ according to their positions on slow–fast pace of life gradients. We studied risk-taking in long-distance migratory animals, waders (Charadriiformes), during the annual cycle, i.e., breeding in Europe, stopover in the Middle East and wintering in tropical Africa. Phylogenetically informed comparative analyses revealed that risk-taking (measured as flight initiation distance, FID) changed significantly over the year, being lowest during breeding and peaking at stopover sites. Similarly, relationships between risk-taking and life-history traits changed among stages of the annual cycle. While risk-taking significantly decreased with increasing body mass during breeding, risk-taking–body mass relationship became marginally significant in winter and disappeared during migration. The positive trend of risk-taking along slow–fast pace of life gradient measured as adult survival was only found during breeding. The season-dependent relationships between risk-taking and life history traits suggest that migrating animals respond to fluctuating environments by adopting behavioural plasticity., Te study was fnancially supported by project OPV ITMS26110230119 and VEGA 1/0977/16. TA and PM were supported by Czech Science Foundation project (14–36098G). This paper is a contribution by MD to the thematic network REMEDINAL3-CM (S2013/ MAE-2719).

Birds sitting or feeding on live large African herbivorous mammals are a visible, yet quite neglected, type of commensalistic–mutualistic association. Here, we investigate general patterns in such relationships at large spatial and taxonomic scales. To obtain large-scale data, an extensive internet-based search for photos was carried out on Google Images. To characterize patterns of the structural organization of commensalistic–mutualistic associations between African birds and herbivorous mammals, we used a network analysis approach. We then employed phylogenetically-informed comparative analysis to explore whether features of bird visitation of mammals, i.e., their mean number, mass and species richness per mammal species, are shaped by a combination of host mammal (body mass and herd size) and environmental (habitat openness) characteristics. We found that the association web structure was only weakly nested for commensalistic as well as for mutualistic birds (oxpeckers Buphagus spp.) and African mammals. Moreover, except for oxpeckers, nestedness did not differ significantly from a null model indicating that birds do not prefer mammal species which are visited by a large number of bird species. In oxpeckers, however, a nested structure suggests a non-random assignment of birds to their mammal hosts. We also identified some new or rare associations between birds and mammals, but we failed to find several previously described associations. Furthermore, we found that mammal body mass positively influenced the number and mass of birds observed sitting on them in the full set of species (i.e., taking oxpeckers together with other bird species). We also found a positive correlation between mammal body mass and mass of non-oxpecker species as well as oxpeckers. Mammal herd size was associated with a higher mass of birds in the full set of species as well as in non-oxpecker species, and mammal species living in larger herds also attracted more bird species in the full set of species. Habitat openness influenced the mass of birds sitting on mammals as well as the number of species recorded sitting on mammals in the full set of species. In non-oxpecker species habitat openness was correlated with the bird number, mass and species richness. Our results provide evidence that patterns of bird–mammal associations can be linked to mammal and environmental characteristics and highlight the potential role of information technologies and new media in further studies of ecology and evolution. However, further study is needed to get a proper insight into the biological and methodological processes underlying the observed patterns.

Like other animals, primates respond to predation using behavioural adaptations. Hence, they should optimise their escape strategy under the risk of predation, and flee at a distance, referred to as flight initiation distance (FID), when the fitness-related benefits of staying are balanced against the costs of escape. However, there is an absence of FID studies in primates. In this study, we used vervet monkeys Chlorocebus pygerythrus, a medium-sized African cercopithecoid, as a model species to investigate the influence of environment type (urban and rural), group size (defined as the number of visible neighbours), sex and age on FID when approached by a human. We found significantly shorter FID among urban than rural monkeys; urban individuals delayed their escape compared to rural individuals. We found no relationship between FID and sex and age class, but FID was positively correlated with group size in both settings; urban monkeys live in smaller groups than monkeys in rural areas. As FID and group size are important predictors of predation risk perception in primates, results suggest that, despite probable effects of habituation, vervet monkeys in Uganda adjust their antipredator behaviour when coping with novel environments within human settlements. Our findings are consistent with some previous studies of risk perception in animals, and indicate that FID could be used as an alternative measure for predation risk in primates.

Fascination with animals and their behaviour is one the most prominent patterns persisting in all human cultures. During the last decades, however, technological development and public access to the Internet have increased the speed and the extent of information sharing at an unprecedented rate, in some cases even challenging the traditional methods used in science. In order to understand the extent of this influence, we focused on the behaviour of shrikes. Shrikes are an enigmatic group of songbirds with a unique behaviour of impaling prey. We employed an extensive Internet search on YouTube (YT), a very popular and increasingly important source of information worldwide, for videos recording shrikes. Our analyses revealed that the number of shrike videos on YT is strongly positively correlated with classical knowledge on shrikes from books and scientific articles. Our results also suggest that in some cases YT may provide an alternative source of information on shrike ecology and behaviour. YT videos may thus provide new insights into the study of certain species or subjects and help identify gaps in ecological studies, especially in poorly studied species. Electronic supplementary material The online version of this article (doi:10.1007/s00114-017-1470-8) contains supplementary material, which is available to authorized users.

Birds inhabiting urban areas have to cope with novel conditions. Unlike natural habitats, birds in urban environments are exposed to an increased human presence which often induces stress. Urban birds with reduced sensitivity to human disturbance can obtain benefits such as longer foraging time or decreased energy costs for escape. Here, I tested the hypothesis that the decrease in flight initiation distance (FID) to a potential predator (an approaching human) reflects adaptation to the level of disturbance expressed as pedestrian density. Moreover, I studied the Influence of habitat type and species on observed FIDs. I analysed 2117 flight distances (20 species of European birds) located in ten localities in Prague. I found that species and pedestrian density play a more important role in determining FIDs than the type of habitat. Moreover, urban populations exposed to increased pedestrian density had consistently shorter flight distances. This study provides empirical documentation of changes in anti-pr...

The process of establishing breeding populations of birds in small towns of Central Europe provides a unique opportunity to study them during synurbization in statu nascendi. Over the years 2006–2011, we investigated the breeding ecology of three coexisting thrush species Turdus spp. in the urban habitats of the town of Bardejov (NE Slovakia). We studied nest distribution, nest predation in relation to nest placement and the breeding success of the Common Blackbird T. merula, Fieldfare T. pilaris and Song Thrush T. philomelos. The study species differed significantly in terms of microhabitat characteristics and vertical spatial distribution, expressed as the nest location height (Blackbird < Song Thrush < Fieldfare), the distance from the town centre (Fieldfare < Song Thrush < Blackbird), the distance from the nest tree to human paths and buildings (Blackbird < Song Thrush < Fieldfare) and the average distance between breeding conspecific pairs (Fieldfare < Blackbird < Song Thrush). We also found...

A previously undescribed Trichophyton species was isolated from the nail of a 33-year-old man with a history of probable distal lateral subungual onychomycosis (without confirmation by mycological examination). The infection occurred for the first time five years earlier (in 2006) and affected the right great toenail, with complete clinical remission after treatment with ciclopirox olamine. This undescribed species was isolated during probable relapse in 2011, but its etiological significance was not confirmed, that is, direct microscopy was negative and additional clinical samples were not collected. The species is probably geophilic based on phylogenetic analysis (internal transcribed spacer [ITS] rDNA) and is most closely related to the anamorphic T. thuringiense, homothallic Arthroderma ciferrii (anamorph T. georgiae), and heterothallic A. melis. The new species is characterized by yellowish colonies, red reverse on several media, positive urease test, negative hair-perforation test, absence of growth at 34 ◦ C, absence of macroconidia, formation of one-celled clavate microconidia, and spiral hyphae. The species grows well on sterilized human hairs placed on agar medium without any additional nutrients and forms gymnothecium-like structures covered by peridial hyphae. The combination of unique micro- and macromorphological features and physiological and sequence data from four unlinked loci (ITS, benA, RPB2 ,a ndact1 gene) justified the proposal of a new species T. onychocola sp. nov.

Two new species of quill mites (Acari: Prostigmata: Syringophilidae) collected from passeriform and coraciiform birds from Kenya are described : Neoaulonastus apalis sp. nov. from Apalis porphyrolaema Reichenow and Neumann (Passeriformes: Cisticolidae) and Peristerophila upupi sp. nov. from Upupa epops Linnaeus (Coraciiformes: Upupidae). Additionally, 3 new host species: Cisticola hunteri Shelley, 1889; Acrocephalus baeticatus (Vieillot, 1817) and Ploceus xanthops (Hartlaub, 1862) from Kenya and two new localities are recorded for genera: Aulobia Kethley, 1970; Neoaulonastus Skoracki, 2004 and Syringophiloidus Kethley, 1970. The previous and the latest knowledge about syringophilid mites from Kenya is summarized in tabular form.