| [the genotyping of the west nile virus in birds in the far eastern region of russia in 2002-2004]. | samples from 20 species of trapped and dead birds were collected in the far eastern region in 2002-2004 and were analyzed by the anti-wnv mab-modified immunoenzyme assay for antigen detection and rt-pcr for viral rna detection. five positive samples from cinereous vultures (aegypius monachus) and two positive samples from cattle egret (bubulcus ibis) were found in both tests. the sequencing of the 322 bp fragments of protein e gene showed 99-99.67% homology with the strain wnv/leiv-vlgoo-27924 o ... | 2006 | 17094656 |
| caterpillar abundance in the territory affects the breeding performance of great tit parus major minor. | the effects of caterpillar food supply on the breeding performance of a population of the japanese great tit parus major minor were investigated. since more than 90% of the food items in our study site were caterpillars living on trees, we estimated the food availability using 20 frass traps per hectare. the sampling error of this method was about 10% on average, which was accurate enough to detect differences between territories. food abundance at laying in each territory affected the timing of ... | 1998 | 28307900 |
| nest predation risk influences a cavity-nesting passerine during the post-hatching care period. | some nest predators visually assess parental activities to locate a prey nest, whereas parents modify fitness-related traits to reduce the probability of nest predation, and/or nestlings fledge early to escape the risky nest environment. here, we experimentally tested if the parental and fledging behaviours of oriental tits (parus minor) that bred in the nest-box varied with cavity conditions associated with nest predation risk during the nestling period. the entrance of experimental nest-boxes ... | 2016 | 27553176 |
| warning signals confer advantage to prey in competition with predators: bumblebees steal nests from insectivorous birds. | aposematic (warning) signals of prey help predators to recognize the defended distasteful or poisonous prey that should be avoided. the evolution of aposematism in the context of predation has been in the center of modern ecology for a long time. but, the possible roles of aposematic signals in other ecological contexts have been largely ignored. here we address the role of aposematic signals in competition between prey and predators. bumblebees use visual and auditory aposematic signals to warn ... | 2013 | 23853395 |
| wild birds use an ordering rule to decode novel call sequences. | the generative power of human language depends on grammatical rules, such as word ordering, that allow us to produce and comprehend even novel combinations of words [1-3]. several species of birds and mammals produce sequences of calls [4-6], and, like words in human sentences, their order may influence receiver responses [7]. however, it is unknown whether animals use call ordering to extract meaning from truly novel sequences. here, we use a novel experimental approach to test this in a wild b ... | 2017 | 28756952 |
| assessment of predation risk through referential communication in incubating birds. | parents of many bird species produce alarm calls when they approach and deter a nest predator in order to defend their offspring. alarm calls have been shown to warn nestlings about predatory threats, but parents also face a similar risk of predation when incubating eggs in their nests. here, i show that incubating female japanese great tits, parus minor, assess predation risk by conspecific alarm calls given outside the nest cavity. tits produce acoustically discrete alarm calls for different n ... | 2015 | 25985093 |
| experimental evidence for compositional syntax in bird calls. | human language can express limitless meanings from a finite set of words based on combinatorial rules (i.e., compositional syntax). although animal vocalizations may be comprised of different basic elements (notes), it remains unknown whether compositional syntax has also evolved in animals. here we report the first experimental evidence for compositional syntax in a wild animal species, the japanese great tit (parus minor). tits have over ten different notes in their vocal repertoire and use th ... | 2016 | 26954097 |
| other species' alarm calls evoke a predator-specific search image in birds. | many animals produce vocal alarm signals when they detect a predator, and heterospecific species sharing predators often eavesdrop on and respond to these calls [1]. despite the widespread occurrence of interspecific eavesdropping in animals, its underlying cognitive process remains to be elucidated. if alarm calls, like human referential words, denote a specific predator type (e.g., "snake!"), then receivers may retrieve a mental image of the predator when hearing these calls [2-4]. here, using ... | 2020 | 32413306 |
| referential calls coordinate multi-species mobbing in a forest bird community. | japanese great tits (parus minor) use a sophisticated system of anti-predator communication when defending their offspring: they produce different mobbing calls for different nest predators (snake versus non-snake predators) and thereby convey this information to conspecifics (i.e. functionally referential call system). the present playback experiments revealed that these calls also serve to coordinate multi-species mobbing at nests; snake-specific mobbing calls attracted heterospecific individu ... | 2016 | 27829698 |
| imagery in wild birds: retrieval of visual information from referential alarm calls. | japanese tits (parus minor) produce specific alarm calls when they encounter a predatory snake. a recent field experiment showed that receiver tits became visually perceptive to an object resembling a snake when hearing these calls. however, the tits did not respond to the same object when hearing other call types or when the object was dissimilar to a snake. these findings provide the first experimental evidence for the retrieval of a visual search image from specific alarm calls, offering a no ... | 2019 | 30847677 |
| call combinations in birds and the evolution of compositional syntax. | syntax is the set of rules for combining words into phrases, providing the basis for the generative power of linguistic expressions. in human language, the principle of compositionality governs how words are combined into a larger unit, the meaning of which depends on both the meanings of the words and the way in which they are combined. this linguistic capability, i.e., compositional syntax, has long been considered a trait unique to human language. here, we review recent studies on call combin ... | 2018 | 30110321 |
| alarm calls evoke a visual search image of a predator in birds. | one of the core features of human speech is that words cause listeners to retrieve corresponding visual mental images. however, whether vocalizations similarly evoke mental images in animal communication systems is surprisingly unknown. japanese tits (parus minor) produce specific alarm calls when and only when encountering a predatory snake. here, i show that simply hearing these calls causes tits to become more visually perceptive to objects resembling snakes. during playback of snake-specific ... | 2018 | 29378940 |