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EN
The diversity of birds is directly correlated with the structure of the forest. Any interfering with the vegetation produces direct effects on the avifauna through the increase, decrease, or alternation of two key attributes: food and shelter. Thus, the composition of life in the forest is altered as changes occur in vegetation that directly interferes with the population structure of the avifauna, be those changes natural or anthropic. This study was realized in fragments of the Amazon Rainforest, and the main objective was to analyze the behavior of frugivorous and omnivorous birds in three different stages of ecological succession. In forest environments where a vertical stratification of resources occurs, these species are distributed occupying a in a high diversity of trophic niches. The diversity and density of the frugivorous and omnivorous birds in the forest fragments in medium and advanced stage of ecological succession could be directly correlated not only with the structure of the forest, but also to the fact that these birds feed almost exclusively on abundant and easy to find food sources - shrub and tree fruit of certain vegetable species that are naturally abundant in the rainforest understory layer.
EN
The objective of this study was accomplishes a knowledge survey of the Mura indigenous on the birds of natural occurrence in their territory, who is located in the Amazonas State, Brazilian Amazon Rainforest. As method for collect the data were used open and semi-structured interviews. Twenty four indigenous were interviewed, with both genres and different ages. The interviewees mentioned 118 different species of birds, counting about 60% of the records, which in addition to the interviews was completed by surveying the bird by direct field observations with sighting and vocalization in different natural environments of the indigenous territory. The indigenous showed wide ecological knowledge regarding these birds. The oral transmission of knowledge occurs across generations.
EN
Superstitions have their origins at the beginning of human civilization and makeup part of the very essence of human intellect. Indigenous peoples, due to their ethnic diversity, contributed in different ways with many cultural aspects. Religious beliefs and superstitions play an important role within Indigenous culture. The objective of this study was to accomplish a survey of the superstitions of some Indigenous peoples of the Amazon about certain species of birds. The method for collecting the data was used open and semi-structured interviews with Indigenous people from the Arara, Tenharim, Kayabi, and Apiaká ethnic groups.
EN
The objective of this study accomplished a knowledge survey of the Bororo indigenous on the birds of natural occurrence in their territory, Meruri village, who is located in the Mato Grosso State, Brazil, in the Savannah biome, and also the relationship of the indigenous with these birds. As the method for collect, the data were used open and semi-structured interviews. Twenty-two indigenous were interviewed, both genres and different ages. The interviewees mentioned 96 species of birds and they showed wide ecological knowledge regarding these birds. Such relationships are complex, being evidenced by a mythical interaction between the man and the elements of nature. These birds are important elements in the creation of stories, legends, in the Bororo ceremonies and arts. The oral transmission of knowledge occurs across generations.
EN
Darwinian theory of sexual selection and its development up to the present state of knowledge are sketched. The most important results of empirical studies on sexual selection in the Swallow Hirundo rustica are reviewed. The Swallow is a socially monogamous, slightly sexually dimorphic avian species. Long tail streamers are considered as sexual ornaments of males. Female preference for long and symmetric male tails has been inferred on both observational and experimental grounds. Experimental elongation of the tail causes short-term benefits and long-term costs in male reproductive performance. Behavioural consequences of sexual selection acting in the Swallow are discussed. An aerodynamic role of male tail streamers is also considered.
Kosmos
|
2018
|
vol. 67
|
issue 2
275-285
PL
W latach 90. XX w. nastąpił intensywny rozwój badań nad osobowością zwierząt, w których szczególnie często wykorzystanym modelem są ptaki. Opisano wiele wyznaczników osobowości u różnych gatunków, wśród których zwykle analizuje się sposób eksploracji środowiska, śpiew, poziom agresji, a także morfologiczne wyznaczniki osobowości takie jak ubarwienie. Wciąż jednak badacze borykają się z wieloma problemami, jak choćby efekt kontekstu. Podejmowane są także próby odnalezienia związków pomiędzy osobowością osobnika a doborem płciowym czy sukcesem rozrodczym. Celem niniejszego artykułu jest przedstawienie aktualnego stanu wiedzy na temat osobowości ptaków, a także kierunków przyszłych badań związanych z tym zjawiskiem.
EN
Since 1990s we have observed intense progress in studies on animal personality, especially on birds treated as a model. Up to date many indicators of personality have been described for different species, among which usually there were analysed: manner of environment exploration, singing, aggression level, and also some morphological indicators, e.g. plumage. Still, researchers are facing many problems such as effect of context. There are also attempts to find relationship between personality and sexual selection, or breeding success. Aim of this article is to show the state of art in birds' personality studies, and directions for future research.
Kosmos
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2017
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vol. 66
|
issue 4
595-608
PL
Wiele odkryć, fundamentalnych dla rozwoju biologii XX w., dokonało się dzięki badaniom prowadzonym na ptakach. Wśród nich należy wymienić opracowanie przez Ludwika Pasteura podstaw i praktycznego stosowania szczepionek oraz wskazanie przez Bruce'a Glicka roli bursy Fabrycjusza, istotnej dla zrozumienia podstawowych mechanizmów odpornościowych. Zwłaszcza poznanie funkcjonalnej dychotomii układu odpornościowego ptaków, u których bursa Fabrycjusza stanowi centralne miejsce dojrzewania limfocytów odpowiedzialnych za produkcję przeciwciał, skłoniło uczonych do poszukiwania u ssaków odpowiednika bursy Fabrycjusza. Dzięki tym odkryciom nowoczesna immunologia mogła zacząć swój dynamiczny rozwój, posługując się najnowszymi metodami biologii molekularnej. A bursa Fabrycjusza nadal przyciąga zainteresowanie wielu badaczy, wykrywających liczne peptydy pochodzenia bursalnego wywierające efekty regulacyjne nie tylko w układzie odpornościowym ptaków, lecz także o szerszym działaniu biologicznym, w odniesieniu do procesów odpornościowych ssaków, nowotworzenia czy działania antyoksydacyjnego. Cechy anatomiczne układu odpornościowego kury domowej, takie jak brak węzłów chłonnych, eozynofili czy limfocytów rezydujących mogą wskazywać na prostotę jego budowy. Dodatkowo zsekwencjonowanie genomu kury domowej pokazało, że u ptaków wiele procesów odpornościowych może się odbywać przy bardziej oszczędnym repertuarze cytokin, chemokin, receptorów i cząsteczek kostymulujących niż ten, który występuje u ssaków. Jednak to uproszczenie jest tylko pozorne, ponieważ układ odpornościowy ptaków spełnia właściwie wszystkie funkcje jakie spełnia układ odpornościowy ssaków.
EN
Attribution by Bruce Glick in the fifties/sixties of twenty century an essential role of the bursa of Fabricius in the differentiation of a particular lymphocyte population in the chicken was a milestone in the modern immunology development. Incoming studies on both avian and mammalian experimental models were able to prove a functional dissociation of the humoral and cell-mediated immune response and to demonstrate that the bursa of Fabricius plays an important role in antibody production. Subsequently, the research was oriented towards the identification of the mammalian "bursa-equivalent" where the antibody-producing lymphocytes, named B-cells in the honor to the bursa of Fabricius, should be generated. Finally, this role in mammals has been proven for the embryonic liver and for the bone marrow lymphopoiesis in the postnatal life. Apart from that, bursa of Fabricius is an endocrine organ producing several peptides exhibiting immunoregulatory activity, not only towards the avian immune functions but also influencing mammalian immunity, both in vivo and in vitro. The most important among them seem to be: bursin (tripeptide discovered as the first bursal peptide), BASP (bursal anti-steroidogenic peptide, exerting and inhibitory effect on the steroid hormone synthesis in the ovarian follicles and adrenal cortex) and bursopentin (BP5, a peptide with an antioxidative properties). The anatomical features of the domestic chicken immune system, such as lack of lymph nodes, eosinophils or resident lymphocytes, may indicate the simplicity of its organization. In addition, the sequencing of the domestic chicken genome has shown that many immune processes in birds may occur with a more scant repertoire of cytokines, chemokines, receptors and costimulatory molecules than those found in mammals. However, this simplification is only apparent because the avian immune system fulfills all the functions as those of the mammalian one.
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