鸟类合作繁殖研究进展

合作繁殖是当前行为生态学研究的热点。目前,鸟类学工作者对鸟类合作繁殖开展了大量研究。本文在简单回顾鸟类合作繁殖研究历史发展基础之上,对鸟类合作繁殖的特征进行了归纳与总结,并依据最新研究对进化途径和进化假说进行了对比分析和探讨。最后,针对当前研究中存在的问题或不足,提出将来研究的目标和方向。     

The Neural Integration of Environmental Information by Seasonally Breeding Birds

SYNOPSIS. Songbirds show dramatic seasonal changes in theirpropensity to exhibit an endocrine response to environmentalstimuli that regulate the timing of reproduction. There is aclear cycle in their ability to respond to changes in photoperiodbut less is known about seasonal variation in their sensitivityto supplementary factors that augment the photo-induction ofgonadal growth and fine tune the final onset of breeding. Suchfactors include behavioral interactions with a mate and theavailability of a nest site. In birds, seasonal variations inthe neural processing of photoperiod are mediated by substantialmodifications in the availability of hypothalamic Gonadotropin-ReleasingHormone (GnRH). There is also evidence that the activity ofcertain monoamines, such as norepinephrine and serotonin, changesin discrete parts of the hypothalamus as a function of the bird'sphotoperiodic condition. However, it is not known whether theresponse to supplementary factors involves similar changes.In this paper, I review what is known about how the avian centralnervous system might integrate initial predictive information,such as photoperiod, and supplementary cues such as behavioralinteractions. Photoperiodic information is perceived by an encephalicphotoreceptor while supplementary stimuli are perceived by thevisual and auditory systems. Both types of information seemto converge on the GnRH system of neurons in the preoptic areaand the septum that regulate pituitary function. This suggeststhat future studies should concentrate on the connectivity ofthese GnRH positive cells to other parts of the central nervoussystem and on the regulation of GnRH activitiy in these cellsby endogenous and exogenous factors.     

Biogeography and Breeding in Gymnotiformes from Uruguay

This study was carried out in Uruguay (30–35°S), South America, with two complementary approaches. First, an extensive exploration of Uruguayan freshwaters allowed us to assess the distribution of the two major species of Gymnotiformes (out of 4) across sites. Gymnotus carapo was uniformly distributed in Uruguayan territory, whereas Brachyhypopomus pinnicaudatus was observed in the northern and eastern part of the country. There was a highly significant negative correlation between the relative abundance of Brachyhypopomus pinnicaudatus and pH and water conductivity. Moreover, these environmental factors are significant contributors to its spatial differences in relative abundance. Second, temperature, conductivity, photoperiod, and the structure of a Brachyhypopomus pinnicaudatus population were analyzed across seasons in a small lake over a two-year period. Water temperature and photoperiod exhibited important seasonal changes, whereas water conductivity remained low and relatively constant. The presence of sexually mature males, females, and the sudden increase of juveniles indicated the occurrence of the breeding season in November, December, and January, coinciding with high mean water temperatures and extreme photoperiod. These results agree with previous data that support the hypothesis of temperature as an important environmental factor for the onset of breeding in Gymnotiformes from the temperate zone.     

中国鸟类生物地理学研究回顾与展望

本文回顾总结了中国鸟类生物地理学的产生、发展、重要成果和未来的发展趋势.主要论述了以下五个方面:1.中国动物地理学简史及鸟类生物地理学的萌芽;2.鸟类动物地理区划的发展,并重点论述了岛屿鸟类区系调查与生物地理格局、中国台湾岛和海南岛与大陆鸟类区系的联系以及鸟类特有化现象;3.鸟类多样性的格局、形成与维持,并重点归纳了几...     

Environmental Gradients Explain Species Richness and Community Composition of Coastal Breeding Birds in the Baltic Sea

Scientifically-based systematic conservation planning for reserve design requires knowledge of species richness patterns and how these are related to environmental gradients. In this study, we explore a large inventory of coastal breeding birds, in total 48 species, sampled in 4646 1 km² squares which covered a large archipelago in the Baltic Sea on the east coast of Sweden. We analysed how species richness (α diversity) and community composition (β diversity) of two groups of coastal breeding birds (specialists, i.e. obligate coastal breeders; generalists, i.e. facultative coastal breeders) were affected by distance to open sea, land area, shoreline length and archipelago width. The total number of species per square increased with increasing shoreline length, but increasing land area counteracted this effect in specialists. The number of specialist bird species per square increased with decreasing distance to open sea, while the opposite was true for the generalists. Differences in community composition between squares were associated with differences in land area and distance to open sea, both when considering all species pooled and each group separately. Fourteen species were nationally red-listed, and showed similar relationships to the environmental gradients as did all species, specialists and generalists. We suggest that availability of suitable breeding habitats, and probably also proximity to feeding areas, explain much of the observed spatial distributions of coastal birds in this study. Our findings have important implications for systematic conservation planning of coastal breeding birds. In particular, we provide information on where coastal breeding birds occur and which environments they seem to prefer. Small land areas with long shorelines are highly valuable both in general and for red-listed species. Thus, such areas should be prioritized for protection against human disturbance and used by management in reserve selection.     

Global Biogeography and Quantitative Seasonal Dynamics of Gemmatimonadetes in Soil

Bacteria belonging to phylum Gemmatimonadetes comprise approximately 2% of soil bacterial communities. However, little is known of their ecology due to a lack of cultured representation. Here we present evidence from biogeographical analyses and seasonal quantification of Gemmatimonadetes in soils, which suggests an adaptation to low soil moisture.     

Breeding and Migrating Birds in an Amazonian Savanna

Seasonal occurrence, breeding and migration records are presented for about 150 species of birds, monitored during a four years survey in an Amazonian savanna near Alter do Chão, Pará state, Brazil, by means of mist netting and observations along transects and on random walks. About half of the recorded species were Passeriformes. The local avifauna was mostly comprised of residents, with major breeding activities during the dry season, August through February. Thirteen non-resident species were classified as migrants which is considered a rather small fraction. Calculations of the total number of species expected to occur at the study site are presented. The composition of this savanna bird community is discussed under aspects of seasonality and migrational activity. The data are compared with records from other cerrado habitats in Amazonia and elsewhere, especially in Central Brazil. Resumo Registros de ocorrência sazonal, reprodução e migração são apresentados para cerca de 150 espécies de aves, monitoradas durante quatro anos de levantamentos em uma savana Amazônica perto de Alter do Chão, Estado do Pará, Brasil, através de redes ornitológicas, observaç[otilde]es ao longo de transectos e caminhadas ao acaso. Perto da metade das espécies registradas foram passeriformes. A avifauna local foi constituída principalmente de espécies residentes, com o pico de atividades reprodutivas durante a estação seca, ou seja 80% das espécies reproduzindo de Agosto até Fevereiro. Este padrão se repetiu em 1988 e 1989. Juvenis foram capturados durante todo o ano com picos durante a estação chuvosa. Treze espécies não residentes foram consideradas migrantes os quais são uma pequena fração da comunidade. Estimativas do número total esperado de espécies ocorrendo na área de estudo são apresentados. As capturas com redes ornitológicas em 4 ha resultaram em 41 espécies e para 13 ha, 64 espécies. Quando a área amostrada foi duplicada para 24 ha, o número de espécies aumentou em somente 4 e correspondeu à metade do total registrado para a área. O número assintótico estimado para 13 ha foi de 82 espécies o qual foi similar ao número estimado para 24 ha (80 espécies). A composição desta comunidade de aves de savana é discutida sob os aspectos de sasonalidade e atividades migratórias. Os resultados são comparados com registros de outros habitats de cerrado na Amazônia e outros locais especialmente no Brasil central.     

鸟类繁殖参数的相关分析

收集了国内学者近几十年来对鸟类繁殖生态的研究资料,分析了卵重、卵的长径、卵的短径、孵化期的相互关系。列出８个回归方程,对比以卵重孵化期及以卵的长径和卵的短径求孵化期的准确性。