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1.
刘勇  戴轩  张珍梁 《蛛形学报》2010,19(2):107-109
报道了贵州东部地区茶园土壤甲螨104种,分属42科.以奥甲螨科、单翼甲螨科、盲甲螨科、菌甲螨科、上罗甲螨科等为茶园土壤甲螨优势类群,其中新小奥甲螨OppieUa nova,卵角单翼甲螨Rostrozetes ovulum,棒菌甲螨Scheloribates latipes,长刺表珠甲螨Epidameus longispinosus,异毛裂甲螨 Meristacarus heterotrichus,棘洼甲螨Camisia spinifer,缓三盲甲螨Trimalconothrus tardus,双毛角甲螨Ceratoppia bipillis,南方珠足甲螨Belba sasakawail,叶小盾珠甲螨Sactobelbella frondosa,尼兰奥甲螨Oppia neerlandia等为茶园土壤甲螨类动物常见种类.  相似文献   

2.
Avian neoptile feathers are defined as the first feather generation, which covers the chick after hatching, and usually described as simple structures consisting of numerous downy barbs which are radially symmetrically arranged and come together in a short calamus. In contrast, in some birds (e.g., Anas platyrhynchos, Dromaius novaehollandiae) the neoptile feathers have a prominent rhachis, and therefore display clear bilateral symmetry. Because the symmetrical variety found in neoptile feathers is poorly understood, their morphology was studied in a more comprehensive and phylogenetic approach. Neoptile body feathers from over 22 bird species were investigated using light microscopy, SEM, and MicroCT. Characters such as an anterior–posterior axis, a central rhachis, medullary cells, and structure of the calamus wall were defined and mapped onto recent phylogenetic hypotheses for extant birds. It can be shown that bilaterally symmetric neoptile feathers (with a solid calamus wall) were already present in the stem lineage of crown‐group birds (Neornithes). In contrast, simple radially symmetric neoptile feathers (with a fragile calamus wall) are an apomorphic character complex for the clade Neoaves. The simple morphology of this feather type may be the result of a reduced period of development during embryogenesis. To date, embryogenesis of neoptile feathers from only a few bird species was used as a model to reconstruct feather evolution. Because this study shows that the morphology of neoptile feathers is more diverse and even shows a clear phylogenetic signal, it is necessary to expand the spectrum of “model organisms” to species with bilaterally symmetric neoptile feathers and compare differences in the frequency of feather development from a phylogenetic point of view. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.  相似文献   

3.
Domesticated birds exhibit a greater diversity in the morphology of their integument and its appendages than their wild ancestors. Many of these variations affect the appearance of a bird significantly and have been bred selectively by poultry and pigeon fanciers and aviculturists for the sake of visual appeal. Variations in feather distribution (e.g., feathering of legs and feet, featherless areas in normally feather-bearing skin) are widespread in chickens and pigeons. Variations in the number of feathers (e.g., increased number of tail feathers, lack of tail feathers) occur in certain pigeon and poultry breeds. Variations in feather length can affect certain body regions or the entire plumage. Variations in feather structure (e.g., silkiness, frilled feathering) can be found in exhibition poultry as well as in pet birds. Variations in feather arrangement (e.g., feather crests and vortices) occur in many domesticated bird species as a results of mutation and intense selective breeding. The causes of variations in the structure, distribution, length and arrangement of feathers is often unknown and opens a wide field for scientific research under various points of view (e.g., morphogenesis, pathogenesis, ethology, etc.). To that extent, variations in the morphology, distribution and arrangement of feathers in domesticated birds require also a concern for animal welfare because certain alleles responsible for integumentary variations in domesticated birds have pleiotropic effects, which often affect normal behaviour and viability.  相似文献   

4.
Keratinophilic fungi were isolated from feathers of most common Indian birds,viz. domestic chicken (Gallus domesticus), domestic pigeon (Columba livia), house sparrow (Passer domesticus), house crow (Corvus splendens), duck (Anas sp.), rose-ringed parakeet (Psittacula krameri). Out of 87 birds, 58 yielded 4 keratinophilic fungal genera representing 13 fungal species and one sterile mycelium. The isolated fungi were cultured on Sabouraud's dextrose agar at 28±2°C.Chrysosporium species were isolated on most of the birds.Chrysosporium lucknowense andChrysosporium tropicum were the most common fungal species associated with these Indian birds. Maximum occurrence of fungi (47%) was recorded on domestic chickens and the least number of keratinophilic fungi was isolated from the domestic pigeon and duck. The average number of fungi per bird was found to be the 0.44.  相似文献   

5.
6.
Birds often lose feathers during predation attempts, and thisability has evolved as a means of escape. Because predatorsare more likely to grab feathers on the rump and the back thanon the ventral side of an escaping bird, we predicted that theformer feathers would have evolved to be relatively looselyattached as an antipredator strategy in species that frequentlydie from predation. We estimated the force required to removefeathers from the rump, back, and breast by pulling featherswith a spring balance from a range of European bird speciesin an attempt to investigate ecological factors associated withease of feather loss during predation attempts. The force requiredto loosen a feather from the rump was less than that requiredto loosen a feather from back, which in turn was less than thatrequired to loosen a feather from the breast. The relative forceneeded to loosen rump feathers compared with feathers from theback and the breast was smaller for prey species preferred bythe most common predator of small passerine birds, the sparrowhawkAccipiter nisus. Likewise, the relative force was also smallerin species with a high frequency of complete tail loss amongfree-living birds, which we used as an index of the frequencyof failed predation attempts. The relative force required toremove feathers from the rump was smaller in species with ahigh frequency of fear screams, another measure of the relativeimportance of predation as a cause of death. Feather loss requiredparticularly little force among solitarily breeding bird speciesthat suffer the highest degree of predation. Antipredator defensein terms of force required to remove feathers from the rumpwas larger in species with a strong antiparasite defense interms of T-cell–mediated immune response. These findingsare consistent with the hypothesis that different defenses areantagonistic and that they are traded off against each other.  相似文献   

7.
Freed LA  Cann RL 《PloS one》2012,7(1):e29834
Food limitation greatly affects bird breeding performance, but the effect of nutritive stress on molt has barely been investigated outside of laboratory settings. Here we show changes in molting patterns for an entire native Hawaiian bird community at 1650-1900 m elevation on the Island of Hawaii between 1989-1999 and 2000-2006, associated with severe food limitation throughout the year beginning in 2000. Young birds and adults of all species took longer to complete their molt, including months never or rarely used during the 1989-1999 decade. These included the cold winter months and even the early months of the following breeding season. In addition, more adults of most species initiated their molt one to two months earlier, during the breeding season. Suspended molt, indicated by birds temporarily not molting primary flight feathers during the months of peak primary molt, increased in prevalence. Food limitation reached the point where individuals of all species had asymmetric molt, with different primary flight feathers molted on each wing. These multiple changes in molt, unprecedented in birds, had survival consequences. Adult birds captured during January to March, 2000-2004, had lower survival in four of five species with little effect of extended molt. Extended molt may be adaptive for a nutrient stressed bird to survive warm temperatures but not cool winter temperatures that may obliterate the energy savings. The changing molt of Hawaiian birds has many implications for conservation and for understanding life history aspects of molt of tropical birds.  相似文献   

8.
Rijke, A.M., Jesser, W.A., Evans, S.W & Bouwman, H. 2000. Water repellency and feather structure of the Blue Swallow Hirundo atrocaerulea. Ostrich 71 (1 & 2): 143–145.

The Blue Swallow is an endangered species in southern Africa and is probably the most endangered passerine. It is restricted to escarpments with grasslands above 1 000 m where mists are frequent. It appears to forage on the wing even in thick mist raising the question of feather wettability in relation to its adaptation. Extensive physical and behaviourial adaptations are known to occur in a wide variety of birds to deal with the problem of shedding water continuously. To study the water repellency and resistance to water penetration of Blue Swallow feathers, we have examined the microscopic structure of head, back, throat, breast and abdominal feathers as well as remiges and tail feathers by transmission light microscopy. The width (2R) and separation (2D) of rami and barbules have been measured and were used to calculate the parameter (R + D)/R that serves as an indicator ofwater shedding potential. For the remiges and tail feathers the values of the (R+D)/R range from 5 to 10 which is comparable to values for other terrestrial birds. However, for body feathers the range is from 10 (head) and 35 (abdomen)-higher than previously observed for any other bird including Swifts, Apodidae. Blue Swallow feathers are thus the most effective feather yet discovered at repelling water drops. The water repellency is highest in those feathers that are relatively shielded From the direct impact of small water drops (throat, breast, abdomen, back). By contrast, the flight feathers must possess a relatively large resistance to water penetration to avoid becoming waterlogged and this is coupled to low (R+D)/R values. Values for the barbules lay between 2 and 6—the same as found for other bird families—supporting an earlier conclusion that they have little direct effect in repelling water.  相似文献   

9.
THOS A. BATTEN 《Ostrich》2013,84(2):92-94
Harrison, C. J. O. 1980. Fossil birds from Afrotropical Africa in the collection of the British Museum (Natural History). Ostrich 51:92-98.

Although it has a rich avifauna, few fossil birds are know from Africa south of the Sahara. In the present paper 22 species are identified from three Miocene and two Pleistocene localities, 20 being additions to the existing list. A new touraco Apopempsis africanus sp. nov. is described from the Lower Miocene of Songhor, Kenya; and from the same period on Rusinga Island, Kenya, a new stork Ciconia minor sp. nov., in addition to a small flamingo, a hawk and a francol-in. There is evidence of a bustard and a Ciconia stork from the Middle Miocene of Maboko Island, Kenya. In the Pleistocene nine species are listed for Olduvai, Tanzania, and seven for Broken Hill, Zambia. There is some evidence of a shared Afro-tropicai/Palaearctic fuana in the Miocene, and of a larger inland lake bird fauna in the Early Pleistocene of Olduvai, but the Broken Hill material is purely Afrotropical.  相似文献   

10.
Agricultural habitats are assumed to be biodiversity refuges. However, some studies treat agricultural land management as a cause of the biodiversity decline, to which habitat loss and heterogeneity may contribute. Between the crops, the successional habitats appear – ruderal plant communities and bush areas. Their influence on farmland biodiversity is unknown. This research assessed the impact of spatial relationships between agricultural areas, semi-natural meadows and successional habitats on the bird species richness, Shannon diversity index, and Faith’s phylogenetic diversity index. An additional habitat variable was the presence of weeds, i.e., invasive Caucasian hogweeds Heracleum sp., treated as crops in the past. The birds and habitats research was on 74 sites set in pairs (invaded vs control) in south-eastern Poland. Results showed that birds assembling in agricultural and semi-natural areas were more diverse and contained protected farmland species, while birds appearing in overgrown habitats (i.e., successional and invaded) were clumped with their habitat requirements. In the presence of plant invaders, ruderal habitats negatively affected the bird phylogenetic diversity index. In invaded sites, bush areas had no positive effects on the Shannon diversity index and species richness of birds, in contrast with control sites. The presented research suggests the need to re-evaluate the importance of successional non-crop habitats considered positive in agricultural landscapes if those habitats develop in areas with plant invasion.  相似文献   

11.
中国中生代的鸟类:介绍及综述   总被引:4,自引:0,他引:4  
周忠和  张福成 《动物学报》2004,50(6):913-920
最近十来年 ,中国辽宁发现的早白垩世的鸟类化石超过了世界上其它任何一个地区。中国的中生代鸟类化石代表了始祖鸟化石之后鸟类历史上第一次显著的分异。它们不仅包括了带有明显恐龙祖先特征的长尾的鸟类 ,而且还包括了许多进步或特化的种类 ,如早白垩世最大的鸟类 ,最原始的反鸟类 ,以及保存最好的、飞行结构和现生鸟类几乎一样的今鸟类。这些早期鸟类在诸如飞行、大小和食性等所反映的演化、形态和生态学特征等方面出现了重大的分异。具有长尾骨骼的原始基干鸟类热河鸟和驰龙类具有的相似性 ,进一步支持了鸟类起源于恐龙的学说。中国发现的早白垩世的鸟类以及树栖的恐龙化石还为鸟类飞行的树栖起源假说提供了十分重要的证据。“恐龙下树”的假说结合了鸟类起源于恐龙的学说和鸟类飞行的树栖起源学说 ,因此也得到了化石证据的支持。由于多种恐龙带有羽毛 ,因此羽毛不一定代表了恒温。恒温的鸟类可能到了早白垩世的进步鸟类中才开始出现  相似文献   

12.
Fungi isolated from Antarctic material   总被引:1,自引:1,他引:0  
Summary Fungi isolated from samples of soil, penguin, skua and petrel dung and bird feathers in the Victoria Land, Antarctica, from Inexpressible Island to Cape King, were studied. All material was collected in December 1987–January 1988. Fungi occurred prevalently in bird dung and in soil, especially when mosses were present. The main species isolated were: the keratinophilic Chrysosporium verrucosum and Geomyces pannorum var. pannorum, Phoma herbarum and Thelebolus microsporus. A variety of filamentous fungi and yeasts were also encountered in soil, dung and bird feathers samples in different localities: Acremonium strictum, Cladosporium herbarum, Scolecobasidium salinum, Mortierella antarctica, Paecilomyces farinosus, Phialophora fastigiata, the thermophilic Scytalidium thermophile and Thermomyces lanuginosus, Verticillium sp., Mycelia sterilia and Cryptococcus albidus and Torulaspora delbrueckii. Most of the fungal isolates appeared to be cold-tolerant. Results from this study are discussed in conjuction with data from previous Antarctic studies in this area.  相似文献   

13.
Aim Conservation programmes for endangered migratory species or populations require locating and evaluating breeding, stopover and wintering areas. We used multiple stable isotopes in two endangered European populations of wrynecks, Jynx torquilla L., to locate wintering regions and assess the degree of migratory connectivity between breeding and wintering populations. Location Switzerland and Germany. Methods We analysed stable nitrogen (δ15N), carbon (δ13C) and hydrogen (δD) isotopes from wing feathers from two populations of wrynecks to infer their wintering origins and to assess the strength of migratory connectivity. We tested whether variation in feather isotopic values within the Swiss population was affected by bird age and collection year and then considered differences in isotopic values between the two breeding populations. We used isotopic values of summer‐ and winter‐grown feathers to estimate seasonal distributions. Finally, we calculated a species‐specific δD discrimination factor between feathers and mean annual δD values to assign winter‐grown feathers to origin. Results Bird age and collection year caused substantial isotopic variation in winter‐grown feathers, which may be because of annually variable weather conditions, movements of birds among wintering sites and/or reflect asynchronous moulting or selection pressure. The large isotopic variance in winter‐grown feathers nevertheless suggested low migratory connectivity for each breeding population, with partially overlapping wintering regions for the two populations. Main conclusions Isotopic variance in winter‐grown feathers of two breeding populations of wrynecks and their geographical assignment point to defined, albeit overlapping, wintering areas, suggesting both leapfrog migration and low migratory connectivity. On this basis, integrative demographic models can be built looking at seasonal survival patterns with links to local environmental conditions on both breeding and wintering grounds, which may elucidate causes of declines in migratory bird species.  相似文献   

14.
Body feathers are important to many interactions birds have with their physical and social environments, such as streamlining the body for flight, thermoregulation, and social signaling. Birds differ dramatically in the texture of their body plumage depending on species and age class, likely reflecting different functional demands and age‐related trade‐offs in feather production. Despite the important insights potentially offered by studying variation in the structure of body feathers, there is no clear system for quantifying this variation. We present methods for quantifying age and species differences in the structure of body feathers. Most variation in our measures is due to species and age‐class differences, with little variance attributable to individual birds or to differences among feathers sampled from the same bird. We use our measures to test the hypothesis that the loosely‐textured plumage characteristic of many juvenile passerines reflects a trade‐off between investment in feather quality and rapid body growth that promotes early fledging. The structure of juvenile feathers was negatively correlated with duration of the nestling period among ten species of New World warblers (Parulidae), suggesting a trade‐off between investment in feathers and investment in rapid somatic development promoting fledging. Systematic studies of variation in the structure of body feathers will likely offer numerous other insights into avian biology.  相似文献   

15.
Ectoparasites, particularly chewing lice in the Phthiraptera (Insecta), affect the ecology of numerous host species. Most lice are highly host-specific, and there are no documented cases of major increases of chewing lice, within populations, over years. During continuous study from 1987-2005 at upper elevation forests on the island of Hawaii, chewing lice were exceedingly rare and, until 2003, were found in just 2 of 12 species of native and introduced birds. From 2003-2005, there was an explosive increase in the prevalence of chewing lice in all host species. There was no change in humidity, or in behavior of hosts, that could have caused an ecological release of existing lice. Based on reduced fat levels and increases in broken wing and tail feathers for most host species, there was apparently a food limitation that preceded the increase. The increase coincided temporally with detection of a nonnative bird that had recently been found in elevations below the study sites. Although there were isolated sightings of this bird on the study sites, seasonal movements and behavior of some species of native birds could also have allowed greater transmission to study sites. Both prevalence and intensity of infection, indexed by number of body regions parasitized, were lower in native species with greater bill overlap, a character that could help birds control lice. Seasonality of prevalence indicated that low prevalence preceded molt and high prevalence occurred after molting of hosts. The number of major fault bars in wing and tail feathers, a sign of nutritive stress, was correlated with intensity of infection, indicating an indirect cost to the hosts of being parasitized. In addition, birds with lice were less likely to be recaptured than birds without lice.  相似文献   

16.
Parasites and other symbionts are crucial components of ecosystems, regulating host populations and supporting food webs. However, most symbiont systems, especially those involving commensals and mutualists, are relatively poorly understood. In this study, we have investigated the nature of the symbiotic relationship between birds and their most abundant and diverse ectosymbionts: the vane‐dwelling feather mites. For this purpose, we studied the diet of feather mites using two complementary methods. First, we used light microscopy to examine the gut contents of 1,300 individual feather mites representing 100 mite genera (18 families) from 190 bird species belonging to 72 families and 19 orders. Second, we used high‐throughput sequencing (HTS) and DNA metabarcoding to determine gut contents from 1,833 individual mites of 18 species inhabiting 18 bird species. Results showed fungi and potentially bacteria as the main food resources for feather mites (apart from potential bird uropygial gland oil). Diatoms and plant matter appeared as rare food resources for feather mites. Importantly, we did not find any evidence of feather mites feeding upon bird resources (e.g., blood, skin) other than potentially uropygial gland oil. In addition, we found a high prevalence of both keratinophilic and pathogenic fungal taxa in the feather mite species examined. Altogether, our results shed light on the long‐standing question of the nature of the relationship between birds and their vane‐dwelling feather mites, supporting previous evidence for a commensalistic–mutualistic role of feather mites, which are revealed as likely fungivore–microbivore–detritivore symbionts of bird feathers.  相似文献   

17.
净月潭地区土壤螨类及其群落生态学研究   总被引:13,自引:2,他引:13  
卜照义 《生态学报》1990,10(4):355-361
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18.
Seven of the ten Liphistius species already known from Thailand and Burma are characterized; three new species, L. lannaianus sp.n., L. marginatus sp.n., L. thaleban sp.n., and the males of L. lordac Platnick & Scdgwiek and L. niphanae Ono are described. Taxonomy and relationships are discussed; considerable variation in female internal genitalia is shown. Notes are given on natural history, distribution, burrow structure, phenology and behaviour.  相似文献   

19.
We investigated whether trace elements in tail feathers of an insectivorous and long-distance migratory bird species could be used to identify moulting areas and hence migratory pathways. We analysed tail feathers from birds of different age and sex collected from a range of different breeding sites across Europe. The site of moult had a large effect on elemental composition of feathers of birds, both at the European and African moulting sites. Analysis of feathers of nestlings with known origin suggested that the elemental composition of feathers depended largely upon the micro-geographical location of the colony. The distance between moulting areas could not explain the level of differences in trace elements. Analysis of feathers grown by the same individuals on the African wintering grounds and in the following breeding season in Europe showed a large difference in composition indicating that moulting site affects elemental composition. Tail feathers moulted in winter in Africa by adults breeding in different European regions differed markedly in elemental composition, indicating that they used different moulting areas. Analysis of tail feathers of the same adult individuals in two consecutive years showed that sand martins in their first and second wintering season grew feathers with largely similar elemental composition, although the amounts of several elements in tail feathers of the older birds was lower. There was no difference between the sexes in the elemental composition of their feathers grown in Africa. Investigation of the trace element composition of feathers could be a useful method for studying similarity among groups of individuals in their use of moulting areas.  相似文献   

20.
A synoptic review of the discoveries and studies of Chinese Mesozoic birds is provided in this paper.40Ar/39Ar dating of several bird-bearing deposits in the Jehol Group has established a geochronological framework for the study of the early avian radiation.Chinese Mesozoic birds had lasted for at least 11 Ma during about 131 Ma and 120 Ma (Barremian to Aptian)of the middle and late Early Cretaceous,respectively.In order to further evaluate the change of the avian diversity in the Jehol Biota,six new orders and families are erected based on known genera and species,which brings the total number of orders of Chinese Mesozoic birds to 15 and highlights a remarkable radiation ever since the first appearante of birds in the Late Jurassic.Chinese Early Cretaceous birds had experienced a significant differentiation in morphology,flight,diet and habitat.Further examination of the foot of Jeholornis suggests this bird might not have possessed a fully reversed hallux.However,the attachment of metatarsal Ⅰ to the medial side of metatarsal Ⅱ does not preclude trunk climbing,a pre-adaptation for well developed perching life of early birds.Arboreality had proved to be a key adaptation in the origin and early evolution of bird flight,and the adaptation to lakeshore environment had played an equally important role in the origin of omithurine birds and their near-modern flight skill.Many Chinese Early Cretaceous birds had preserved the direct evidence of their diet,showing that the most primitive birds were probably mainly insectivorous and that specialized herbivorous or carnivorous (e.g.,piscivorous)dietary adaptation had appeared only in later advanced forms.The only known Early Cretaceous bird embryo fossil has shown that precocial birds had occurred prior to altricial birds in avian history,and the size of the embryo and other analysis indicate it probably had a short incubation period.Leg feathers probably have a wide range of distribution in early birds,further suggesting that leg feathers had played a key role in the beginning stage of the flight of birds.Finally,the Early Cretaceous avian radiation can be better understood against the background of their unique ecosystem.The advantage of birds in the competitions with other vertebrate groups such as pterosaurs had probably not only resulted in the rapid differentiation and radiation of birds but also the worldwide spreading of pterosaurs and other vertebrates from East Asia in the Early Cretaceous.  相似文献   

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