Production of extracellular keratinases by keratinophilic fungal species inhabiting feathers of living poultry birds (Gallus domesticus): A comparison

Fourteen species of keratinophilic fungi belonging to ten genera (Chrysoporium, Malbranchea, Chaetomium,Sepedonium, Microascus, Scopulariopsis, Curvularia, Fusarium, Aspergillus, Penicillium) were isolated from feathers of about one hundred living poultry birds. The isolated fungi were compared for their keratinase activity after growing them on two different media: (1) basal salts solution containing natural keratin (human hair) as the only source of carbon and nitrogen; (2) the medium was supplemented with a minor amount of readily assimilable source of carbon along with natural keratin. All the test fungi could grow on keratinous material, degrading it and releasing sulphydryl containing compounds detected as cysteine, total proteins and extracellular keratinase. Maximum enzyme release by these fungi occurred in the broth supplemented with glucose and vitamins, thereby indicating a correlation between the mycelial biomass and production of proteolytic keratinases. This revised version was published online in June 2006 with corrections to the Cover Date.     

Moving Window Abundance – A method to characterise the abundance dynamics of farmland birds: The example of Skylark (Alauda arvensis)

Farmland birds are important indicators of the state of biodiversity in rural landscapes, and the occurrence and abundance of birds contribute to their importance as bioindicators. However, the measurement of farmland bird abundance can be difficult. The rapid growth of crop plants in the spring combined with disturbances related to farming practices, such as weed and pest control and other measures, can profoundly change the habitat suitability of arable fields for birds within a short period of time. Consequently, the existing dynamics must be incorporated into the applied methods, and a single value of bird abundance during the breeding season is insufficient to characterise the habitat functions of arable land. The abundance of farmland bird species is influenced by crop specific features, which profoundly change within the breeding season and which we have described using a novel concept called Moving Window Abundance. Based on field surveys in 29 observation areas within arable landscapes, each 1 km², Skylark with territorial behaviour were counted using a mapping method related to the habitats and growth of field crops, such as wheat and maize. To describe the dynamic characteristics of the abundance during the breeding season over the time period from 16 March to 18 July, three methods of Moving Window Abundance were tested: patchy, adjacent and overlapping. These methods differ in the time-space continuity of the considered time window throughout the breeding season. In the Patchy Moving Window Abundance method, we used the exact days in which field surveys were conducted throughout the entire time period of the field surveys. However, with the Adjacent Moving Window Abundance method, the time window included five-day, ten-day and semi-monthly adjacent windows; in the Overlapping Moving Window Abundance method, the time window shifted daily, with five-day, ten-day and semi-monthly overlapping windows used in the calculation procedure. The results indicated that the dynamic nature of Skylark abundance (i) reached a maximum level in the first breeding period in the agricultural landscape and (ii) exhibited large variations in level and time within the various field crops. Therefore, abundance was not described conventionally using a single numerical value but rather using mathematical functions based on the spatial scale of the landscape and habitat. We conclude with recommendations for further research to standardise farmland bird monitoring.     

Foraging ecology of the Great Crested Grebe (Podiceps cristatus L.) at a mesotrophic-eutrophic reservoir

The foraging ecology of the Great Crested Grebe wasstudied at Dobczyce Reservoir in southernPoland. The mean diving frequency of grebes withoutyoung was 19.3 h^–1, while grebes with young dived onaverage 32.5 h^–1. The mean number of apparent prey caughtby grebes without young was 0.5 fish h^–1. Birds with young caught a greater number, on average4.5 fish h^–1. Probably, birds fishing forthemselves ate much prey underwater. The total lengthof the fish consumed by adult grebes was on average10.0 cm. Adults ate larger fish in the breeding seasonthan in the autumn migration period. Young birds werefed fish about 8.3 cm long. More than 50% of preywere bleak. The mean success of dives of birds withoutyoung was 3.3% and for individuals with young 14.8%.A comparison of the weight of the daily food demandwith the weight of fish brought to the surface showed that it was 70% lower than the dailyfood demand. The poor relation between prey size anddiving success shows that grebes can eat both small andlarge fish below the water surface.     

The diet of early birds based on modern and fossil evidence and a new framework for its reconstruction

Birds are some of the most diverse organisms on Earth, with species inhabiting a wide variety of niches across every major biome. As such, birds are vital to our understanding of modern ecosystems. Unfortunately, our understanding of the evolutionary history of modern ecosystems is hampered by knowledge gaps in the origin of modern bird diversity and ecosystem ecology. A crucial part of addressing these shortcomings is improving our understanding of the earliest birds, the non-avian avialans (i.e. non-crown birds), particularly of their diet. The diet of non-avian avialans has been a matter of debate, in large part because of the ambiguous qualitative approaches that have been used to reconstruct it. Here we review methods for determining diet in modern and fossil avians (i.e. crown birds) as well as non-avian theropods, and comment on their usefulness when applied to non-avian avialans. We use this to propose a set of comparable, quantitative approaches to ascertain fossil bird diet and on this basis provide a consensus of what we currently know about fossil bird diet. While no single approach can precisely predict diet in birds, each can exclude some diets and narrow the dietary possibilities. We recommend combining (i) dental microwear, (ii) landmark-based muscular reconstruction, (iii) stable isotope geochemistry, (iv) body mass estimations, (v) traditional and/or geometric morphometric analysis, (vi) lever modelling, and (vii) finite element analysis to reconstruct fossil bird diet accurately. Our review provides specific methodologies to implement each approach and discusses complications future researchers should keep in mind. We note that current forms of assessment of dental mesowear, skull traditional morphometrics, geometric morphometrics, and certain stable isotope systems have yet to be proven effective at discerning fossil bird diet. On this basis we report the current state of knowledge of non-avian avialan diet which remains very incomplete. The ancestral dietary condition in non-avian avialans remains unclear due to scarce data and contradictory evidence in Archaeopteryx. Among early non-avian pygostylians, Confuciusornis has finite element analysis and mechanical advantage evidence pointing to herbivory, whilst Sapeornis only has mechanical advantage evidence indicating granivory, agreeing with fossilised ingested material known for this taxon. The enantiornithine ornithothoracine Shenqiornis has mechanical advantage and pedal morphometric evidence pointing to carnivory. In the hongshanornithid ornithuromorph Hongshanornis only mechanical advantage evidence indicates granivory, but this agrees with evidence of gastrolith ingestion in this taxon. Mechanical advantage and ingested fish support carnivory in the songlingornithid ornithuromorph Yanornis. Due to the sparsity of robust dietary assignments, no clear trends in non-avian avialan dietary evolution have yet emerged. Dietary diversity seems to increase through time, but this is a preservational bias associated with a predominance of data from the Early Cretaceous Jehol Lagerstätte. With this new framework and our synthesis of the current knowledge of non-avian avialan diet, we expect dietary knowledge and evolutionary trends to become much clearer in the coming years, especially as fossils from other locations and climates are found. This will allow for a deeper and more robust understanding of the role birds played in Mesozoic ecosystems and how this developed into their pivotal role in modern ecosystems.     

Introgression of Allium fistulosum into A. cepa mediated by A. roylei

Introgression of Allium fistulosum into the genome of A. cepa using A. roylei as a bridging species was studied by means of genomic in situ hybridization (GISH). Here we demonstrate for the first time that A. fistulosum can be stably introgressed into A. cepa with a bridge-cross. The first and second bridge-cross generations were fertile, although pollen was sterile in some individuals. Only occasionally were there translocations in the second generation bridge-cross. Recombination between the three genomes was frequently seen in meiotic anaphase 1 and prophase 2 chromosomes of the first generation bridge cross and in mitotic chromosomes of the second generation bridge-cross. The number of observed recombination points in anaphase 1 and prophase 2 significantly exceeded the value expected from chiasma frequency in metaphase 1. Recombination points were randomly distributed, thus the A. cepa or A. roylei type of random distribution prevails over the A. fistulosum type of proximally localised chiasmata. Received: 15 December 1998 / Accepted: 18 February 1999     

Interspecific comparison of the fecal microbiota structure in three Arctic migratory bird species

The gut microbiota of birds is known to be characterized for different species, although it may change with feeding items. In this study, we compared the gut microbiota of birds with different feeding behaviors in the same habitat. We collected fecal samples from three Arctic species, snow buntings Plectrophenax nivalis, sanderlings Calidris alba, and pink‐footed geese Anser brachyrhynchus that are phylogenetically quite distant in different families to evaluate effects of diet on gut microbiota. Also, we characterized the prevalence of fecal bacteria using the Illumina MiSeq platform to sequence bacterial 16S rRNA genes. Our NMDS results showed that fecal bacteria of snow buntings and sanderlings were significantly distant from those of pink‐footed geese. Although all three birds were occupied by three bacterial phyla, Proteobacteria, Firmicutes, and Bacteroidetes, dominant taxa still varied among the species. Our bacterial sequences showed that snow buntings and sanderlings were dominated by Firmicutes and Bacteroidetes, while pink‐footed geese were dominated by Proteobacteria. In addition, the bacterial diversity in snow buntings and sanderlings was significantly higher than that in pink‐footed geese. Our results suggest that insectivorous feeding diet of snow buntings and sanderlings could be responsible for the similar bacterial communities between the two species despite the distant phylogenetic relationship. The distinctive bacterial community in pink‐footed geese was discussed to be related with their herbivorous diet.     

Phenological relationships of wasps, bumblebees, their mimics and insectivorous birs in northern Michigan

Abstract. 1. In northern Michigan 72% of the high fidelity dipterous Batesian mimics of bumblebees and vespoid wasps occurred in spring while they still outnumbered their models but before the great majority of fledgling birds left their nests to begin foraging for insects on their own.
2. This extends the known occurrence of this sort of phenology to several additional mimetic species and to an area which is radically different climatically and ecologically from the central Illinois areas in which this sort of phenology was first noted.
3. Our observations confirm the hypothesis that Batesian mimics may be selected to avoid the midsummer period when newly fledged insectivorous birds are abundant but have not yet learned to shun their stinging hymenopteran models.
4. The shortness of the warm season in Michigan reduces opportunities for temporal separation and may have forced the other 28% of the high fidelity mimics to occur when naive birds are abundant. The threat from naive birds was, however, presumably somewhat ameliorated by the abundance of models at that time.     

Amino acid sequences of ovomucoid third domains from 27 additional species of birds

Ovomucoids consist of a single polypeptide chain which is composed of three tandem Kazal domains. Each Kazal domain is an actual or putative protein inhibitor of serine proteinases. Ovomucoid third domains were already isolated and sequenced from 126 species of birds (Laskowskiet al., 1987, 1990). This paper adds 27 new species. A number of generalizations are made on the basis of sequences from 153 species. The residues that are in contact with the enzyme in enzyme-inhibitor complexes are strikingly hypervariable. While the primary specificity residue,P ₁, is the most variable; substitutions occur predominantly among aliphatic, hydrophobic residues. Consensus sequences for an avian ovomucoid third domain, for a b-type Kazal domain (i.e., a COOH terminal domain of multidomain inhibitors) and for a general Kazal domain are given. Finally, the individual new sequences are briefly discussed.     

A multispecies BCO2 beak color polymorphism in the Darwin’s finch radiation

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