Heterospecific sociality of birds on beaches from southeastern Brazil

Studies on the sociality of heterospecific assemblages of birds have promoted a greater understanding of the types of interactions and survivorship between coexisting species. This study verified the group compositions in bird assemblages and analyzed the sociality of migratory and resident species on sandy beaches of southeastern Brazil. A transect was established on the median portion of beaches and all the groups of bird species (monospecific, heterospecific) and solitary individuals were registered four days per month from November 2006 to April 2007. The sociality of each species was calculated by its frequency in heterospecific groups, its proportional number of contacts with other species in heterospecific groups, and the number of species that it associated with. Semipalmated Sandpiper Calidris pusilla (Linnaeus, 1766) and Semipalmated Plover Charadrius semipalmatus Bonaparte, 1825 (both migratory) had the highest degree of sociality and did not show a preference to associate with either residents or migratory species. Sanderling Calidris alba (Pallas, 1764) (migratory) occupied the third position in the sociality rank and associated with migratory species frequently. Southern Caracara Carara plancus (Miller, 1777) and Black Vulture Coragyps atratus (Beschstein, 1793) (both resident) were uniquely found among heterospecific groups with necrophagous and resident species. Kelp Gull Larus dominicanus Lichtenstein, 1823 (resident) associated more frequently with resident species. The sociality in assemblages of birds may promote advantages such as an increased collective awareness in dangerous situations and indication of sites with abundant food sources.

A butterfly eye's view of birds

The striking color patterns of butterflies and birds have long interested biologists. But how these animals see color is less well understood. Opsins are the protein components of the visual pigments of the eye. Color vision has evolved in butterflies through opsin gene duplications, through positive selection at individual opsin loci, and by the use of filtering pigments. By contrast, birds have retained the same opsin complement present in early-jawed vertebrates, and their visual system has diversified primarily through tuning of the short-wavelength-sensitive photoreceptors, rather than by opsin duplication or the use of filtering elements. Butterflies and birds have evolved photoreceptors that might use some of the same amino acid sites for generating similar spectral phenotypes across approximately 540 million years of evolution, when rhabdomeric and ciliary-type opsins radiated during the early Cambrian period. Considering the similarities between the two taxa, it is surprising that the eyes of birds are not more diverse. Additional taxonomic sampling of birds may help clarify this mystery.

The rise of birds and mammals: are microevolutionary processes sufficient for macroevolution?

It is a basis of darwinian evolution that the microevolutionary mechanisms that can be studied in the present are sufficient to account for macroevolution. However, this idea needs to be tested explicitly, as highlighted here by the example of the superceding of dinosaurs and pterosaurs by birds and placental mammals that occurred near the Cretaceous/Tertiary boundary approximately 65 million years ago. A major problem for testing the sufficiency of microevolutionary processes is that independent ideas (such as the existence of an extraterrestrial impact, and the extinction of dinosaurs) were linked without the evidence for each idea being evaluated separately. Here, we suggest and discuss five testable models for the times and divergences of modern mammals and birds. Determination of the model that best represents these events will enable the role of microevolutionary mechanisms to be evaluated. The question of the sufficiency of microevolutionary processes for macroevolution is solvable, and available evidence supports an important role for biological processes in the initial decline of dinosaurs and pterosaurs.

Some Reflections on the Emergence of Multimodal Assemblages of Meaning

In this commentary I reflect upon the conceptualisation of human meaning-making, utilised in the two target articles, that relies heavily on speech as the main mode of semiosis and considers time only in its chronological form. Instead I argue that human existence is embodied and lived through multiple modalities, and involves not only sequential experience of time, but also experience of emergence. In order to move towards a conception of meaning-making that takes this into account, I introduce the social-semiotic theory of multimodality (Kress 2010) and discuss notions of ‘real duration’ (Bergson 1907/1998) and ‘lived time’ (Martin-Vallas 2009). I argue that dialogical (idiographic) researchers need to develop analytic and methodological tools that allow exploring the emergence of multimodal assemblages of meaning in addition to trying to avoid the monologisation of complex dynamic dialogical phenomena.

Bricolage and storied selves: Young people's assemblages of narrative and identity in an Australian life storytelling project

Narrating is simultaneously self-interpretation and self-construction. People make sense of their lives and create their identities through an active process of assembling and applying meaning to memories, experiences, thoughts, actions and passions. Such a process can usefully be described as a bricolage: life narratives are created as an assemblage of scattered experiences and events. Through the particular way in which they are arranged, the storyteller constructs what Paul Ricoeur (1992) calls a “narrative identity”; that is, an identity which is organised through and specific to the story told. Applying this notion of narrative as bricolage to ‘Heywire’ – an Australian youth life storytelling project – this paper discusses the unique affordances that the process of storytelling offers in terms of identity and the way new, digital technologies and the internet augment the features of life narratives. It argues that narrative, in addition to new media, offers important tools through which young people who participate in the Heywire project make sense of personal experiences and craft their own identities in powerful and purposeful ways.

Mapping and characterisation of the inter-reefal benthic assemblages of the Torres Strait

A comprehensive survey of the benthic assemblages of the Torres Strait was conducted in order to provide critical baseline information for regional marine planning, assessing the environmental sustainability of fisheries and understanding the ecosystems of the region. Over 150 sites throughout the region were sampled with a modified prawn trawl, towed underwater video, pipe dredge and epibenthic sled. This manuscript provides a broad overview of the activities undertaken and data collected. Two thousand three hundred and seventy-two different nominal species were sampled by the trawl and sled, only 728 by both gears. The towed video was not able to provide the same level of taxonomic resolution of epibenthic taxa, but was particularly useful in areas where the seabed was too rough to be sampled. Data from the trawl, sled and video were combined to characterise the epibenthic assemblages of the region. Data from the towed video was also used to provide a characterisation of the inter-reefal benthic habitats, which was then analysed in combination with physical covariate data to examine relationships between the two. Levels of mud and gravel in the sediments, trawling effort and seabed current stress were the covariates most significantly correlated with the nature of the seabed habitats.

Phylogenetic relationships of unclassified, satellitic Pasteurellaceae obtained from different species of birds as demonstrated by 16S rRNA gene sequence comparison

Avian haemophili demonstrating in vitro satellitic growth, also referred to as the V-factor or NAD requirement, have mainly been classified with Avibacterium paragallinarum (Haemophilus paragallinarum), Avibacterium avium (Pasteurella avium), Avibacterium volantium (Pasteurella volantium) and Avibacterium sp. A (Pasteurella species A). The aim of the present study was to assess the taxonomic position of 18 V-factor-requiring isolates of unclassified Haemophilus-like organisms isolated from galliforme, anseriforme, columbiforme and gruiforme birds as well as kestrels and psittacine birds including budgerigars by conventional phenotypic tests and 16S rRNA gene sequencing. All isolates shared phenotypical characteristics which allowed classification with Pasteurellaceae. Haemolysis of bovine red blood cells was negative. Haemin (X-factor) was not required for growth. Maximum-likelihood phylogenetic analysis including bootstrap analysis showed that six isolates were related to the avian 16S rRNA group and were classified as Avibacterium according to 16S rRNA sequence analysis. Surprisingly, the other 12 isolates were unrelated to Avibacterium. Two isolates were unrelated to any of the known 16S rRNA groups of Pasteurellaceae. Two isolates were related to Volucribacter of the avian 16S rRNA group. Seven isolates belonged to the Testudinis 16S rRNA group and out of these, two isolates were closely related to taxa 14 and 32 of Bisgaard, whereas four other isolates were found to form a genus-like group distantly related to taxon 40 and one isolated remained distantly related to other members of the Testudinis group. One isolate was closely related to taxon 26 (a member of Actinobacillus sensu stricto). The study documented major genetic diversity among V-factor-requiring avian isolates beyond the traditional interpretation that they only belong to Avibacterium, underlining the limited value of satellitic growth for identification of avian members of Pasteurellaceae. Our study also emphasized that these organisms will never be isolated without the use of special media satisfying the V-factor requirement.

Spatial subdivision among assemblages of Spanish mackerel, Scomberomorus commerson (Pisces: Scombridae) across northern Australia: implications for fisheries management

Aim: This study investigated the use of stable δ13C and δ18O isotopes in the sagittal otolith carbonate of narrow-barred Spanish mackerel, Scomberomorus commerson, as indicators of population structure across Australia. Location: Samples were collected from 25 locations extending from the lower west coast of Western Australia (30°), across northern Australian waters, and to the east coast of Australia (18°) covering a coastline length of approximately 9500 km, including samples from Indonesia. Methods: The stable δ13C and δ18O isotopes in the sagittal otolith carbonate of S. commerson were analysed using standard mass spectrometric techniques. The isotope ratios across northern Australian subregions were subjected to an agglomerative hierarchical cluster analysis to define subregions. Isotope ratios within each of the subregions were compared to assess population structure across Australia. Results: Cluster analysis separated samples into four subregions: central Western Australia, north Western Australia, northern Australia and the Gulf of Carpentaria and eastern Australia. Isotope signatures for fish from a number of sampling sites from across Australia and Indonesia were significantly different, indicating population separation. No significant differences were found in otolith isotope ratios between sampling times (no temporal variation). Main conclusions: Significant differences in the isotopic signatures of S. commerson demonstrate that there is unlikely to be any substantial movement of fish among these spatially discrete adult assemblages. The lack of temporal variation among otolith isotope ratios indicates that S. commerson populations do not undergo longshore spatial shifts in distribution during their life history. The temporal persistence of spatially explicit stable isotopic signatures indicates that, at these spatial scales, the population units sampled comprise functionally distinct management units or separate ‘stocks’ for many of the purposes of fisheries management. The spatial subdivision evident among populations of S. commerson across northern and western Australia indicates that it may be advantageous to consider S. commerson population dynamics and fisheries management from a metapopulation perspective (at least at the regional level).

A landscape approach to conservation of birds

Landscape ecology as a discipline in science is rather young. However its principles appear promising in outlining conservation strategies including a wide range of organisms, particularly birds. Birds due to their mobility use a variety of environmental resources, especially habitats. However, currently these habitats are only available in patches over most of the tropical world. Further whatever is left is under constant human pressure. This paper, therefore, addresses this problem and suggests means of dealing with it using the landscape approach as outlined by landscape ecology. The landscape approach starts with the realization that patches of habitats are open and interact with one another. Corridors of trees along roads, hedgerows and canals in a landscape can aid in the movement of species. Hence the landscape approach considers patches of habitats as interacting elements in the large matrix of the landscape. The landscape approach also integrates concepts. It puts together often debated issues such as whether to preserve maximum species diversity, to maximize representativeness, or to preserve only the valuable species. Based on a case study of the Uttara Kannada district in Karnataka, these oft-opposing views and complications can be dealt with practically and synthesized into a conservation strategy far the diverse avifauna of the Western Chats.

Nestedness pattern in stream diatom assemblages of central Western Ghats

Community diversity and the population abundance of a particular group of species are controlled by immediate environment, inter-and intra-species interactions, landscape conditions, historical events and evolutionary processes. Nestedness is a measure of order in an ecological system, referring to the order in which the number of species is related to area or other factors. In this study we have studied the nestedness pattern in stream diatom assemblages in 24 stream sites of central Western Ghats, and report 98 taxa from the streams of central Western Ghats region. The communities show highly significant nested pattern. The Mantel test of matrix revealed a strong relationship between species assemblages and environmental conditions at the sites. A significant relationship between species assemblage and environmental condition was observed. Principal component analysis (PCA) indicated that environmental conditions differed markedly across the sampling sites, with the first three components explaining 78% of variance. Species composition of diatoms is significantly correlated with environmental distance across geographical extent. The current pattern suggests that micro-environment at regional levels influences the species composition of epilithic diatoms in streams. The nestedness shown by the diatom community was highly significant, even though it had a high proportion of idiosyncratic species, characterized with high numbers of cosmopolitan species, whereas the nested species were dominated by endemic species. PCA identifies ionic parameters and nutrients as the major features which determine the characteristics of the sampling sites. Hence the local water quality parameters are the major factors in deciding the diatom species assemblages.

Two new subspecies of birds from Panama

While working on the Smithsonian Biological Survey of the Canal Zone, Mr. E. A. Goldman of the Biological Survey, United States Department of Agriculture, collected specimens of two undescribed subspecies of birds which are characterized below. (Document contains 3 pages)

Descriptions of new genera, species and subspecies of birds from Panama, Colombia, and Ecuador

The first of January, 1912, E. A. Goldman, of the Biological Survey, Department of Agriculture, was again detailed on the Smithsonian Biological Survey of the Canal Zone. He returned to Panama in January and remained there until the last of June passing most of this period in collecting birds and mammals on the slopes of Mount Pirri on the Pacific side of eastern Panama, near the Colombian border...(Document contains 27 pages)

Two new subspecies of birds from the slopes of Mount Pirri, eastern Panama

The two subspecies described below were part of the rich collection made by E. A. Goldman in Eastern Panama, during the season of 1912, while engaged in the Smithsonian Biological Survey of Panama. Other new birds from this collection were described in a recent paper...(Document contains 4 pages)

A comparison between warm-water fish assemblages of Narragansett Bay and those of Long Island Sound waters

Fish species of warmwater origin appear in northeastern U.S. coastal waters in the late summer and remain until late fall when the temperate waters cool. The annual abundance and species composition of warm-water species is highly variable from year to year, and these variables may have effects on the trophic dynamics of this region. To understand this variability, records of warm-water fish occurrence were examined in two neighboring temperate areas, Narragansett Bay and Long Island Sound. The most abundant fish species were the same in both areas, and regional abundances peaked in both areas in the middle of September, four weeks after the maximum temperature in the middle of August. On average, abundance of warm-water species increased throughout the years sampled, although this increase can not be said to be exclusively related to temperature. Weekly mean temperatures between the two locations were highly correlated (r= 0.99; P<0.001). The warm-water fish faunas were distinctly different in annual abundances in the two areas for each species by year (1987–2000), and these differences ref lect the variability in the transport processes to temperate estuaries. The results reveal information on the abundance of warm-water fish in relation to trends toward warmer waters in these region