Ornament colour selection, visual contrast and the shape of colour preference functions in great bowerbirds, Chlamydera nuchalis

A male bowerbird visual signal includes his own plumage, a structure he  constructs out of plant material and coloured objects (ornaments) he places on or near the structure to make up the bower. Plumage and bower together are used to attract females for mating. Ornaments are known to contrast with plumage, bower structure and visual backgrounds in seven Australian bowerbird species (Endler et al. 2005, Evolution, 50, 1795-1818). We estimated the colour preferences in a wild population of great bowerbirds using artificially coloured objects widely spaced in bird colour space. We found that these birds prefer colours that contrast with their own plumage, the bower structure and the visual backgrounds adjacent to the bower, and that they have very strong dislikes for colours that are similar to their own plumage and to the visual backgrounds. The range of disliked colour hues was much narrower than the range of preferred hues, suggesting that the word 'preference' may be misleading. Preferences for colour are inherently multidimensional and should be studied in the context of their function.

Predicting the direction of ornament evolution in Trinidadian guppies (Poecilia reticulata)

Sexual selection is thought to be opposed by natural selection such that ornamental traits express a balance between these two antagonistic influences. Phenotypic variation among populations may indicate local shifts in this balance, or that different stable ‘solutions’ are possible, but testing these alternatives presents a major challenge. In the guppy (Poecilia reticulata), a small freshwater fish with male-limited ornamental coloration, these issues can be addressed by transplanting fish among sites of varying predation pressure, thus effectively manipulating the strength and nature of natural selection. Here, we contrast the evolutionary outcome of two such introductions conducted in the Trinidadian El Cedro and Aripo Rivers. We use sophisticated colour appraisal methods that account for full spectrum colour variation and which incorporate the very latest visual sensitivity data for guppies and their predators. Our data indicate that ornamentation evolved along different trajectories: whereas Aripo males evolved more numerous and/or larger orange, black and iridescent markings, El Cedro males only evolved more extensive and brighter iridescence. Examination of the El Cedro experiment also revealed little or no ornamental evolution at the control site over 29 years, which contrasts markedly with the rapid (approx. 2–3 years) changes reported for introduction populations. Finally, whole colour-pattern analysis suggested that the greatest visual difference between El Cedro introduction and control fish would be perceived by the two most salient viewers: guppies and the putatively dangerous predator Crenicichla alta. We discuss whether and how these evolutionary trajectories may result from founder effects, population-specific mate preferences and/or sensory drive.

Organization, decoration

While organizational decoration has been of interest to those who study organizational artefacts, we suggest four ways in which decoration is worthy of fuller attention in organizational studies. First, decoration, ornament and embellishment are not only what we see, but also what we do as managers, consultants, writers and designers of both physical and project spaces. Second, and drawing on the art/craft debate, we note that decoration occupies contested and even liminal aesthetic position and that ‘decorative art’ lies betwixt and between fine art and craft. Neither fully accepted nor fully marginalized, decoration is ‘only applied’ and embodies shifting tensions between form and function. Third, we review the particular negotiations of these tensions at the Bauhaus, a controversial and highly influential aesthetic organization in early 20th century Germany. Fourth, we suggest that decoration, like disorganization, provides a source of complication for organizational studies that are neither pure nor parsimonious.

The Great East Window of York Minster

This inquiry into the meaning behind the images of this vast stained glass window has uncovered a complex theology of the Mass; replies to Lollard 'heretics'; and has identified threats to the power of the Church at this critical time in English history at the beginning of the fifteenth century.

Chromatic interaction between egg pigmentation and skin chromatophores in the nuptial coloration of female two-spotted gobies

In two-spotted gobies (Gobiusculus flavescens Fabricius 1779), females develop an orange belly as they approach sexual maturity. Bright belly coloration is preferred by males and has been suggested to act as a female ornament. This coloration is unusual in that it originates partly from pigmentation of the abdominal skin but also from strongly pigmented gonads directly visible through the skin. In addition, females have been observed to temporarily become more colourful during courtship and competition. To understand how gonad and skin pigmentation interact in this nuptial coloration, the potential for colour modification via regulation of skin chromatophores was investigated. Noradrenaline caused aggregation of chromatophore pigment and was used to experimentally reduce the contribution of skin chromatophores to the nuptial coloration. Chromatophore pigment aggregation caused bellies to become less colourful and abdominal skin biopsies to become less colourful and more transparent. There was a strong positive relationship between belly coloration and the coloration of the underlying gonads. This shows that belly coloration honestly reflects egg pigmentation, mainly because the transparency of the abdominal skin allows other fish to see the gonads directly. Interestingly, when noradrenaline caused pigment to aggregate and thereby increased the transparency of the skin, the relationship between belly and gonad coloration weakened. We conclude that female G. flavescens have a potential to use skin chromatophores to rapidly alter their nuptial coloration, thereby affecting the efficacy with which information about gonad coloration is conveyed.

Does female nuptial coloration reflect egg carotenoids and clutch quality in the Two-Spotted Goby (Gobiusculus flavescens, Gobiidae)?

Summary

1 - Carotenoid-based ornamentation has often been suggested to signal mate quality, and species with such ornaments have frequently been used in studies of sexual selection.

2 - Female Gobiusculus flavescens (Two-Spotted Goby) develop colourful orange bellies during the breeding season. Belly coloration varies among mature females, and previous work has shown that nest-holding males prefer females with more colourful bellies. Because males invest heavily in offspring during incubation, the evolution of this preference can be explained if colourful females provide males with eggs of higher quality.

3 - We tested this hypothesis by allowing males to spawn with ‘colourful’ and ‘drab’ females and comparing parameters including egg carotenoid concentration, clutch size, hatchability and larval viability between groups. We also investigated relationships between egg carotenoid concentration and clutch quality parameters.

4 - Eggs from colourful females had significantly higher concentrations of total carotenoids than drab females, and photographically quantified belly coloration was a good predictor of egg carotenoid concentration.

5 - Colourful females produced slightly larger clutches, but female belly coloration was not related to any measure of clutch quality. In addition, there were no significant relationships between egg carotenoids and clutch quality. Females with high levels of egg carotenoids spawned slightly earlier, however, possibly because they were more ready to spawn or because of male mate choice.

6 - Our results call into question the generality of a causal link between egg carotenoids and offspring quality.

The design of architectural dialect and local identity as Islam strategy in promoting its thought in Indonesia

The design of mosques in Indonesia uses basic principal form of Hindu temple with its roof taking the form of layered pyramid (3, 5, 7). This architectural dialect design approach was effective in promoting Islam in most regions of the Indonesian Archipelago. The detailed explanation about architectural dialect will be elaborated in my full paper. This paper discuss about a friendly approach by using Hindu Building as mosque. It has given a greatly impact to the surrounding society to Accept new religion. Such temple-styled mosques have a history dating back to 1200 AD and form the basic inspiration for mosque designs in all parts of the country. The layered pyramid mosque’s architectural dialect design proves that architecture has played significant role in promoting Islamic doctrines in Indonesia. 85% of the total Indonesian population is Muslim. Based on these statistics, it is widely evident that the use of dialect design as a political strategy by Muslim scholars was effective in introducing and promoting Islamic ideologies in Indonesia. The strategy facilitated psychological acceptance of Islam by the local populations who were initially Hindu believers and were accustomed to the temple. Additionally, the design ensured the peaceful introduction and spread of Islam in the region. Moreover, the fact that the dialect design was based on local identity, combined with local architecture that had highly recognizable building elements (roof and ornament) promoted the spread of Islam in Indonesia.

In hot pursuit : fluctuating mating system and sexual selection in sand lizards

A changing climate is expected to have profound effects on many aspects of ectotherm biology. We report on a decade-long study of free-ranging sand lizards (Lacerta agilis), exposed to an increasing mean mating season temperature and with known operational sex ratios. We assessed year-to-year variation in sexual selection on body size and postcopulatory sperm competition and cryptic female choice. Higher temperature was not linked to strength of sexual selection on body mass, but operational sex ratio (more males) did increase the strength of sexual selection on body size. Elevated temperature increased mating rate and number of sires per clutch with positive effects on offspring fitness. In years when the “quality” of a female's partners was more variable (in standard errors of a male sexual ornament), clutches showed less multiple paternity. This agrees with prior laboratory trials in which females exercised stronger cryptic female choice when male quality varied more. An increased number of sires contributing to within-clutch paternity decreased the risk of having malformed offspring. Ultimately, such variation may contribute to highly dynamic and shifting selection mosaics in the wild, with potential implications for the evolutionary ecology of mating systems and population responses to rapidly changing environmental conditions.

Illusions vary because of the types of decorations at bowers, not male skill at arranging them, in great bowerbirds

Many animals use extended phenotypes to attract mates, but the availability of suitable resources in the environment can affect the size and form of these signals, with unknown consequences for honest signalling. In some populations of the great bowerbird, Ptilonorhynchus nuchalis, males arrange decorations by size, with smaller decorations placed closer to the bower entrance than larger decorations. This may create a more even background pattern from the female's viewpoint within the bower than if decorations were arranged randomly. Males show consistent, individual variation in the size-distance gradient, which could reflect variation among males in the cognitive skills needed to arrange decorations. We examined whether individual consistency in gradient characteristics is related to a male's skill at decoration arrangement or the types of decorations at bowers. We paired 18 males and switched bower decorations between pairs. We measured gradient characteristics before switching and 4 and 8 days after switching. Gradient characteristics after switching were related to those of the bower from which decorations were received, not to those of the male's own bower before switching. Gradient characteristics were also related to the types of decorations received, including bones and snail shells. These results suggest that variation among males in the size-distance gradient is explained by differences in the availability of decorations at bowers, not the cognitive skills required to arrange decorations. Although variation in gradient characteristics could indicate the male's ability to locate and transport particular decorations, it could also reflect local availability of objects, with no relationship to male quality.

Neohornibrookella sorrentae (Chapman and Crespin, 1928) and allied ostracod taxa from the Neogene of southeastern Australia: systematic and palaeoceanographical relationships, palaeoecology and palaeobiogeography

Three closely allied shallow marine taxa, Neohornibrookella sorrentae (Chapman and Crespin), Neohornibrookella glyphica (Neil), and Neohornibrookella nepeani sp. nov. are recorded from latest early Miocene to late Pliocene strata in southeastern Australia. These taxa, together with Neohornibrookella quadranodosa (Holden) from the Miocene of Midway Island (Northwestern Hawaiian Islands), form a morphologically distinct group of relatively large species (the sorrentae-group) within the genus Neohornibrookella Jellinek. Latitudinal expansion of the subtropical and warm-temperate climatic belts together with the influence of warm western boundary surface currents associated with the North and South Pacific gyres, are likely to have played key roles in the Miocene dispersal of this species group. Species of the sorrentae-group first migrated south from equatorial west Pacific regions into southeastern Australia during the early Miocene, under the influence of the East Australian Current. During three time intervals (i) latest early Miocene, (ii) latest late Miocene and (iii) earliest late Pliocene, forceful pulses of the East Australian Current played a significant role in propelling the widespread distribution of thermophilic Neohornibrookella species across southeast Australian shallow marine realms. During intervening middle and late Miocene times, Neohornibrookella species are only sporadically present across the Bass Strait region of southeast Australia, indicating a weaker East Australian Current influence and the cooling influence of coastal upwelling. During the mid early Pliocene Neohornibrookella species disappeared from the western Bass Strait region, suggesting the complete exclusion of East Australian Current waters from this region. This was probably due to the counteracting influence of the eastward flowing Zeehan Current (extension of the Leeuwin Current) impinging on the western Bass Strait region. This mid early Pliocene palaeobiogeographical partition in Bass Strait, defined by the distribution of sorrentae-group species, is here termed the Bassian Gateway. The two species, N. sorrentae and N. glyphica, occur concurrently during the mid Miocene in southeast Australia, but are associated with different lithofacies. It is hypothesised that there is a heterochronic evolutionary relationship expressed in the ornament of these two species. The thaerocytherid genera Neohornibrookella Jellinek, Tenedocythere Sissingh and Bosasella Bonaduce are here included in the new ostracod subfamily Tenedocytherinae.