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Urbanisation creates novel environments, not only through (abiotic) microhabitat alterations, but also due to changes in (biotic) inter- and intraspecific interactions. Where sheltering sites in urban habitats are limited, intra or interspecific interactions may increase, resulting in increased competition and changes in predation risk in urban areas compared to natural habitats. The Knysna Dwarf Chameleon (Bradypodion damaranum) occurs in both urban and natural settings, is extremely ornamented, and individuals have been observed with multiple wounds and scars. We therefore hypothesised that urban populations may have adapted to the physical features of urban habitats, and that this would be detectable through ornament size and bite force, as well as the presence of scarring. We quantified these traits from urban and natural populations from two separate localities (the towns of George and Knysna, South Africa). Our results showed that female and male B. damaranum from urban populations had a higher number of injuries and that urban males were more likely to be injured than males from natural habitats. Bite force was only recorded at one locality (Knysna), but both sexes in urban habitats had higher bite force when accounting for casque height as compared to those from the natural habitats. Urban chameleons also had less developed ornamentation but wider and/or higher heads compared to populations in natural habitats. Urban habitats had significantly lower tree density than natural habitats, and this may be a factor in driving the morphological differences between populations, whereby reduced ornamentation confers an advantage for remaining cryptic to predators in the open habitat but compromises the ability for signalling conspecifics with encounters escalating to physical contests. [ABSTRACT FROM AUTHOR]

The origin of the nodes on ostracod carapaces has been widely discussed in recent decades, and studies have shown that these characters can be produced as an individual response to changes in the environment which the specimens inhabit. Previous experiments with living ostracod species have shown that the variation in water salinity during the ecdysis phase, added to a deficiency in the regulation of internal osmotic pressure, may result in the formation of nodes on the new carapace. Based on this knowledge, a reassessment of fossil species may be necessary, especially in those in which the nodes were considered a diagnostic feature. The present work addresses a taxonomic review of the species Theriosynoecum pricei (Pinto and Sanguinetti, 1958), which is a marker for the Tithonian in the sedimentary basins of Northeast Brazil, adding an emendation to its description and bringing new information about the development of its nodes as ecophysiological and ecophenotypic response. Geochemical and lithological aspects are discussed, corroborating the palaeoenvironmental inferences presented here. [ABSTRACT FROM AUTHOR]

In birds, the process of speciation is closely associated with transitions in ornamentation, including coloration, plumage pattern, and song. To investigate the origins of these shifts and their connection to genetic changes, we conducted a study on one of the most highly ornamented songbirds, the Painted Bunting (Passerina ciris). The male Painted Buntings exhibits a stunning array of colors, with a red chest, blue head, green back, green coverts, and pink rump. In addition, Painted Buntings show a high level of genetic structure, with eastern and western populations that have fixed genetic differences in both nuclear and mitochondrial genes. Using non-invasive spectrophotometry techniques, we measured the coloration of six plumage patches on 88 museum specimens of male Painted Buntings in definitive plumage from across the range of the species. We predicted that there would be divergence between the genetically distinct eastern and western populations in ornamental coloration that is perceptible to a bunting but imperceptible to a human observer. However, we measured no consistent nor substantial difference in the plumage coloration of males from different populations. The observation of substantial divergence in nuclear and mitochondrial genotype with no change in ornamental coloration between populations of a brightly colored bird has important implications for the role of sexual selection in the process of speciation. [ABSTRACT FROM AUTHOR]

Scolecophidia (Squamata, Serpentes), commonly known as blindsnakes, wormsnakes or threadsnakes comprises a group of small snakes, with relatively few systematic and morphological studies when compared to Alethinophidia. Since the external morphology is very conserved amongst scolecophidians, internal morphological studies—such as the hemipenial morphology—are useful to unravel several systematic issues within the group. We aimed to describe the hemipenial morphology of Epictiavellardi (Epictinae, Leptotyphlopidae) based on 16 organs belonging to eight specimens. The organ is unilobed, with the body conspicuously narrower than the base and with the apex slightly expanded, without any macroscopic ornamentation. The comparison of the hemipenial morphology of E.vellardi with other hemipenes of Epictia spp. allowed us to identify two general morphological patterns for the genus, which are proposed and discussed in detail in the present study. The results found herein may be extremely relevant for future hemipenial descriptions. In addition, independent characters found in Types I and II (such as ornamentation, shape of base, body and apex) should be regarded for future systematic and evolutionary morphology studies within Leptotyphlopidae, in addition to assisting in the taxonomy and identification of species of the genus. [ABSTRACT FROM AUTHOR]

More than 4300 Eurasian elk (Alces alces) incisors, most of them pendants, were found in 84 burials in the Late Mesolithic cemetery of Yuzhniy Oleniy Ostrov, Northwest Russia. We analysed the manufacture techniques of elk teeth (4014), in the collection of the Peter the Great Museum of Anthropology and Ethnography, St Petersburg. A striking observation is that the manufacture of these pendants is similar in all burials. Teeth were worked by carving one or several grooves around the root tip. In addition to grooved ones, a number of teeth were not worked at all. The uniformity of the chosen species, tooth and techniques indicates that strict norms prevailed in the pendant industry. Despite the overall similarity, our study shows some variation in making pendants. A groove can cut the whole circumference of the root, or several distinct grooves can mark opposite sides of the root. Sometimes the grooves are deep and made carefully, and sometimes they are weak and made hastily. A typology of various groove types was created. In many graves, one groove type dominates. We interpret that this inter-burial variation and domination of one type resulted from personal choice and taste based on practicality. Such variation could also be associated with kin identifiers, but we did not find clear support for that in our study. Our study indicates that the groove types as such had no connection with particular ornaments, garments or hanging positions. [ABSTRACT FROM AUTHOR]

The organophosphatic-shelled brachiopod Discinisca sp. is first described from the Upper Jurassic of Northwestern Siberia. Its relief and microstructure of outer and inner sides of dorsal brephic and adult valves are described. Discinisca sp. differs from other Mesozoic discinids in the primary layer with concentric relief structures. [ABSTRACT FROM AUTHOR]

The organophosphate-shelled brachiopods are for the first time described from the Lower Devonian (Lochkovian) of the Timan–Pechora Basin. Several shells preserved both protegulum and brephic shell. The shell microstructure of the Early Devonian Orbiculoidea cf. magnifica Mergl, 2001, is described for the first time, including its changes at different developmental stages. [ABSTRACT FROM AUTHOR]

Hard animal materials were key components of prehistoric daily life, with many such raw materials shaped into diverse tool types and personal ornaments. With few exceptions, outside of the far south and north of Africa, osseous artefacts have been largely understudied on the continent, with this situation particularly applying to pastoralist contexts. Well-documented worked bone, ivory, or ostrich eggshell (OES) assemblages tend to be associated with hunter-gatherers and are generally interpreted with reference to contemporary hunter-gatherer toolkits. Study of osseous and OES technologies used by ancient or modern pastoralist populations, on the other hand, remains in its infancy. In this paper, we present an analysis of 14 worked bone, ivory, and OES artefacts from the Pastoral Neolithic site of Luxmanda located in north-central Tanzania. We apply technological trace analysis to understand histories of manufacture, use, and discard and compare our findings against the corpus of osseous and eggshell technologies recovered from terminal Pleistocene through Holocene sites of eastern Africa, providing a synthesis of this region for the first time. Finally, we explore the limited record for comparable technologies in recent pastoralist communities and argue that forager/food producer distinctions based on organic technologies are neither present nor meaningful based on current evidence. [ABSTRACT FROM AUTHOR]

In Hindustani classical music, notes and their different variations play an important role to arouse the aesthetic qualities of a rãga. Therefore, detection of notes is very much important to find out the different characteristics of a rãga, but the task is very much challenging due to presence of improvisations or ornamentations. In this work, melody contour is extracted from the music file using salience-based predominant melody extraction method. Initially, the notes were determined by optimizing the tolerance band and duration of notes. The output of initial note transcription system consists of notes, its duration, and their boundaries (onset and offset instants). For improving the accuracy of initial note transcription, the melody contour is divided into melodic segments, and categorized into four broad categories based on duration and transition characteristics of the initial transcribed notes. Different features and classification models have been explored for classifying the melodic segments into desired and undesired categories. Further, we further proposed two metrics to measure the performance of the proposed transcription system. [ABSTRACT FROM AUTHOR]

The shell microstructure of Late Jurassic rhynchonellids of the family Rhynchonellidae from the boreal basin of the Russian Platform is studied for the first time. The studied rhynchonellids differ in the shell microstructure from the Late Jurassic and Early Cretaceous rhynchonellids of the families Cyclothyrididae, Praecyclothyrididae, Basiliolidae, and Norellidae from the warm-water Mediterranean basin. The revealed peculiarities of shell structure of Rhynchonella loxiae (type species of Rhynchonella) may be added to the diagnosis of Rhynchonella and should be considered in characterizing the family Rhynchonellidae. [ABSTRACT FROM AUTHOR]

Some of the most spectacular visual signals found in the animal kingdom are based on dietarily derived carotenoid pigments (which cannot be produced de novo), with a general assumption that carotenoids are limited resources for wild organisms, causing trade-offs in allocation of carotenoids to different physiological functions and ornamentation. This resource trade-off view has been recently questioned, since the efficiency of carotenoid processing may relax the trade-off between allocation toward condition or ornamentation. This hypothesis has so far received little exploratory support, since studies of digestive efficiency of wild animals are limited due to methodological difficulties. Recently, a method for quantifying the percentage of fat in fecal samples to measure digestive efficiency has been developed in birds. Here, we use this method to test if the intensity of the carotenoid-based coloration predicts digestive efficiency in a wild bird, the house finch ( Haemorhous mexicanus). The redness of carotenoid feather coloration (hue) positively predicted digestion efficiency, with redder birds being more efficient at absorbing fats from seeds. We show for the first time in a wild species that digestive efficiency predicts ornamental coloration. Though not conclusive due to the correlative nature of our study, these results strongly suggest that fat extraction might be a crucial but overlooked process behind many ornamental traits. [ABSTRACT FROM AUTHOR]

Although the selective loss of individuals susceptible to disease can favor the evolution of female preference for older males, the interrelationship between age, infection, longevity, and mating success remains poorly characterized in natural populations. In a longitudinal study of 61 male common yellowthroats ( Geothlypis trichas), we found that the probability of infection with hematozoa increased as males aged from 1 to 5 years. Despite a significant, negative association between infection and longevity that partially masked age-effects, the odds that a male was infected with Trypanosoma, Plasmodium, or Leucocytozoon increased 71-212% per year. Nearly 75% of males in their first breeding season were either uninfected or infected with only a single parasite, while 50% of older males were infected with at least two parasites and 16% were infected with all three. No males escaped infection after their second breeding season. Older males were also more likely to sire extra-pair young (EPY) and, as a consequence, infection with multiple parasites was associated with a fourfold increase in the odds of producing EPY. Unlike younger males, 80% of the oldest males had a history of either surviving chronic infection or recovering. Combined with previous work showing higher diversity at the major histocompatibility complex among older males, our results suggest that the song and plumage traits that signal male age in common yellowthroats also, perforce, signal resistance to parasites. By preferring older males, females may obtain good genes for disease resistance even in the absence of any effect of infection on male ornamentation. [ABSTRACT FROM AUTHOR]

Female ornamentation evolves as a nonfunctional copy of functional male ornamentation or through direct selection on female ornamentation. Because females invest many resources in both reproduction and ornamentation, an evolutionary tradeoff between female ornamentation and maternal investment can be predicted, but it has rarely been demonstrated. Using phylogenetic comparative analysis, we studied egg size in relation to female fork depth in the family Hirundinidae, which has a wide range of fork depth (from 0 to >50 mm). Because deeply forked tails are aerodynamically costly, we predicted that species in which females have deeply forked tails suffer reduced egg size due to inefficient foraging during the egg formation period. Egg length was significantly related to nest type but not to female or male tail fork depth, whereas we found a significant negative relationship between egg breadth and female, but not male, tail fork depth. As a consequence, a significant negative relationship was found between egg volume and female, but not male, tail fork depth. Because female and male fork depths were not significantly related to clutch size, clutch size would not compensate the relationship between egg size and fork depth. The current finding supports the hypothesis that female ornamentation trades off with maternal investment. [ABSTRACT FROM AUTHOR]

This study describes and quantifies morphological valve traits of the ostracod Limnocythere rionegroensis from Patagonian steppe lakes and explores their association with lake water characteristics. Surface ornamentation was examined by scanning electron and transmitted light microscopy, and valve size and shape were analyzed using morphometric techniques. Limnocythere rionegroensis shows remarkable variations in surface ornamentation, based on which three morphotypes (MI, MII, and MIII) were identified. Valves of morphotypes MI and MIII are larger, show slight to moderate external reticulation, and a higher shape variability, whereas MII is characterized by a very conspicuous reticulation, lower shape variability, and smaller valves. Outline analysis yielded a great shape disparity related to the dorsal margin slope. MI was found in sexual populations from euhaline to mesohaline ephemeral lake; MII occurs in parthenogenetic populations from mesohaline to oligohaline permanent or ephemeral lakes; and MIII, from both sexual and asexual populations, inhabits a broad range of environmental conditions in terms of salinity and stability. Limnocythere rionegroensis intraspecific variations may be caused by environmental parameters and genetic factors associated to reproductive strategies. These results contribute to the knowledge of extant L. rionegroensis morphological variability and provide additional clues to improve the environmental interpretation of fossil assemblages. [ABSTRACT FROM AUTHOR]

Guest editor Reza Sarhangi introduces the papers in NNJ issue 18(1) dedicated to Persian architecture and mathematics. [ABSTRACT FROM AUTHOR]

Adaptive phenotypic divergence can arise when environments vary in ways favoring alternative phenotypic optima. In aquatic habitats, the costs of locomotion are expected to increase with water velocity, generally favoring a more streamlined body and the reduction of traits that produce drag. However, because streamlining in fish may come at the cost of maneuverability, the net benefits of drag reduction can differ not only among habitats, but also among individuals (or classes of individuals) that rely on locomotion for different uses (e.g., males vs. females or adults vs. juveniles). We tested these predictions by exploring relationships among river velocity, body streamlining, ornamental fin size, and male reproductive condition in the steelcolor shiner ( Cyprinella whipplei), a small-bodied North American cyprinid. Overall, males in peak reproductive condition (defined by the development of sexually dimorphic tubercles) had less streamlined bodies and larger ornamental fins than males in lower reproductive condition or individuals lacking these secondary sexual characters (females and immature males). There was a relationship between river velocity and body streamlining only for males in peak reproductive condition, but it was in the opposite direction of our predictions: these males were less streamlined in faster rivers. We found only weak support for the prediction that ornamental fin size would be negatively associated with river velocity. Overall, these results suggest either that drag is not an important selective pressure in these habitats, or that the sexual selection advantages of a deep body and large fin compensate any natural selection costs for C. whipplei males. This study highlights the often overlooked diversity of selective pressures acting on streamlining in fishes, and can offer novel insights and predictions allowing a more nuanced understanding of fish ecomorphology. [ABSTRACT FROM AUTHOR]

The carotenoid-based ornaments displayed by many birds often play key roles in social and sexual signalling, revealing information about individual quality. However, the proximate regulation of the honesty of sexual traits remains controversial. Understanding the mechanisms of coloured trait production and maintenance requires an accurate description of their chemical composition and of the physiological pathways involved in pigment production and deposition in the ornaments. Carotenoid-based colouration has been extensively studied in birds, but such information is often lacking for coloured integuments other than feathers, such as fleshy carotenoid-based ornaments. Here we report the carotenoid composition of the combs of the red grouse ( Lagopus lagopus scoticus), a sexual trait that honestly reveals individual quality. In the present study, we also investigated blood carotenoid content, as well as associations between carotenoids, retinol and tocopherol (the active forms of vitamin A and E, respectively) within the ornament. We found that comb pigmentation was primarily the result of two red ketocarotenoids (astaxanthin and papilioerythrinone), which are synthesised from their dietary precursors (zeaxanthin and lutein) directly at the comb integument. These red ketocarotenoids are largely deposited esterified with fatty acids. Astaxanthin concentration in the comb was found to negatively correlate with retinol levels but positively correlate with tocopherol levels. Considering evidence from this and other studied species, we suggest that carotenoid esterification is a characteristic of coloured fleshy integuments, probably affecting pigment stability and colouration in living tissues, with subsequent effects on their signalling role and maintenance costs. We found little evidence that the honesty of this signal would result from a direct connection with vitamin A metabolism, as recently proposed. Rather, honest signalling via comb colouration appears more related to potential allocation trade-offs of some specific dietary precursors or to the capacity of individuals to manage the redox reactions interfering with carotenoid metabolism. [ABSTRACT FROM AUTHOR]

Sexual selection determines the elaboration of morphological and behavioural traits and thus drives the evolution of phenotypes. Sexual selection on males and females can differ between populations, especially when populations exhibit different breeding systems. A substantial body of literature describes how breeding systems shape ornamentation across species, with a strong emphasis on male ornamentation and female preference. However, whether breeding system predicts ornamentation within species and whether similar mechanisms as in males also shape the phenotype of females remains unclear. Here, we investigate how different breeding systems are associated with male and female ornamentation in five geographically distinct populations of Kentish plovers Charadrius alexandrinus. We predicted that polygamous populations would exhibit more elaborate ornaments and stronger sexual dimorphism than monogamous populations. By estimating the size and intensity of male ( n = 162) and female ( n = 174) melanin-based plumage ornaments, i.e. breast bands and ear coverts, we show that plumage ornamentation is predicted by breeding system in both sexes. A difference in especially male ornamentation between polygamous (darker and smaller ornaments) and monogamous (lighter and larger) populations causes the greatest sexual dimorphism to be associated with polygamy. The non-social environment, however, may also influence the degree of ornamentation, for instance through availability of food. We found that, in addition to breeding system, a key environmental parameter, rainfall, predicted a seasonal change of ornamentation in a sex-specific manner. Our results emphasise that to understand the phenotype of animals, it is important to consider both natural and sexual selection acting on both males and females. [ABSTRACT FROM AUTHOR]

Archaeology and mathematics work together to reconstruct the form and dimensions of a vault originally adorned with a set of twenty-five stucco coffers in the shape of concave octagons, today conserved in the Archaeological Museum in Naples. Measurements were taken to determine the curvature and orientation of the coffers. Two methods used to establish the size of the vault permitted an approximation of the vault width, making it possible to propose limited possibilities for the number of coffers transversally to the vault, and how they were displayed on it. Further studies were made of the decorative scheme in order to suggest a plausible construction process for the coffers with tools and techniques usual at the time, using only arcs of circles. For this, the front side of the coffers was considered to be plane, which led us to establish that they were included in an all-over scheme of squares and that the concentric octagonal frames were very likely drawn from two families of circles. Then differential calculus showed us that the differences due to the plane approximation of the cylindrical shape of the vault were negligible with regard to the precision of the guidelines drawn in situ. Finally we suggest a complete decorative scheme, using various clues such as subject, orientation, curvature and colours of the tesserae decorating the framing. [ABSTRACT FROM AUTHOR]

In the Renaissance, geometric perspectives became a method of architectural reasoning. We look at two works: a painting attributed to Pedro Berruguete and an engraving by Juan Bautista Villalpando in order to to discover the complex relationship between geometry and architecture, and in particular, the form of representation. Our analysis is based on the idea that geometric perspective meant architecture of the period was capable of graphically controlling reality through a high degree of geometric precision. [ABSTRACT FROM AUTHOR]

For a variety of technical and conceptual reasons, biologists have come to use several different methods to quantify the colors of animals. However, the relative abilities of these different color-scoring procedures to capture variation in the actual color-generating mechanisms-pigment or structural composition of the integument-have never been tested systematically. Here, we examined which commonly employed color metrics predict carotenoid content of ornaments in three avian species (house finch Carpodacus mexicanus, mallard duck Anas platyrhynchos, and zebra finch Taeniopygia guttata). We used spectrophotometry to measure reflectance spectra from beak and feather tissue, calculated numerous color metrics (e.g., hue, chroma, brightness, principal components, and tetrahedral color space position) from these spectra, and determined carotenoid content at the site of color measurement with high-performance liquid chromatography. We found that several principal component, tristimulus, and avian visual model metrics significantly correlated with carotenoid content of house finch feathers and duck beaks. Carotenoid content of mallard beaks was most closely correlated with brightness and saturation metrics, whereas in house finch feathers, carotenoid concentration was best captured by hue and saturation metrics. According to tristimulus scores and visual models, we found that the ultraviolet portion of the spectrum was not an essential predictor of variation in carotenoid content. Also, visual model chromatic contrasts generally were not significant predictors of carotenoid content, although some achromatic contrasts and tetrahedral color space vector parameters were. Our results indicate that numerous methods, especially tristimulus scores, are suitable for capturing pigment-based color variation in two carotenoid-containing ornaments, and we discuss the merits and shortcomings of these different approaches. In contrast, there were no significant relationships between any color metrics and the carotenoid content of zebra finch beaks, suggesting that other color-generating mechanisms besides carotenoids may contribute to color variability in this species. [ABSTRACT FROM AUTHOR]

The evolutionary patterns of Productida (brachiopod) morphology throughout the Permian show that while the percentage proportion of Productida (brachiopod) with strongly concentric and radial ornamentation declined from the Cisuralian to the Guadalupian, and then increased towards the Changhsingian via Wuchiapingian, the percentage proportion of Productida (brachiopod) with fine concentric and radial ornamentation distinctly increased from the Cisuralian to the Guadalupian, slightly declined towards the Wuchiapingian, and then increased towards the Changhsingian. From the Cisuralian to the Changhsingian, the percentage proportion of brachiopods with spinose ornamentation shows a persistent declining trend. The shell size generally indicates a miniaturization trend at species level during the Wuchiapingian to Changhsingian (including the transitional bed). These evolutionary patterns of brachiopod ornamentation and size are possibly related to the anoxia, food shortage, sea-level fluctuation, and change of substrate in the Permian (including the Permian-Triassic transitional interval) in South China. [ABSTRACT FROM AUTHOR]

Melanin-based ornaments are often involved in signaling aggression and dominance, and their role in sexual selection is increasingly recognized. We investigated the functions of a melanin-based plumage ornament (facial ‘mask’) in male Eurasian penduline tits Remiz pendulinus in the contexts of male–male aggression, mating success, and parental care. The penduline tit is a passerine bird with a unique mating system in which both sexes may mate with several mates in a breeding season, and one (or both) parent deserts the clutch. Our study revealed that mask size of males is more likely an honest signal used by females in their mate choice decisions than a trait involved in male–male competition. First, mask size increased with both age and body condition, indicating that the mask may signal male quality. Second, males with larger masks paired more quickly and had more mates over the breeding season than males with smaller masks. Third, we found no evidence that male mask size signals male–male aggression or dominance during competitive encounters. The increased mating success of large-masked males, however, did not translate into higher reproductive success, as nestling survival decreased with mask size. Therefore, we conclude that there is either no directional selection on male mask size or males with larger masks receive indirect, long-term benefits. [ABSTRACT FROM AUTHOR]

Studies of the relationship between sexual traits and immune function have been at the forefront of sexual selection during the last decade. Whereas evidence is accumulating that there is a trade-off between sexual ornamentation and immunocompetence, the reasons for this trade-off are still unknown. Importantly, most studies have addressed this issue only at the adult stage, when sexual ornamentation and immune function may be fully developed. We show here that juvenile cell-mediated immune response is negatively correlated with subsequent size of an adult sexual ornament in the Chinese quail, Coturnix chinensis. This suggests that the cost of development of a functional immune system is traded off against secondary sexual traits, and that costs of high immunocompetence in juveniles may not be manifested until sexual maturity. Ontogenetic studies of the development of the immune function and associated costs and trade-offs are likely to provide a more complete picture of the links between sexual selection and immunobiology. [ABSTRACT FROM AUTHOR]

The coelomycete Dwiroopa was determined to be the correct genus for Harknessia lythri, and a new combination is made for this species. The type species of Dwiroopa, D. ramya, is redescribed and illustrated based on the type specimen for which a lectotype is designated. A key to the two species of Dwiroopa is presented along with a discussion of their similarities and differences. The genus Dwiroopa is distinguished from Harknessia by conidial characteristics. In Dwiroopa the macroconidia have widely spaced, longitudinal slits around the conidia and lack a basal appendage, whereas in Harknessia the macroconidia are smooth or have closely spaced, longitudinal slits on only one side of the conidia and often have a true basal appendage. Both Dwiroopa and Harknessia are included in the Diaporthales. [ABSTRACT FROM AUTHOR]

Qualities of the stratified pollen walls were evaluated for their possible role in pollination (pollination modes, and pollen tube formation). The importance of studying pollen grains in their respective natural state is noted. Examples of pollen morphological features specific to pollination vectors are rare and difficult to demonstrate. However, some complex, but significant correlations are reported. [ABSTRACT FROM AUTHOR]

This study used both correlative and experimental video playback methods to test the hypothesis that the secondary sexual traits of male wolf spiders act to increase the efficacy of visual courtship displays. Direct observations of courtship of several lycosid genera and a review of the literature revealed a significant association between ornamentation and visual courtship displays. This suggests that the ornamentation may be playing the role of amplifier for a visual display. To test this hypothesis, male courtship behaviors of four Schizocosa species were experimentally manipulated using video-imaging techniques. Females of species with non-visually displaying, non-ornamented males ( Schizocosa duplex and S. uetzi) did not increase in frequency of receptivity when tufts were added to conspecific males. In a species with a visual display and foreleg pigmentation ( S. stridulans), the addition of foreleg tufts increased female receptivity. In a tufted species ( S. crassipes), females tended to decrease their receptivity when male ornamentation was completely removed. In visually displaying species, ornamentation acts to increase female receptivity, supporting its role as an amplifier of a visual display. [ABSTRACT FROM AUTHOR]

A detailed study of surface ornamentation under light and scanning electron microscope is undertaken. The present observations have added further to the knowledge in taxonomic identification of Cosmarium botrytis Menegh, in particular because the species revealed a variety of surface ornamentation based on which various species of Cosmarium are specifically identified. [ABSTRACT FROM AUTHOR]