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Colour Morphs (colour + morph)
Selected AbstractsCorrelated morphological and colour differences among females of the damselfly Ischnura elegansECOLOGICAL ENTOMOLOGY, Issue 3 2009JESSICA K. ABBOTT Abstract 1.,The female-limited colour polymorphic damselfly Ischnura elegans has proven to be an interesting study organism both as an example of female sexual polymorphism, and in the context of the evolution of colour polymorphism, as a model of speciation processes. 2.,Previous research suggests the existence of correlations between colour morph and other phenotypic traits, and the different female morphs in I. elegans may be pursuing alternative phenotypically integrated strategies. However, previous research on morphological differences in southern Swedish individuals of this species was only carried out on laboratory-raised offspring from a single population, leaving open the question of how widespread such differences are. 3.,The present study therefore analysed multi-generational data from 12 populations, investigating morphological differences between the female morphs in the field, differences in the pattern of phenotypic integration between morphs, and quantified selection on morphological traits. 4.,It was found that consistent morphological differences indeed existed between the morphs across populations, confirming that the previously observed differences were not simply a laboratory artefact. It was also found, somewhat surprisingly, that despite the existence of sexual dimorphism in body size and shape, patterns of phenotypic integration differed most between the morphs and not between the sexes. Finally, linear selection gradients showed that female morphology affected fecundity differently between the morphs. 5.,We discuss the relevance of these results to the male mimicry hypothesis and to the existence of potential ecological differences between the morphs. [source] Short-term assessment of dung beetle response to carbosulfan treatment against desert locust in SudanJOURNAL OF APPLIED ENTOMOLOGY, Issue 8 2009H. Eriksson Abstract The beneficial role of dung beetles (Coleoptera: Scarabaeidae) is well known. Potential risks to these beetles from the widespread use of insecticides against the desert locust, a significant plant pest in Africa, the Near East and South West Asia, have not been studied previously. Short-term responses of dung beetles to carbamate carbosulfan (Marshal®, ultra low-volume formulation, 100 g active ingredient ha,1) were assessed during desert locust control operations at five sites within two major biotopes: Acacia tortilis shrubland and cultivated wetland; on the Red Sea Coast of Sudan. The study took place during January,February 2004. At each site, fresh dung from Zebu cows was placed in areas targeted for desert locust control. Dung pats were placed in plots in two areas and left for 24 h, before and after insecticide application. Beetles were extracted by floatation. There was a significant decrease in abundance between the pre- and post-spray period in treated areas for the Scarabaeinae species Onthophagus margaritifer (a dark colour morph). In contrast, it was found that Aphodius lucidus and beetles at the subfamily level of Aphodiinae increased in numbers after insecticide treatment. Mortality and sublethal impacts as well as a repellent effect of the insecticide may explain the decrease in Onthophagus margaritifer, while the increase in Aphodiinae beetles could be an indirect response to lower numbers of Scarabaeinae beetles in competing for the same resource. These organisms and the applied methodology may be useful for environmental monitoring of desert locust control, thus further studies are suggested. The assessment also revealed a marked difference between the two biotopes with high abundance and species richness of dung beetles in A. tortilis shrubland, while these measures were low in the cultivated wetland. Five new species of dung beetles for Sudan were found in this study. [source] Dietary conservatism may facilitate the initial evolution of aposematismOIKOS, Issue 3 2003R. J. Thomas It has generally been assumed that warningly coloured organisms pay a cost associated with their increased visibility, because naïve predators notice and eat them. This cost is offset by their enhanced protection from educated predators who associate the colour pattern with unprofitability. However, some studies have suggested that avoidance of novel prey by avian predators ("dietary conservatism") can actually place novel colour morphs at a selective advantage over familiar ones, even when they are highly conspicuous. To test this idea, we experimentally simulated the appearance of a single novel-coloured mutant in small populations (20 individuals) of palatable artificial prey. The colour morph frequencies in each "generation" were determined by the relative survival of the previous generation under predation by birds. We used wild-caught European robins Erithacus rubecula foraging on pastry "prey" of different colours. The aim was to test whether prey selection by predators prevented or facilitated the novel colour morph persisting in the prey population over successive generations. We found that the novel colour morph quickly increased to fixation in 14/40 prey "populations", and at least once each in 8 of the 10 birds tested. Novel mutants of the classic aposematic colours (red and yellow) reached fixation most frequently, but even the green and blue novel morphs both increased to fixation in 2/40 trials. Novel colours reached fixation significantly faster than could be accounted for by drift, indicating active avoidance by the birds. These results suggest that a novel colour morph arising in a prey population can persist and increase under the selective pressure imposed by predators, even to the local exclusion of the original morph, despite being fully palatable. The consequences of this finding are discussed in relation to receiver psychology, the evolution of aposematism and the existence of polymorphism in Müllerian mimics. [source] Complex trait differentiation between host-populations of the pea aphid Acyrthosiphon pisum (Harris): implications for the evolution of ecological specialisationBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009ADRIEN FRANTZ Variation in traits affecting preference for, and performance on, new habitats is a key factor in the initiation of ecological specialisation and adaptive speciation. However, habitat and resource use also involves other traits whose influence on ecological and genetic divergence remains poorly understood. In the present study, we investigated the extent of variation of life-history traits among sympatric populations of the pea aphid Acyrthosiphon pisum, which shows several host races that are specialised on various plants of the family Fabaceae plants and is an established model for ecological speciation. First, we assessed the community structure of microbial partners within host populations of the pea aphid. The effect of these microbes on host fitness is uncertain, although there is growing evidence that they may modulate various important adaptive traits of their host such as plant utilisation and resistance against natural enemies. Second, we performed a multivariate analysis on several ecologically relevant features of host populations recorded in the present and previous studies (including microbial composition, colour morph, reproductive mode, and male dispersal phenotype), enabling the identification of correlations between phenotypic traits. We discuss the ecological significance of these associations of traits in relation to the habitat characteristics of pea aphid populations, and their consequences for the evolution of ecological specialisation and sympatric speciation. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 718,727. [source] Sexual dichromatism and male colour morph in ultraviolet-B reflectance in two populations of the jumping spider Phintella vittata (Araneae: Salticidae) from tropical ChinaBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2008JINGJING LI In the literature on animal use of ultraviolet (UV) vision and UV reflectance, it has usually been UV-A (315,400 nm) that is considered. Animals are generally assumed to be unable to discriminate UV-B (280,315 nm) from other wavelengths in natural sunlight. Recently, some animals are known to be able to detect and respond directly to UV-B in order to avoiding exposure to it. However, there is no evidence that the hue corresponding to UV-B is salient to an animal during intraspecies communication. Using Phintella vittata, an ornate jumping spider from two geographically different populations in China, we investigated geographical, intersexual, intrasexual, and interpopulation variation in UV reflectance. We found that both the males and the females of P. vittata reflect UV light, and that the reflection bands are located in UV-B, a part of reflectance spectrum never previously investigated. We also found a great deal of population variation in the UV-B spectral reflectance. Furthermore, two colour morphs, the ,green' and ,yellow' morphs, are identified for adult males for both populations, and both morphs differ greatly in both UV-B and human-visible wavelengths. This is the first demonstration of a UV-B reflecting salticid and UV-B sexual dichromatism. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 7,20. [source] Behavioural evidence for ultraviolet vision in a tetraonid species , foraging experiment with black grouse Tetrao tetrixJOURNAL OF AVIAN BIOLOGY, Issue 2 2002Heli Siitari In addition to wavelengths visible to humans (400,700 nm), many birds are able to detect near ultraviolet light (320,400 nm). Most studies of ultraviolet (UV) vision in birds have concentrated on the importance of UV vision in intraspecific signalling, especially in passerine birds. However, birds may also use UV vision for other purposes, e.g. foraging. We performed a laboratory experiment to test whether a tetraonid species, black grouse Tetrao tetrix, could detect the difference between UV-reflecting and non-UV-reflecting food items (two colour morphs of bilberry Vaccinium myrtillus). Black grouse preferred UV-reflecting berries when UV light was used for illumination, but showed no preference in the absence of UV light. This observation establishes a potential UV sensitivity in this species; such a sensitivity should be considered in behavioural experiments with this species. [source] Evidence for selection on coloration in a Panamanian poison frog: a coalescent-based approachJOURNAL OF BIOGEOGRAPHY, Issue 5 2010Jason L. Brown Abstract Aim, The strawberry poison frog, Oophaga pumilio, has undergone a remarkable radiation of colour morphs in the Bocas del Toro archipelago in Panama. This species shows extreme variation in colour and pattern between populations that have been geographically isolated for < 10,000 years. While previous research has suggested the involvement of divergent selection, to date no quantitative test has examined this hypothesis. Location, Bocas del Toro archipelago, Panama. Methods, We use a combination of population genetics, phylogeography and phenotypic analyses to test for divergent selection in coloration in O. pumilio. Tissue samples of 88 individuals from 15 distinct populations were collected. Using these data, we developed a gene tree using the mitochondrial DNA (mtDNA) d-loop region. Using parameters derived from our mtDNA phylogeny, we predicted the coalescence of a hypothetical nuclear gene underlying coloration. We collected spectral reflectance and body size measurements on 94 individuals from four of the populations and performed a quantitative analysis of phenotypic divergence. Results, The mtDNA d-loop tree revealed considerable polyphyly across populations. Coalescent reconstructions of gene trees within population trees revealed incomplete genotypic sorting among populations. The quantitative analysis of phenotypic divergence revealed complete lineage sorting by colour, but not by body size: populations showed non-overlapping variation in spectral reflectance measures of body coloration, while variation in body size did not separate populations. Simulations of the coalescent using parameter values derived from our empirical analyses demonstrated that the level of sorting among populations seen in colour cannot reasonably be attributed to drift. Main conclusions, These results imply that divergence in colour, but not body size, is occurring at a faster rate than expected under neutral processes. Our study provides the first quantitative support for the claim that strong diversifying selection underlies colour variation in the strawberry poison frog. [source] Multivariate phenotypes and the potential for alternative phenotypic optima in wall lizard (Podarcis muralis) ventral colour morphsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2010B. CALSBEEK Abstract A major goal in evolutionary biology is to determine how phenotypic variation arises and is maintained in natural populations. Recent studies examining the morphological, physiological and behavioural differences among discrete colour morphotypes (morphs) have revealed several mechanisms that maintain discrete variation within populations, including frequency-dependence, density-dependence and correlational selection. For example, trade-offs over resource allocation to morphological, physiological and behavioural traits can drive correlational selection for morph-specific phenotypic optima. Here, we describe a ventral colour polymorphism in the wall lizard (Podarcis muralis) and test the hypothesis that morphs differ along multivariate axes defined by trade-offs in morphological, physiological, and immunological traits. We show that ventral colour is a discrete trait and that morphs differ in body size, prevalence of infection by parasites and infection intensity. We also find that morphs differ along multivariate phenotypic axes and experience different multivariate selection pressures. Our results suggest that multivariate selection pressures may favour alternative optimal morph-specific phenotypes in P. muralis. [source] Phenotypic and genetic variation in emergence and development time of a trimorphic damselflyJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2005J. ABBOTT Abstract Although colour polymorphisms in adult organisms of many taxa are often adaptive in the context of sexual selection or predation, genetic correlations between colour and other phenotypic traits expressed early in ontogeny could also play an important role in polymorphic systems. We studied phenotypic and genetic variation in development time among female colour morphs in the polymorphic damselfly Ischnura elegans in the field and by raising larvae in a common laboratory environment. In the field, the three different female morphs emerged at different times. Among laboratory-raised families, we found evidence of a significant correlation between maternal morph and larval development time in both sexes. This suggests that the phenotypic correlation between morph and emergence time in the field has a parallel in a genetic correlation between maternal colour and offspring development time. Maternal colour morph frequencies could thus potentially change as correlated responses to selection on larval emergence dates. The similar genetic correlation in male offspring suggests that sex-limitation in this system is incomplete, which may lead to an ontogenetic sexual conflict between selection for early male emergence (protandry) and emergence times associated with maternal morph. [source] Predation and the persistence of melanic male mosquitofish (Gambusia holbrooki)JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2004L. Horth Abstract The empirical reasons for the persistent rarity of a genotype are typically complex and tedious to identify, particularly in nature. Yet rare morphs occur in a substantial fraction of phenotypic polymorphisms. A colour polymorphism has persisted for decades in the eastern mosquitofish, yet why this is so remains obscure. Here, I report the results of (1) intensive sampling at 45 natural sites to obtain the frequency distribution of the melanic (black) mosquitofish morph in Florida, (2) predation trials, conducted independently in mesocosms, with three different predatory species and (3) two mark-recapture studies, conducted in nature. This work (1) documents the rarity of melanic mosquitofish in nature, (2) demonstrates that melanic males experience a selective advantage over silver males in the presence of predators, (3) indicates no difference in the colour morphs, survival at a natural site essentially devoid of these predators, although suggesting a higher rate of recapture for melanic males at a site rife with predators. Overall, selective predation appears to contribute to the persistence of the melanic morph, despite its rarity in nature. [source] Phylogeography and speciation of colour morphs in the colonial ascidian Pseudodistoma crucigasterMOLECULAR ECOLOGY, Issue 10 2004I. TARJUELO Abstract Variation in pigmentation is common in marine invertebrates, although few studies have shown the existence of genetic differentiation of chromatic forms in these organisms. We studied the genetic structure of a colonial ascidian with populations of different colour morphs in the northwestern Mediterranean. A fragment of the c oxidase subunit 1 (COI) mitochondrial gene was sequenced in seven populations of Pseudodistoma crucigaster belonging to three different colour morphs (orange, yellow and grey). Maximum likelihood analyses showed two well-supported clades separating the orange morph from the yellow-grey morphotypes. Genetic divergence between these clades was 2.12%, and ,ST values between populations of the two clades were high (average 0.936), pointing to genetic isolation. Nested clade and coalescence analyses suggest that a past fragmentation event may explain the phylogeographical origin of these two clades. Non-neutral mtDNA evolution is observed in our data when comparing the two clades, showing a significant excess of nonsynonymous polymorphism within the yellow,grey morphotype using the McDonald,Kreitman test, which is interpreted as further support of reproductive isolation. We conclude that the two clades might represent separate species. We compare the population genetic differentiation found with that estimated for other colonial and solitary ascidian species, and relate it to larval dispersal capabilities and other life-history traits. [source] Lack of mitochondrial genetic structure in hamlets (Hypoplectrus spp.): recent speciation or ongoing hybridization?MOLECULAR ECOLOGY, Issue 11 2003Marina L. Ramon Abstract Species in the genus Hypoplectrus (hamlet fish) have been recognized primarily on the basis of colour morphology, which varies substantially. Limited differentiation in other morphological characters, however, has led to ongoing debate about their taxonomy. Our analysis of mtDNA sequences demonstrates neither reciprocal monophyly nor significant genetic differentiation among hamlet colour morphs. These data are potentially consistent with a model of recent speciation due to sexual selection on colour morphology. The presence within hamlets of two divergent mtDNA clades, however, suggests a longer history during which hybridization and gene flow have prevented the differentiation of hamlet colour morphs, at least in neutral genetic markers. [source] Characterization of 12 microsatellite markers in Serranus cabrilla (Pisces: Serranidae)MOLECULAR ECOLOGY RESOURCES, Issue 1 2006J. CARRERAS-CARBONELL Abstract The commercial comber Serranus cabrilla is widely distributed in the Atlanto-Mediterranean region, inhabiting a great variety of habitats and depths. We developed primers for 12 polymorphic microsatellite loci to analyse the genetic structure between comber populations and between their colour morphs in order to establish correct fisheries management. Characterization of 25 individuals from Columbretes Islands (Spain) showed an average large number of alleles (9.5 ± 1.3) and observed heterozygosity (0.657 ± 0.06). Only two loci showed significant departure from Hardy,Weinberg equilibrium. We found no evidence of linkage disequilibrium between pairs of loci. We rejected for primer design one clone with a microsatellite within the transposable element TX_FR2. [source] Dietary conservatism may facilitate the initial evolution of aposematismOIKOS, Issue 3 2003R. J. Thomas It has generally been assumed that warningly coloured organisms pay a cost associated with their increased visibility, because naïve predators notice and eat them. This cost is offset by their enhanced protection from educated predators who associate the colour pattern with unprofitability. However, some studies have suggested that avoidance of novel prey by avian predators ("dietary conservatism") can actually place novel colour morphs at a selective advantage over familiar ones, even when they are highly conspicuous. To test this idea, we experimentally simulated the appearance of a single novel-coloured mutant in small populations (20 individuals) of palatable artificial prey. The colour morph frequencies in each "generation" were determined by the relative survival of the previous generation under predation by birds. We used wild-caught European robins Erithacus rubecula foraging on pastry "prey" of different colours. The aim was to test whether prey selection by predators prevented or facilitated the novel colour morph persisting in the prey population over successive generations. We found that the novel colour morph quickly increased to fixation in 14/40 prey "populations", and at least once each in 8 of the 10 birds tested. Novel mutants of the classic aposematic colours (red and yellow) reached fixation most frequently, but even the green and blue novel morphs both increased to fixation in 2/40 trials. Novel colours reached fixation significantly faster than could be accounted for by drift, indicating active avoidance by the birds. These results suggest that a novel colour morph arising in a prey population can persist and increase under the selective pressure imposed by predators, even to the local exclusion of the original morph, despite being fully palatable. The consequences of this finding are discussed in relation to receiver psychology, the evolution of aposematism and the existence of polymorphism in Müllerian mimics. [source] Photoperiodic and temperature control of diapause induction and colour change in the southern green stink bug Nezara viridulaPHYSIOLOGICAL ENTOMOLOGY, Issue 2 2003Dmitry L. Musolin Abstract. The effect of photoperiod and temperature on the duration of the nymphal period, diapause induction and colour change in adults of Nezara viridula (L.) (Heteroptera: Pentatomidae) from Japan was studied in the laboratory. At 20 °C, the developmental period for nymphs was significantly shorter under LD 10 : 14 h (short day) and LD 16 : 8 h (long day) than under intermediate photoperiods, whereas at 25 °C it was slightly shorter under intermediate than short- and long-day conditions. It is assumed that photoperiod-mediated acceleration of nymphal growth takes place in autumn when day-length is short and it is unlikely that nymphal development is affected by day-length under summer long-day and hot conditions. Nezara viridula has an adult diapause controlled by a long-day photoperiodic response. At 20 °C and 25 °C in both sexes, photoperiodic responses were similar and had thresholds close to 12.5 h, thus suggesting that the response is thermostable within this range of temperatures and day-length plays a leading role in diapause induction. Precopulation and preoviposition periods were significantly longer under near-critical regimes than under long-day ones. Short-day and near-critical photoperiods induced a gradual change of adult colour from green to brown/russet. The rate of colour change was significantly higher under LD 10 : 14 h than under LD 13 : 11 h, suggesting that the colour change is strongly associated with diapause induction. The incidences of diapause or dark colour did not vary among genetically determined colour morphs, indicating that these morphs have a similar tendency to enter diapause and change colour in response to short-day conditions. [source] Orange, yellow and white-cream: inheritance of carotenoid-based colour in sunflower pollenPLANT BIOLOGY, Issue 1 2010M. Fambrini Abstract Inheritance of pollen colour was studied in sunflower (Helianthus annuus L.) using three distinct pollen colour morphs: orange, yellow and white-cream. Orange is the most common colour of sunflower pollen, while the yellow morph is less frequent. These two types were observed in the inbred lines F11 and EF2L, respectively. White-cream pollen is a rare phenotype in nature, and was identified in a mutant, named white-cream pollen, recovered in the R2 generation of an in vitro regenerated plant. The F11 inbred line was used as starting material for in vitro regeneration. The carotenoid content of these three pollen morphs differed, and was extremely reduced in white-cream pollen. The phenotype of F1 populations obtained by reciprocal crosses revealed that the orange trait was dominant over both white-cream and yellow. Segregation of F2 populations of both crosses, orange × yellow and orange × white-cream, approached a 3:1 ratio, indicating the possibility of simple genetic control. By contrast, a complementation cross between the two lines with white-cream and yellow pollen produced F1 plants with orange pollen. The F2 populations of this cross-segregated as nine orange: four white-cream: four yellow. A model conforming to the involvement of two unlinked genes, here designated Y and O, can explain these results. Accessions with yellow pollen would have the genotype YYoo, the white-cream pollen mutant would have yyOO and the accession with orange pollen would have YYOO. Within F2 populations of the cross white-cream × yellow a new genotype, yyoo, with white-cream pollen was scored. The results of the cross yyoo × YYoo produced only F1 plants with yellow pollen, supporting a recessive epistatic model of inheritance between two loci. In this model, yy is epistatic on O and o. In F2 populations, the distributions of phenotypic classes suggested that the genetic control of carotenoid content is governed by major genes, with large effects segregating in a background of polygenic variation. These three pollen morphs can provide insight into the sequence in which genes act, as well into the biochemical pathway controlling carotenoid biosynthesis in anthers and the transfer of these different pigments into pollenkitt. [source] Origin of the disjunct distribution of flower colour polymorphism within Limonium wrightii (Plumbaginaceae) in the Ryukyu ArchipelagoBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009SHUN'ICHI MATSUMURA The sea lavender, Limonium wrightii, has six morphs of flower colour variation. The geographical distribution of flower colour morphs is disjunct; the distribution of the pink flower morph is divided into two subregions, and that of the yellow flower morph intervenes between them. The present study aimed to examine the origin of this apparent distribution pattern of flower colour in L. wrightii. Two main hypotheses (i.e. past dispersal events and phenotypic changes by natural selection and/or stochastic processes) have been proposed to account for the origin of leapfrog distribution patterns. To determine which hypothesis was applicable, we conducted a molecular phylogenetic analysis using sequence variation in chloroplast DNA (three regions of intergenic spacers, trnG - trnfM, trnV - trnM, and psbA-trnH). We sequenced 58 accessions of L. wrightii frin 28 islands in the Ryukyu Archipelago and the Izu-Ogasawara Islands, located south of the Japanese mainland, and 12 accessions of four congeneric species. Within L. wrightii, we obtained four lineages of ten haplotypes. These lineages and haplotypes did not correlate with the different flower colours. These results indicate that the formation processes of populations are complex. The haplotypes of the pink flower morph did not show a sister relationship between the two disjunct subregions, indicating that the disjunct populations of the pink flower morphs are unlikely to share the pink flower colour as a result of common ancestry. We conclude that the observed leapfrog distribution pattern is caused by natural selection and/or stochastic processes. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 709,717. [source] It is all in the head: morphological basis for differences in bite force among colour morphs of the Dalmatian wall lizardBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009KATLEEN HUYGHE Males of the lizard Podarcis melisellensis occur in three distinct colours that differ in bite performance, with orange males biting harder than white or yellow ones. Differences in bite force among colour morphs are best explained by differences in head height, suggesting underlying variation in cranial shape and/or the size of the jaw adductors. To explore this issue further, we examined variation in cranial shape, using geometric morphometric techniques. Additionally, we quantified differences in jaw adductor muscle mass. No significant differences in size corrected head shape were found, although some shape trends could be detected between the colour morphs. Orange males have relatively larger jaw adductors than yellow males. Not only the mass of the external jaw adductors, but also that of the internal jaw adductors was greater for the orange morph. Data for other cranial muscles not related to biting suggest that this is not the consequence of an overall increase in robustness in orange individuals. These results suggest that differences in bite performance among morphs are caused specifically by an increase in the mass of the jaw adductor, which may be induced by differences in circulating hormone levels. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 13,22. [source] Sexual dichromatism and male colour morph in ultraviolet-B reflectance in two populations of the jumping spider Phintella vittata (Araneae: Salticidae) from tropical ChinaBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2008JINGJING LI In the literature on animal use of ultraviolet (UV) vision and UV reflectance, it has usually been UV-A (315,400 nm) that is considered. Animals are generally assumed to be unable to discriminate UV-B (280,315 nm) from other wavelengths in natural sunlight. Recently, some animals are known to be able to detect and respond directly to UV-B in order to avoiding exposure to it. However, there is no evidence that the hue corresponding to UV-B is salient to an animal during intraspecies communication. Using Phintella vittata, an ornate jumping spider from two geographically different populations in China, we investigated geographical, intersexual, intrasexual, and interpopulation variation in UV reflectance. We found that both the males and the females of P. vittata reflect UV light, and that the reflection bands are located in UV-B, a part of reflectance spectrum never previously investigated. We also found a great deal of population variation in the UV-B spectral reflectance. Furthermore, two colour morphs, the ,green' and ,yellow' morphs, are identified for adult males for both populations, and both morphs differ greatly in both UV-B and human-visible wavelengths. This is the first demonstration of a UV-B reflecting salticid and UV-B sexual dichromatism. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 7,20. 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