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Ornamentation
Kinds of Ornamentation Selected AbstractsTHE EFFECTS OF GENOTYPE, AGE, AND SOCIAL ENVIRONMENT ON MALE ORNAMENTATION, MATING BEHAVIOR, AND ATTRACTIVENESSEVOLUTION, Issue 11 2005Lisa K. Miller Abstract The traits thought to advertise genetic quality are often highly susceptible to environmental variation and prone to change with age. These factors may either undermine or reinforce the potential for advertisement traits to signal quality depending on the magnitude of age-dependent expression, environmental variation, and genotype-age and genotype-environment interaction. Measurements of the magnitude of these effects are thus a necessary step toward assessing the implications of age dependence and environmental variability for the evolution of signals of quality. We conducted a longitudinal study of male guppies (Poecilia reticulata) from 22 full-sibling families. Each fish was assigned at maturity to one of three treatments in order to manipulate his allocation of resources to reproduction: a control in which the male was kept alone, a courtship-only treatment in which he could see and court a female across a clear partition, and a mating treatment in which he interacted freely with a female. We measured each male's size, ornamental color patterns, courtship, attractiveness to females, and mating success at three ages. Size was influenced by treatment and age-treatment interactions, indicating that courtship and mating may impose costs on growth. Tail size and color patterns were influenced by age but not by treatment, suggesting fixed age-dependent trajectories in these advertisement traits. By contrast, display rate and attempted sneak copulation rate differed among treatments but not among ages, suggesting greater plasticity of these behavioral traits. As a result of the different patterns of variation in ornamentation and behavior, male attractiveness and mating success responded to male age, treatment, and the interaction between age and treatment. Neither age nor treatment obscured the presence of genetic variation, and the genetic relationship between male ornamentation and attractiveness remained the same among treatments. Our findings suggest that neither age-dependent variation nor environmentally induced variation in reproductive effort is likely to undermine the reliability of male signaling. [source] OrnaMental POrnamentation: The Abstract and the Exuberant Body of OrnamentationARCHITECTURAL DESIGN, Issue 2 2010Marjan Colletti Abstract In the last few years, the introduction of new digital software has enabled the exuberant articulation of ornate surfaces and volumes. Marjan Colletti looks beyond technical innovation and observes a two-fold conceptual tendency that he labels the ,ornaMental' and the ,pOrnamentation', differentiating between the first's inclination to create form through abstraction and the latter's potential for the figural through sensation. Copyright © 2010 John Wiley & Sons, Ltd. [source] Antioxidants, showy males and sperm qualityECOLOGY LETTERS, Issue 5 2001Jonathan D. Blount The fertility of males sometimes correlates with their ornamental display, but we do not have a mechanistic explanation to universally link these traits. We suggest that both sperm quality (fertility; integrity of DNA), and the substrates responsible for male ornamentation, may be vulnerable to free radical attack, which can be mitigated by antioxidants. Support for these ideas is at present weak, and requires validation in ecological contexts. We hypothesize that a link between ornamentation and sperm quality could arise if antioxidants are in limited supply, and the showiest males may be preferred because they are most likely to be fertile, or to provide sperm with undamaged genotypes that could give rise to fit offspring. [source] Parental Effort in Relation to Structural Plumage Coloration in the Mountain Bluebird (Sialia currucoides)ETHOLOGY, Issue 9 2007Susan L. Balenger Indicator models of sexual selection suggest that costly ornaments signal reliable information regarding an individual's quality to potential mates. In species that produce altricial offspring, the amount of parental care provided by both males and females can impact reproductive success. The Good Parent Hypothesis proposes that ornamentation in biparental species can act as an honest signal of parental ability to potential mates. We tested this hypothesis using the mountain bluebird (Sialia currucoides), a sexually dichromatic, socially monogamous species in which both sexes have structurally based ornamental plumage coloration. A male's plumage color predicted neither the rate at which it provisioned nestlings nor brood growth rate. The same was true for females. We also found no indication of assortative mating by color or body condition. Feeding rates within pairs were positively correlated, which we suggest may be due to pairs responding similarly to the perceived needs of nestlings or to local area prey availability. In sum, our results do not support the Good Parent Hypothesis as an explanation for the evolution of ornamental plumage color in mountain bluebirds. We suggest alternative hypotheses for the evolution of ornamental plumage color in this species. [source] Intra- and Intersexual Selection for Multiple Traits in the Peacock (Pavo cristatus)ETHOLOGY, Issue 9 2005Adeline Loyau Animal communication involves a multitude of signals ranging from morphological to behavioural traits. In spite of the diversity of traits used in animal signalling, most studies of sexual selection have focused on single male traits. Moreover, the two forces of sexual selection (male,male competition and female preference) may target different traits and favour the diversification of male signalling. Still, little is known on the combined effects of intra- and intersexual selection on the evolution of multiple signals. The peacock is often cited as one of the best examples of the strength of sexual selection in producing exaggerated traits. Here, we investigated traits under intra- and intersexual selection in a population of free-ranging common peafowl. Peacocks with longer trains and tarsi were more likely to establish a display territory in a central position within the lek and had a higher number of intrusions and agonistic interactions. These traits appeared therefore to be under intrasexual selection. Female selection was assessed as the number of copulations. Mating success was positively correlated with behavioural traits (display activity) and with train ornamentation (number and density of ocelli) suggesting that females use multiple cues during mate selection. Therefore, intra- and intersexual selection seem to operate on different sets of traits. Overall, our results stress the role of multiple receivers on the evolution of multiple signals. [source] Breeding Tubercles, Papillomatosis and Dominance Behaviour of Male Roach (Rutilus rutilus) During the Spawning PeriodETHOLOGY, Issue 8 2004Raine Kortet We studied the relationship between the breeding tubercle ornamentation (i.e. skin roughness) and male pre-spawning dominance and courtship behaviour in roach (Rutilus rutilus) within an experimental laboratory system. Sexually mature fish were caught during their migration to their spawning pond and their behaviours were studied in an artificial spawning arena. Males behaved naturally both in terms of male,male interactions and attempts to achieve spawnings. Males having many, large breeding tubercles (i.e. rough skin) were significantly more often dominant in our dyadic trials than those with smooth skin. The dominant male in the trial exhibited a more active courtship behaviour than its subordinate rival. Papilloma skin disease did not affect the dominance rank. As a result of the relationship between skin roughness and male dominance, breeding tubercles may be used by the females as a cue for choosing a high-quality mate in a roach lek. Thus, breeding tubercles might offer a workable tool for examination of sexual selection among cyprinids. [source] THE EFFECTS OF GENOTYPE, AGE, AND SOCIAL ENVIRONMENT ON MALE ORNAMENTATION, MATING BEHAVIOR, AND ATTRACTIVENESSEVOLUTION, Issue 11 2005Lisa K. Miller Abstract The traits thought to advertise genetic quality are often highly susceptible to environmental variation and prone to change with age. These factors may either undermine or reinforce the potential for advertisement traits to signal quality depending on the magnitude of age-dependent expression, environmental variation, and genotype-age and genotype-environment interaction. Measurements of the magnitude of these effects are thus a necessary step toward assessing the implications of age dependence and environmental variability for the evolution of signals of quality. We conducted a longitudinal study of male guppies (Poecilia reticulata) from 22 full-sibling families. Each fish was assigned at maturity to one of three treatments in order to manipulate his allocation of resources to reproduction: a control in which the male was kept alone, a courtship-only treatment in which he could see and court a female across a clear partition, and a mating treatment in which he interacted freely with a female. We measured each male's size, ornamental color patterns, courtship, attractiveness to females, and mating success at three ages. Size was influenced by treatment and age-treatment interactions, indicating that courtship and mating may impose costs on growth. Tail size and color patterns were influenced by age but not by treatment, suggesting fixed age-dependent trajectories in these advertisement traits. By contrast, display rate and attempted sneak copulation rate differed among treatments but not among ages, suggesting greater plasticity of these behavioral traits. As a result of the different patterns of variation in ornamentation and behavior, male attractiveness and mating success responded to male age, treatment, and the interaction between age and treatment. Neither age nor treatment obscured the presence of genetic variation, and the genetic relationship between male ornamentation and attractiveness remained the same among treatments. Our findings suggest that neither age-dependent variation nor environmentally induced variation in reproductive effort is likely to undermine the reliability of male signaling. [source] A palynological study of Galium L. (Rubiaceae) in Egypt and its systematic implicationFEDDES REPERTORIUM, Issue 7-8 2007K. Abdel Khalik A pollen morphological investigation of eleven species and one subspecies of the genus Galium L. from Egypt were undertaken by using light microscope (LM) and scanning electron microscope (SEM). Pollen shape, size, exine ornamentation, number of apertures present powerful characters for distinguishing between species. The pollen grains were zonocolpate. The number of colpi ranges from 5 to 10. Their shape varies from prolate spheroidal, oblate spheroidal, spheroidal to suboblate. Three groups can be distinguished based on the size pollen grains. It was found used to distinguish between closely related species G. aparine and G. spurium and between G. tricornutum and G. ceratopodum. Two different types of exine ornamentation were recognized. The ornamentation was found useful to distinguish among closely related species such as Galium aparine and G. spurium. A key for the identification of the investigated taxa based on pollen grains characters is provided. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Eine palynologische Studie der Gattung Galium L. (Rubiaceae) in Ägypten und ihre Bedeutung für die Systematik Die Pollenmorphologie von elf Arten und einer Unterart der Gattung Galium L. aus Ägypten wurde mittels Licht- und Elektronenmikroskopie untersucht. Pollenform, Größe und Muster der Exine und die Anzahl der Aperturen repräsentieren gute Merkmale zur Unterscheidung der betrachteten Arten. Alle Pollen sind zonocolpat. Die Anzahl der Colpi liegt zwischen 5 bis 10. Ihre äußere Form variiert von prolat über sphäroidal, oblat-sphäroidal, sphäroidal bis suboblat. Auf Grund der Pollengröße lassen sich drei Gruppen unterscheiden. Es zeigte sich, dass diese drei Gruppen genutzt werden können, um die eng verwandten Arten Galium aparine und G. spurium sowie G.tricornatum und G. ceratopodum von einander zu trennen. Zwei Typen der Exine-Muster ließen sich erkennen. Sie sind geeignet um z. B. so eng verwandte Arten wie Galium aparine und G. spurium zu trennen. Ein Schlüssel, der geeignet ist, die untersuchten Taxa auf der Basis ihrer Pollenmerkmale zu bestimmen beschließt die Arbeit. [source] Parasites, testosterone and honest carotenoid-based signalling of healthFUNCTIONAL ECOLOGY, Issue 5 2007F. MOUGEOT Summary 1Among the commonest sexual signals of birds are the red-yellow traits pigmented by carotenoids, but how they reliably advertise individual quality remain poorly understood. Here we tested the hypothesis that carotenoid-based signalling is enhanced by testosterone but reduced by parasites, and that the dual action of testosterone on ornament expression and parasite resistance ensures reliable signalling. 2Tetraonid birds such as the red grouse Lagopus lagopus scoticus have bright red combs pigmented by carotenoids, which function in intra- and inter-sexual selection. In separate experiments, we manipulated a main nematode parasite, Trichostrongylus tenuis (using deparasitation and re-infection) and testosterone (using testosterone or combined Flutamide/ATD treatments) in free-living males and investigated effects on plasma carotenoids and comb colour. 3In untreated males, comb redness positively correlated with plasma carotenoids, testosterone concentration and condition. Plasma carotenoids and comb redness both negatively correlated with T. tenuis abundance. 4Plasma carotenoids decreased in response to a challenge from T. tenuis, but increased when parasites were reduced. Testosterone enhanced comb redness, but tended to deplete plasma carotenoids. Combined Flutamide and ATD treatment had no significant effects on comb colour or plasma carotenoids, indicating that testosterone effects might be direct. 5Our experiments show contrasted effects of testosterone and nematode parasites on carotenoid-based ornamentation. Testosterone and parasites have well documented interactions in the study model. These, together with the opposite effects that testosterone and parasites have on carotenoid availability and use, would shape optimal levels of signalling, depending on individual quality, and might ensure reliable signalling. 6Carotenoid-based and testosterone-dependent traits have rarely been linked. Our study provides such a connection and shows that investigating how parasites, testosterone and carotenoids interact helps in the understanding of the evolution and maintenance of honest carotenoid-based signals of health. [source] Does female nuptial coloration reflect egg carotenoids and clutch quality in the Two-Spotted Goby (Gobiusculus flavescens, Gobiidae)?FUNCTIONAL ECOLOGY, Issue 4 2006P. A. SVENSSON Summary 1Carotenoid-based ornamentation has often been suggested to signal mate quality, and species with such ornaments have frequently been used in studies of sexual selection. 2Female 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. 3We 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. 4Eggs 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. 5Colourful 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. 6Our results call into question the generality of a causal link between egg carotenoids and offspring quality. [source] Nest ornamentation by female spotless starlings in response to a male display: an experimental studyJOURNAL OF ANIMAL ECOLOGY, Issue 4 2006VICENTE POLO Summary 1The use of behavioural traits by females in signalling condition has been practically ignored in evolutionary theory. However, females may also exhibit ornaments and behavioural displays, although less elaborated than those of males. 2In this study we suggest that the carrying of feathers by spotless starlings Sturnus unicolor Temminck females to decorate the nest represents an elaborated and costly behaviour that is displayed in response to a courtship male behaviour: the carrying of nest green plants. 3By experimentally increasing the amount of green plants in the nests, to give the appearance that highly attractive males defended them, we induced females to increase their feather carrying rates. 4The amount of feathers carried to the nest was correlated to female reproductive experience and laying date, two variables correlated with female body condition. These results suggests that this behaviour may work as an honest indicator of female quality. 5We conclude that male carrying plants and female carrying feathers can be viewed as two sex-specific functionally related signalling behaviours involved in mutual courtship or status signalling. [source] Temporal variation in glucocorticoid levels during the resting phase is associated in opposite way with maternal and paternal melanic colorationJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 10 2010A. ROULIN Abstract Sex-dependent selection can help maintain sexual dimorphism. When the magnitude of selection exerted on a heritable sex trait differs between the sexes, it may prevent each sex to reach its phenotypic optimum. As a consequence, the benefit of expressing a sex trait to a given value may differ between males and females favouring sex-specific adaptations associated with different values of a sex trait. The level of metabolites regulated by genes that are under sex-dependent selection may therefore covary with the degree of ornamentation differently in the two sexes. We investigated this prediction in the barn owl, a species in which females display on average larger black spots on the plumage than males, a heritable ornament. This melanin-based colour trait is strongly selected in females and weakly counter-selected in males indicating sex-dependent selection. In nestling barn owls, we found that daily variation in baseline corticosterone levels, a key hormone that mediates life history trade-offs, covaries with spot diameter displayed by their biological parents. When their mother displayed larger spots, nestlings had lower corticosterone levels in the morning and higher levels in the evening, whereas the opposite pattern was found with the size of paternal spots. Our study suggests a link between daily regulation of glucocorticoids and sex-dependent selection exerted on sexually dimorphic melanin-based ornaments. [source] Honest olfactory ornamentation in a female-dominant primateJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 7 2010M. BOULET Abstract Sexual selection theory predicts that potential mates or competitors signal their quality to conspecifics. Whereas evidence of honest visual or vocal signals in males abounds, evidence of honest signalling via scent or by females is scarce. We previously showed that scent marks in male lemurs seasonally encode information about individual heterozygosity , a reliable predictor of immunocompetence and survivorship. As female lemurs dominate males, compete over resources, and produce sexually differentiated scent marks that likely evolved via direct selection, here we tested whether females also advertise genetic quality via olfactory cues. During the breeding season specifically, individual heterozygosity correlated negatively with the diversity of fatty acids (FAs) expressed in labial secretions and positively with the diversity of heavy FA esters. As odour,gene relationships predictive of health and survivorship emerged during a period critical to mate choice and female competition, we posit that genital scent marks function as honest olfactory ornaments in females. [source] Condition-dependent mutation rates and sexual selectionJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2009S. COTTON Abstract ,Good genes' models of sexual selection show that females can gain indirect benefits for their offspring if male ornaments are condition-dependent signals of genetic quality. Recurrent deleterious mutation is viewed as a major contributor to variance in genetic quality, and previous theoretical treatments of ,good genes' processes have assumed that the influx of new mutations is constant. I propose that this assumption is too simplistic, and that mutation rates vary in ways that are important for sexual selection. Recent data have shown that individuals in poor condition can have higher mutation rates, and I argue that if both male sexual ornaments and mutation rates are condition-dependent, then females can use male ornamentation to evaluate their mate's mutation rate. As most mutations are deleterious, females benefit from choosing well-ornamented mates, as they are less likely to contribute germline-derived mutations to offspring. I discuss some of the evolutionary ramifications of condition-dependent mutation rates and sexual selection. [source] Carotenoid and protein supplementation have differential effects on pheasant ornamentation and immunityJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 1 2007H. G. SMITH Abstract A currently popular hypothesis states that the expression of carotenoid-dependent sexual ornaments and immune function may be correlated because both traits are positively affected by carotenoids. However, such a correlation may arise for another reason: it is well known that immune function is dependent on nutritional condition. A recent study has suggested that the expression of ornaments may too depend on nutritional condition, as males in good nutritional condition are better at assimilating and/or modulating carotenoids. Thus, carotenoid-dependent ornaments and immune function may be correlated because both are dependent on nutritional condition. To elucidate if, and how, ornamentation and immune function are linked, pheasant diets were supplemented with carotenoid and/or protein in a fully factorial experiment. Carotenoid treatment affected wattle coloration and tail growth, but not cellular or humoral immunity. Immunity was unrelated to males' initial ornamentation including wattle colour. Males in better body condition, measured as residual mass, increased their wattle coloration more when carotenoid supplemented. Protein positively affected humoral but not cellular immunity, but had no effect on ornaments. Cellular, but not humoral, immunity increased with male body condition. Thus, there was no evidence that an immune-stimulatory effect of carotenoids resulted in wattle coloration honestly signalling immune function, but wattle coloration may still signal male body condition. [source] Context-dependent sexual advertisement: plasticity in development of sexual ornamentation throughout the lifetime of a passerine birdJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2003A. V. Badyaev Abstract Male investment into sexual ornamentation is a reproductive decision that depends on the context of breeding and life history state. In turn, selection for state- and context-specific expression of sexual ornamentation should favour the evolution of developmental pathways that enable the flexible allocation of resources into sexual ornamentation. We studied lifelong variation in the expression and condition-dependence of a sexual ornament in relation to age and the context of breeding in male house finches (Carpodacus mexicanus) , a species that develops a new sexual ornament once a year after breeding. Throughout males' lifetime, the elaboration of ornamentation and the allocation of resources to the development of sexual ornamentation depended strongly on pairing status in the preceding breeding season , males that were single invested more resources into sexual ornamentation and changed ornamentation more than males that were paired. During the initial (post-juvenile) moult, the expression of ornamentation was closely dependent on individual condition, however the condition-dependence of ornamentation sharply decreased throughout a male's lifetime and in older males expression of sexual ornamentation was largely independent of condition during moult. Selection for early breeding favoured greater ornamentation in males that were single in the preceding seasons and the strength of this selection increased with age. On the contrary, the strength of selection on sexual ornamentation decreased with age in males that were paired in the preceding breeding season. Our results reveal strong context-dependency in investment into sexual ornamentation as well as a high flexibility in the development of sexual ornamentation throughout a male's life. [source] Inbreeding depression and genetic load of sexually selected traits: how the guppy lost its spotsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2003C. Van Oosterhout Abstract To date, few studies have investigated the effects of inbreeding on sexually selected traits, although inbreeding depression on such traits can play an important role in the evolution and ecology of wild populations. Sexually selected traits such as ornamentation and courtship behaviour may not be primary fitness characters, but selection and dominance coefficients of their mutations will resemble those of traits under natural selection. Strong directional selection, for instance, through female mate-choice, purges all but the most recessive deleterious mutations, and the remaining dominance variation will result in inbreeding depression once populations undergo bottlenecks. We analysed the effects of inbreeding on sexually selected traits (colour pattern and courtship behaviour) in the male guppy, Poecilia reticulata, from Trinidad, and found a significant decline in the frequency of mating behaviour and colour spots. Such effects occurred although the genetic basis of these traits, many of which are Y-linked and hemizygous, would be expected to leave relatively little scope for inbreeding depression. Findings suggest that these sexually selected traits could reflect the genetic condition or health of males, and thus may be informative mate-cue characters for female choice as suggested by the ,good genes' model. [source] Fishes as models in studies of sexual selection and parental careJOURNAL OF FISH BIOLOGY, Issue 2003T. Amundsen Fishes are by far the most diverse group of vertebrates. This fact is in no way, however, reflected in their use as model organisms for understanding sexual selection or parental care. Why is this so? Is it because fishes are actually poor models? The usefulness of fishes as models for sexual selection and parental care is discussed by emphasizing some problems inherent in fish studies, along with a number of reasons why fishes are indeed excellently suited. The pros and cons of fishes as models are discussed mainly by comparison with birds, the most popular model organisms in animal behaviour. Difficulties include a lack of background knowledge for many species, and the problems of marking and observing fishes in their natural environment. Positive attributes include the diversity of lifestyles among fishes, and the ease with which they can be studied experimentally in the laboratory. How useful fish models can be is briefly illustrated by the impressive and broadly relevant advances derived from studies of guppies Poecilia reticulata and three-spined sticklebacks Gasterosteus aculeatus. A selection of topics is highlighted where fish studies have either advanced or could greatly enhance, the understanding of processes fundamental to animal reproductive dynamics. Such topics include sex role dynamics, the evolution of female ornamentation and mate choice copying. Finally, a number of potential pitfalls in the future use of fish as models for sexual selection and parental care are discussed. Researchers interested in these issues are recommended to make much more extensive use of fish models, but also to adopt a wider range of models among fishes. [source] ULTRASTRUCTURE AND LSU rDNA,BASED REVISION OF PERIDINIUM GROUP PALATINUM (DINOPHYCEAE) WITH THE DESCRIPTION OF PALATINUS GEN.JOURNAL OF PHYCOLOGY, Issue 5 2009The name Peridinium palatinum Lauterborn currently designates a freshwater peridinioid with 13 epithecal and six cingular plates, and no apical pore complex. Freshwater dinoflagellate floras classify it in Peridinium group palatinum together with P. pseudolaeve M. Lefèvre. General ultrastructure, flagellar apparatus, and pusular components of P. palatinum were examined by serial section TEM and compared to P. cinctum (O. F. Müll.) Ehrenb. and Peridiniopsis borgei Lemmerm., respectively, types of Peridinium and Peridiniopsis. Partial LSU rDNA sequences from P. palatinum, P. pseudolaeve and several peridinioids, woloszynskioids, gymnodinioids, and other dinoflagellates were used for a phylogenetic analysis. General morphology and tabulation of taxa in group palatinum were characterized by SEM. Differences in plate numbers, affecting both the epitheca and the cingulum, combine with differences in plate ornamentation and a suite of internal cell features to suggest a generic-level distinction between Peridinium group palatinum and typical Peridinium. The branching pattern of the phylogenetic tree is compatible with this conclusion, although with low support from bootstrap values and posterior probabilities, as are sequence divergences estimated between species in group palatinum, and typical Peridinium and Peridiniopsis. Palatinus nov. gen. is proposed with the new combinations Palatinus apiculatus nov. comb. (type species; syn. Peridinium palatinum), P. apiculatus var. laevis nov. comb., and P. pseudolaevis nov. comb. Distinctive characters for Palatinus include a smooth or slightly granulate, but not areolate, plate surface, a large central pyrenoid penetrated by cytoplasmic channels and radiating into chloroplast lobes, and the presence of a peduncle-homologous microtubular strand. Palatinus cells exit the theca through the antapical-postcingular area. [source] Morphological and molecular examination of relationships and epitype establishment of Phacus pleuronectes, Phacus orbicularis, and Phacus hamelii,JOURNAL OF PHYCOLOGY, Issue 5 2007Sylwia Kosmala Verification of morphological diagnostic features and the establishment of three epitypes for three species of Phacus Dujardin,Phacus pleuronectes (O. F. Müll.) Dujardin, Phacus orbicularis Hübner, and Phacus hamelii Allorge et Lefèvre,was performed based on literature studies and analysis of morphological (cell shape, cell size, and periplast ornamentation) as well as molecular (18S rDNA) characters. Periplast ornamentation was recognized as a main diagnostic character, distinguishing P. orbicularis from P. pleuronectes and P. hamelii. Phacus orbicularis has struts running perpendicular to the longitudinal axis of the strips, while P. pleuronectes and P. hamelii do not. On the SSU rDNA tree, obtained by the Bayesian method, P. orbicularis, P. pleuronectes, and P. hamelii belong to three distinct clades. Some of the phylogenetic relationships are not resolved, but there are at least three Phacus species (P. hamatus, P. platyaulax, P. longicauda; for taxonomic authors, see Introduction) that are more closely related to P. orbicularis than is P. pleuronectes. Phacus hamelii is more closely related to P. ranula and the assemblage of several species of Phacus, which have small cells, than to P. orbicularis or P. pleuronectes. [source] TAXONOMIC REEXAMINATION OF 17 SPECIES OF NITELLA SUBGENUS TIEFFALLENIA (CHARALES, CHAROPHYCEAE) BASED ON INTERNAL MORPHOLOGY OF THE OOSPORE WALL AND MULTIPLE DNA MARKER SEQUENCES,JOURNAL OF PHYCOLOGY, Issue 1 2005Hidetoshi Sakayama In an attempt to reconstruct the natural taxonomic system for Nitella, 17 species of Nitella subgenus Tieffallenia were reexamined using SEM observations of the internal morphology of the oospore wall (IMOW) and phylogenetic analyses of 4553 base pairs from multiple DNA markers (atpB, rbcL, psaB, and ITS-5.8S rRNA genes). Our SEM observations identified three types of IMOW: homogeneous (HG), weakly spongy (W-SG), and strongly spongy (S-SG) types. Based on differences in the IMOW, species with reticulate or tuberculate oospore wall ornamentation in the external morphology of the oospore wall (EMOW) were subdivided into two distinct groups (characterized by the HG or S-SG types of IMOW, respectively), which were robustly separated from each other in our molecular phylogenetic analyses. In our molecular phylogeny, the subgenus Tieffallenia consisted of four robust monophyletic groups,three clades of the HG type and a spongy (S-SG and W-SG) type clade,that were characterized by differences in the IMOW and EMOW. In addition, our SEM observations and sequence data verified the distinct status of five species (N. japonica Allen, N. oligospira A. Braun, N. vieillardii stat. nov., N. imperialis stat. nov., and N. morongii Allen) that R. D. Wood had assigned as infraspecific taxa. Moreover, our SEM observations of the IMOW also suggested that N. megaspora (J. Groves) Sakayama originally identified by LM includes at least two distinct species, characterized by W-SG and S-SG types of IMOW, respectively. [source] Intrafloral differentiation of stamens in heterantherous flowersJOURNAL OF SYSTEMATICS EVOLUTION, Issue 1 2009Zhong-Lai LUO Abstract Flowers that have heteromorphic stamens (heterantherous flowers) have intrigued many researchers ever since the phenomenon was discovered in the 19th century. The morphological differentiation in androecia has been suggested as a reflection of "labor division" in pollination in which one type of stamens attracts pollinators and satisfies their demand for pollen as food and the other satisfies the plant's need for safe gamete dispersal. The extent and patterns of stamen differentiation differ notably among taxa with heterantherous flowers. Seven species with heteromorphic stamens in three genera were sampled from Leguminosae and Melastomataceae, and the morphological difference of androecia, pollen content, pollen histochemistry and viability, pollen micro-morphology, as well as the main pollinators were examined and compared. Pollen number differs significantly between stamen sets of the same flower in most species investigated, and a correlation of pollen number and anther size was substantiated. Higher pollen viabilities were found in the long (pollinating) stamens of Senna alata (L.) Roxb. and S. bicapsularis (L.) Roxb. Dimorphic pollen exine ornamentation is reported here for the first time in Fordiophyton faberi Stapf. The height of stigma and anther tips of the long stamens in natural conditions was proved to be highly correlated, supporting the hypothesis that they contact similar areas of the pollinator's body. [source] Penile morphology of African mole rats (Bathyergidae): structural modification in relation to mode of ovulation and degree of socialityJOURNAL OF ZOOLOGY, Issue 2 2006A. Parag Abstract The penile morphology and bacular structure of five species of African mole rat are described in relation to the method of ovulation, degree of sociality and polygynandry. We predicted that, with an increase in sociality, and a concomitant decrease in polygynandry and sperm competition, there would be a decrease in penis ornamentation (spinosity) and baculum size. In solitary species of African mole rat with marked seasonal reproduction and induced ovulation (Bathyergus suillus and Georychus capensis), males have numerous epidermal spines on the penis. Social, seasonally breeding, induced ovulating mole rats Cryptomys hottentotus natalensis possess less elaborate ornamentation in the form of small protrusions that are rounded at the apex. Two aseasonally breeding eusocial species with spontaneous ovulation Cryptomys damarensis and Heterocephalus glaber have ridges on the penis but lack any elaborate ornamentation. Baculae, however, showed a trend to become proportionally smaller in the solitary species. Our prediction that, with an increase in sociality and a move from induced to spontaneous ovulation, the amount and degree of penile ornamentation declines was, therefore, generally supported. [source] Models for the morphogenesis of the molluscan shellLETHAIA, Issue 2 2005ØYVIND HAMMER We give a review of current theories of morphogenesis of both the general coiling and the ornamentation of molluscan shells. These two aspects of shell growth are closely connected, as ornamentation is primarily due to local perturbations of the general apertural growth field controlling coiling. Also, a new, generalized, free-form apertural growth map model is presented in this paper, illustrating some aspects of the regulation of logarithmic spiral growth. This model is used to simulate the formation of megastriae in ammonoids. We emphasize the importance of damaged specimens and how they regenerated, as illustrated with examples from ammonoids. The phenomenon of ornamental compensation can be explained by a mechanism involving a pre-pattern in the mantle. However, simple reaction-diffusion models for ornamental pattern formation should be regarded only as useful abstractions. [source] Perspectives of ammonite paleobiology from shell abnormalities in the genus BaculitesLETHAIA, Issue 3 2002R.A. HENDERSON Many Baculites specimens from the Upper Cretaceous of the United States Western Interior show exceptional preservation of the original aragonitic shell and its fine-scale surface ornamentation. Growth lines are ubiquitous, with two orders of these structures represented on some shells, and reflect the incremental addition of new shell at the apertural margin. Growth line interruption in the form of repair of minor shell damage at the aperture, commonplace in contemporary Nautilus, is essentially absent in Baculites, suggesting that its members fed on small prey in the water column. As typical of Mesozoic ammonites in general, and in striking contrast to contemporary Nautilus, no in vivo epizoans have been recognized on specimens of Baculites. It is inferred that the shell of Baculites was covered in periostracum to eliminate epizoic colonization. By analogy with Nautilus, a distinctive micro-ornament oriented at right angles to growth lines and visible on parts of some specimens was probably associated with periostracal attachment. A small proportion of Baculites specimens show abnormalities in shell growth categorized as v-shaped indentations of growth lines, shell grooves, fine-scale folds on the surface of growth lines and feather structures. We view this entire set of structures as due to abnormalities in mantle growth induced at the leading edge, impressed into the periostracum during its fabrication, and then in turn into the shell surface. As many of the Baculites with shell abnormalities are smooth, the proposal by Checa linking homologous structures recognized on other ammonites to the formation of comarginal ribs is rejected. A case of sutural inversion, in which the form of minor divisions of the major saddles and lobes are transposed, is recognized in a specimen of Baculites codyensis Reeside. We consider sutural pattern in ammonites, an expression of septal fluting, as replicating the genetically specified standing form of an elastic adapical visceral mass. The inverted sutural pattern, and by implication the style of septal fluting, was transcribed exactly in the three successive septa preserved on the specimen. The abnormality appears to be a case of homeotic mutation in which the plan for one body region becomes translocated to another. The conservatism of major elements of sutural (=septal) patterns for Mesozoic ammonites in their evolutionary spectrum suggests that a homeobox of conserved DNA sequence, with the transcription factors encoded in homeotic genes, is likely to have been involved. [source] Post-pathological keel-loss compensation in ammonoid growthLETHAIA, Issue 1 2002ALAIN MORARD Among the various pathologies documented in ammonoids, impairs affecting the apertural margin may have long-lasting sequelae on subsequent shell geometry. An interesting healing pattern, known as sculptural compensation, led to the permanent replacement of an ornament by adjacent sculptural elements. Moreover, in several ventrally impaired individuals the symmetry was preserved. Those developed annular ribs in place of any previous ventral ornamentation (keel, sulcus or smooth area). This phenomenon is known from diverse ammonite families. Monestieria resouchei (Monestier 1931), type species of ,Monestieriinae' Sapunov 1965, displays exactly that type of annularly-ribbed morphology and has been shown to be otherwise similar to species of Grammoceratinae Buckman 1904 occurring in the same beds, thus corroborating its pathological nature and leading to the rejection of that taxon. Now, keel absence in Praehaploceras Monestier 1931 and Buckmanites Guex 1973 cannot be explained by the same process as they do not have annular ribs. Moreover, the absence of any clue of malformation, their relative frequency and specific characteristics exclude the previously suggested synonymies with Pseudolioceras Buckman 1889 as equivalent pathological forms. In consequence, their rehabilitation is herein proposed. They should be included within Harpoceratinae Neumayr 1875. [source] Origin and phylogeny of Guyniidae (Scleractinia) in the light of microstructural dataLETHAIA, Issue 1 2000Jaros, aw Stolarski The set of skeletal characters of the Recent azooxanthellate coral Guynia annulata Duncan, 1872 is unique among extant scleractinians and encompasses: (a) undifferentiated septal calcification centers (in most extant scleractinians calcification centers are clearly separated); (b) completely smooth septal faces (septa of almost all extant scleractinians bear granular ornamentation); (c) deeply recessed septa in respect to the epithecal rim in the adult coralla (in adults of the majority of extant scleractinians the relationships between septa and wall are the reverse); and (d) an aseptal part of the initial ontogenetic stage, just above the basal plate (almost all known scleractinians have a septate initial coralla). Skeletal features of five other extant traditional guyniids are typical of other caryophylliines (and of Scleractinia). However, the wall types present in different species of traditional guyniids exceed limits traditionally attributed to one caryophylliine family: i.e., Stenocyathus and Truncatoguynia have a marginothecal wall like the Flabellidae, whereas Schizocyathus and Temnotrochus usually have an entirely epithecal wall, as in Gardineriidae (Volzeioidea). Moreover, Pourtalocyathus and Schizocyathus show intraspecific variation in distribution of septal calcification centers (separated vs. non-separated) and in wall types (epithecal vs. consisting of large spherulite-like bodies). These major differences in skeletal architecture form the basis for a new, threefold taxonomical subdivision of the traditional guyniids: (1) Guyniidae Hickson, 1910, containing only monospecific Guynia with an epithecal wall, and septa with non-separated calcification centers; (2) Schizocyathidae fam.n., groups Microsmilia Schizocyathus, Pourtalocyathus, Temnotrochus, which have an epithecal wall and septa with usually well-separated calcification centers; and (3) Stenocyathidae fam.n. with Stenocyathus and Truncatoguynia which have a marginothecal wall and septa with well-separated calcification centers. Despite differences in the basic architecture of the skeleton, all taxa attributed to these families have ,thecal pores' formed by selective dissolution of the skeleton. I propose two hypotheses for evolutionary relationships among Guyniidae, Schizocyathidae, and Stenocyathidae: (1) Hypothesis A: the three families are not phylogenetically related and ,pores' originated independently in different scleractinian lineages: e.g., Guyniidae may represent distant zardinophyllid or gigantostyliid descendants, Schizocyathidae may be a volzeioid offshoot, whereas Stenocyathidae may be a flabellid descendant; (2) Hypothesis B: the three families are phylogenetically related and ,thecal pores' are synapomorphic for the clade (superfamily Guynioidea). Additional approaches, such as anatomical observations, molecular studies on guyniid DNA sequences, and in-depth studies on scleractinian biomineralization will be necessary to test these hypotheses. [source] "Where Theologians Fear to Tread"MODERN THEOLOGY, Issue 1 2000Amy Plantinga Pauw This essay appeals to the practice of Baroque musical ornamentation as an analogy to the place of reflection on angels and demons in Christian theology. In ways left to the discretion of the performer, this reflection functions to enhance the main theological melody of God, Christ, human salvation, and, in particular, eschatology. Jonathan Edwards and Karl Barth are the text cases for this thesis. While Edwards' treatment of angels and Satan mutes his eschatology of glory by drawing attention to the humility and suffering of Christ, Barth's treatment underscores the sovereignty of God and Christ's victory over sin. [source] A NEW SPINICAUDATAN GENUS (CRUSTACEA: ,CONCHOSTRACA') FROM THE LATE CRETACEOUS OF MADAGASCARPALAEONTOLOGY, Issue 5 2008ALYCIA L. STIGALL Abstract:, A new spinicaudatan genus and species, Ethmosestheria mahajangaensis gen. et sp. nov., is described from the Anembalemba Member (Upper Cretaceous, Maastrichtian) of the Maevarano Formation, Mahajanga Basin, Madagascar. This is the first spinicaudatan reported from the post-Triassic Mesozoic of Madagascar. The new species is assigned to the family Antronestheriidae based on the cavernous or sievelike ornamentation on the carapace. Of well-documented Mesozoic spinicaudatan genera, Ethmosestheria mahajangaensis is most closely related to Antronestheria Chen and Hudson from the Great Estuarine Group (Jurassic) of Scotland. However, relatively poor documentation of the ornamentation of most Gondwanan Mesozoic spinicaudatan species precludes detailed comparison among taxa. Ethmosestheria mahajangaensis exhibits ontogenetic trends in carapace growth: a change in carapace outline from subcircular/subelliptical to elliptical, and from very wide juvenile growth bands to narrow adult growth bands. Ornamentation style, however, does not vary with ontogeny. Ethmosestheria mahajangaensis individuals lived in temporary pools in a broad channel-belt system within a semiarid environment; preserved desiccation structures on carapaces indicate seasonal drying out of pools within the river system. Specimens of Ethmosestheria mahajangaensis are preserved with exquisite detail in debris flow deposits; these are the first spinicaudatans reported from debris flow deposits. These deposits also contain a varied vertebrate fauna, including dinosaurs, crocodyliforms, turtles, and frogs. Rapid entombment of the spinicaudatan carapaces likely promoted early fossil diagenesis leading to highly detailed preservation. [source] A new species of Karydomys (Rodentia, Mammalia) and a systematic re-evaluation of this rare Eurasian Miocene hamsterPALAEONTOLOGY, Issue 6 2004Thomas Mörs We describe a new species of the rare and enigmatic cricetid genus Karydomys from the middle Miocene Ville Formation of the Hambach lignite mine in north-west Germany. The locality Hambach 6C has yielded the first substantial records of Karydomys from central Europe. For the first time, all molar positions are well-documented, including the previously unknown m2. The excellent molar material allows us to distinguish Karydomys wigharti sp. nov. from the western European species K. zapfei. Karydomys wigharti predominantly occurs at localities that are correlated with the upper part of the Mammalian Neogene biozone MN 5. The new finds are of palaeobiogeographic significance for the genus Karydomys, since Hambach 6C represents the north-westernmost outpost of terrestrial Miocene faunas in Europe. In addition, the locality has yielded the first lower jaws and incisors of the genus. Both the jaw morphology, and the ornamentation and microstructure of the incisor enamel offer new arguments for a systematic classification of Karydomys into the subfamily Democricetodontinae. We assume that the scarcity of the two large European Karydomys species can be explained by their special adaptation to wet habitats, which are poorly documented in the fossil record. [source] | |||||||||||||||||||||||||||||||