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BudrienÄ—, Anna
This paper represents an initial attempt to examine mating phases of ten wasp species of the genera Ancistrocerus, Discoelius and Symmorphus, posing the questions as to what species traits are potentially involved in interactions between sexes, and what forms of sexual selection impel the evolution of these traits. The studied ...
Soler J J - - 2012
Wallace proposed in 1868 that natural rather than sexual selection could explain the striking differences in avian plumage dichromatism. Thus, he predicted that nesting habits, through their association with nest predation, could drive changes in sexual dichromatism by enabling females in cavity nesters to become as conspicuous as males, whereas ...
Collet Julie - - 2012
In principle, widespread polyandry (female promiscuity) creates potential for sexual selection in males both before and after copulation. However, the way polyandry affects pre- and postcopulatory episodes of sexual selection remains little understood. Resolving this fundamental question has been difficult because it requires extensive information on mating behavior as well ...
Gluckman Peter D - - 2012
The application of evolutionary thinking to human physical and psychological medicine suggests several pathways through which evolutionary processes affect risk of disease. Among these is the concept of mismatch between an individual and its environment, either because the environment has changed for the whole species (evolutionary novelty) or because the ...
Jašarević Eldin - - 2012
The timing of reproductive development and associated trade-offs in quantity versus quality of offspring produced across the life span are well documented in a wide range of species. The relation of these aspects of maternal life history to monogamy and paternal investment in offspring is not well studied in mammals, ...
Hosokawa Takahiro - - 2012
Symbiotic bacteria associated with midgut crypts of stinkbugs of the family Cydnidae, representing seven species and thirteen populations, were investigated. All the symbionts were species-specific, and constituted at least four distinct lineages in the Gammaproteobacteria, indicating multiple evolutionary origins of the gut symbionts among the burrower bugs.
Bannikov Alexandre F - - 2012
The Paleocene-Eocene transition is of crucial interest for interpreting the Cenozoic evolutionary radiation of vertebrates. A substantial increase of the number of vertebrate families occurred between the Late Paleocene and Early Eocene, with the appearance of most of the representatives of extant lineages. Basal Eocene marine fish diversity is currently ...
Turnbull Christine - - 2012
The social insect soldier is perhaps the most widely known caste, because it often exhibits spectacular weapons, such as highly enlarged jaws or reinforced appendages, which are used to defend the colony against enemies ranging in size from wasps to anteaters. We examined the function of the enlarged forelimbs of ...
Fugazzola M C - - 2012
The main aim of this study was to evaluate the relationship between the social hierarchy of plain zebra, Equus quagga, and the level of parasitism. For the study 141 fecal samples from the same number of animals were collected within the two major populations of E. quagga of Uganda (Lake ...
Iles William J D - - 2012
• Premise of the study: Species relationships are unknown in Hydatellaceae, a small family of dwarf aquatics related to water lilies that arose near the base of angiosperm phylogeny. Here we use molecular evidence to infer a species tree for the family and apply this to reconstructing major transitions in ...
M'gonigle Leithen K - - 2012
Empirical data indicate that sexual preferences are critical for maintaining species boundaries, yet theoretical work has suggested that, on their own, they can have only a minimal role in maintaining biodiversity. This is because long-term coexistence within overlapping ranges is thought to be unlikely in the absence of ecological differentiation. ...
Kobayashi Kazuya - - 2012
In certain planarian species that are able to switch between asexual and sexual reproduction, determining whether a sexual has the ability to switch to the asexual state is problematic, which renders the definition of sexuals controversial. We experimentally show the existence of two sexual races, acquired and innate, in the ...
Lambert Kelly G - - 2012
Few evolutionary transformations rival the complex neurobiological modifications accompanying the mammalian transition to parenthood. Research conducted primarily in maternal rodents highlights the engagement of multiple areas of the brain to initiate and maintain interest in resource-depleting vulnerable pups throughout lactation. Interestingly, many modifications marking the transition to motherhood result in ...
Valim Michel P - - 2012
Abstract A new chewing louse genus and species belonging to the family Philopteridae, namely, Palmaellus inexpectatus, is described. The new genus is distinguished from the other Ischnoceran genera hitherto described by its peculiar characters of the dorsal anterior head plate with two postero-lateral projections, pterothorax and abdomen with scarce chaetotaxy, ...
Zohdy Sarah - - 2012
ABSTRACT: BACKGROUND: Studies of host-parasite interactions have the potential to provide insights into the ecology of both organisms involved. We monitored the movement of sucking lice (Lemurpediculus verruculosus), parasites that require direct host-host contact to be transferred, in their host population of wild mouse lemurs (Microcebus rufus). These lemurs live ...
Fitzpatrick J L - - 2012
This review highlights the potential role that post-copulatory sexual selection plays in elasmobranch reproductive systems and the utility of this group to further understanding of evolutionary responses to the post-copulatory processes of sperm competition and cryptic female choice. The growing genetic evidence for female multiple mating (polyandry) in elasmobranchs is ...
Meager Justin J - - 2012
Much of the inter-individual variation observed in animal behaviour is now attributed to the existence of behavioural phenotypes or animal personalities. Such phenotypes may be fundamental to fisheries and aquaculture, yet there have been few detailed studies of this phenomenon in exploited marine animals. We investigated the behavioural and neuroendocrine ...
Arce A N - - 2012
Parents of many species care for their offspring by protecting them from a wide range of environmental hazards, including desiccation, food shortages, predators, competitors, and parasites and pathogens. Currently, little is known about the mechanisms and fitness consequences of parental defences against bacterial pathogens and competitors. Here, we combine approaches ...
Parejo D - - 2012
Many animals react to danger by producing chemical cues that can be smelled by others, which is called the smell of fear. Some bird species produce chemical compounds when threatened, such as nestlings of the Eurasian roller Coracias garrulus that vomit an odorous orange liquid when scared in their nests. ...
Ebensperger Luis A - - 2012
1. Understanding how variation in fitness relates to variation in group living remains critical to determine whether this major aspect of social behaviour is currently adaptive. 2. Available evidence in social mammals aimed to examine this issue remains controversial. Studies show positive (i.e. potentially adaptive), neutral or even negative fitness effects of ...
Lourenço Wilson R - - 2012
A new species of scorpion belonging to the family Pseudochactidae and the genus Vietbocap is described from the Tham Nam Lot cave, located in the Laotian part of the Khammouan-Ke Bang karst in Southeast Asia. Like the previously described species of the genus, Vietbocap lao sp. n. is a true ...
Dejean Alain - - 2012
Here we show that trying to rob prey (cleptobiosis) from a highly specialized predatory ant species is risky. To capture prey, Allomerus decemarticulatus workers build gallery-shaped traps on the stems of their associated myrmecophyte, Hirtella physophora. We wondered whether the frequent presence of immobilized prey on the trap attracted flying ...
McPherson F J - - 2012
Sexual dimorphisms (SDs) have evolved in mammals to assure greater reproductive success for individuals, usually males. Secondary sexual characteristics (SSC) developed to further this objective, tending to be more pronounced in species which are polygynous, diurnal and open-habitat dwellers. Sexual selection has underpinned many of these changes, which are not ...
Moyle Robert G - - 2012
The avian family Timaliidae is a species rich and morphologically diverse component of African and Asian tropical forests. The morphological diversity within the family has attracted interest from ecologists and evolutionary biologists, but systematists have long suspected that this diversity might also mislead taxonomy, and recent molecular phylogenetic work has ...
Ritchie Euan G - - 2012
Recent advances highlight the potential for predators to restore ecosystems and confer resilience against globally threatening processes, including climate change and biological invasions. However, releasing the ecological benefits of predators entails significant challenges. Here, we discuss the economic, environmental and social considerations affecting predator-driven ecological restoration programmes, and suggest approaches ...
Lukas Dieter - - 2012
Comparative studies of social insects and birds show that the evolution of cooperative and eusocial breeding systems has been confined to species where females mate completely or almost exclusively with a single male, indicating that high levels of average kinship between group members are necessary for the evolution of reproductive ...
Modlmeier Andreas P - - 2012
The fitness consequences of animal personalities (also known as behavioural syndromes) have recently been studied in several solitary species. However, the adaptive significance of collective personalities in social insects and especially of behavioural variation among group members remains largely unexplored. Although intracolonial behavioural variation is an important component of division ...
Vitousek Maren N - - 2012
A long term study of warblers in the Himalayas reveals a surprising contrast in the effects of warm springs as opposed to warm summers on a signaling trait, emphasizing the need to consider year-round influences of the environment on morphological variation.
Kotrschal Alexander - - 2012
Selection pressures that act differently on males and females produce numerous differences between the sexes in morphology and behaviour. However, apart from the controversial report that males have slightly heavier brains than females in humans, evidence for substantial sexual dimorphism in brain size is scarce. This apparent sexual uniformity is ...
Burger Joseph R - - 2012
Social animals are susceptible to high infection levels by contact-transmitted parasites due to increased conspecific interaction. Exotic parasites are known to have adverse consequences on native hosts. We examined the relationship between social group size and exotic ectoparasite loads, and adult infection levels with per capita fitness and offspring survival ...
Botero Carlos A - - 2012
Environmentally-induced fluctuation in the form and strength of natural selection can drive the evolution of morphology, physiology, and behavior. Here we test the idea that fluctuating climatic conditions may also influence the process of sexual selection by inducing unexpected reversals in the relative quality or sexual attractiveness of potential breeding ...
Lifjeld Jan T - - 2012
There is growing evidence that post-copulatory sexual selection, mediated by sperm competition, influences the evolution of sperm phenotypes. Evidence for pre-copulatory sexual selection effects on sperm traits, on the other hand, is rather scarce. A recent paper on the pied flycatcher, Ficedula hypoleuca, reported phenotypic associations between sperm length and ...
Li Chunlin - - 2012
Quantifying vigilance and exploring the underlying mechanisms has been the subject of numerous studies. Less attention has focused on the complex interplay between contributing factors such as reproductive status, social rank, sex and group size. Reproductive status and social rank are of particular interest due to their association with mating ...
Campomizzi Andrew J - - 2012
Determining where organisms breed and understanding why they breed in particular locations are fundamental biological questions with conservation implications. Breeding-site fidelity is common in migratory, territorial songbirds and is typically thought to occur following reproductive success with a social mate and success of nearby conspecifics. It is currently unknown if ...
Veltsos Paris - - 2012
Sexual selection has the potential to contribute to population divergence and speciation. Most studies of sexual selection in Drosophila have concentrated on a single signaling modality, usually either courtship song or cuticular hydrocarbons (CHCs), which can act as contact pheromones. We have examined the relationship between both signal types and ...
Budha Prem B - - 2012
A new genus and species of pseudosigmurethrous orthurethran pulmonate of the family Cerastidae, Darwininitium shiwalikianumgen. n. and sp. n. is described from the Lesser Himalaya of Nepal. It represents the first record of an orthurethran with a fully developed pseudosigmurethrous pallial system, having a completely closed secondary ureteric system. Biogeographically ...
Chouvenc Thomas - - 2012
Over the past 50 years, repeated attempts have been made to develop biological control technologies for use against economically important species of subterranean termites, focusing primarily on the use of the entomopathogenic fungus Metarhizium anisopliae. However, no successful field implementation of biological control has been reported. Most previous work has ...
Vander Wal E - - 2012
For animals living in natural or semi-natural settings, empirical data on how sociality changes in response to increasing population density are few, especially with respect to true conspecific density and not group size. However, insight into this line of research may be far-reaching--from understanding density dependence in sexual selection to ...
Desantis Larisa R G - - 2012
Climate change alters species distributions, causing plants and animals to move north or to higher elevations with current warming. Bioclimatic models predict species distributions based on extant realized niches and assume niche conservation. Here, we evaluate if proxies for niches (i.e., range areas) are conserved at the family level through ...
Webster Reginald P - - 2012
We report ten new species records for the Coleoptera fauna of New Brunswick, Canada from the families Dermestidae, Endecatomidae, Bostrichidae, and Ptinidae. Anthrenus fuscus Olivier and Anthrenus museorum (Linnaeus) of the family Dermestidae are newly recorded for New Brunswick. Endecatomus rugosus (Randall) and the family Endecatomidae are recorded for the ...
Purcell Jessica - - 2012
Species that differ in their social system, and thus in traits such as group size and dispersal timing, may differ in their use of resources along spatial, temporal, or dietary dimensions. The role of sociality in creating differences in habitat use is best explored by studying closely related species or ...
Nakayama Shinnosuke - - 2012
Studies of coordinated movement have found that, in many animal species, bolder individuals are more likely to initiate movement and shyer individuals to follow. Here, we show that in pairs of foraging stickleback fish, leadership is not merely a passive consequence of temperamental differences. Instead, the act of initiating a ...
Furness Andrew I - - 2012
Convergent evolution is characterized by the independent evolution of similar phenotypes within similar selective environments. Previous work on Trinidadian killifish, Rivulus hartii, demonstrated repeatable life-history differences across communities that differ in predation intensity. These studies were performed in rivers located on the south slope of Trinidad's Northern Range Mountains. There ...
Reback Cathy J - - 2011
This study compared outcomes in methamphetamine use and sexual risk behaviors from a modified gay-specific, cognitive behavioral therapy (GCBT) combined with a low-cost contingency management (CM; [GCBT+CM]) intervention to prior findings from clinical trials of the original GCBT. Effect sizes for primary outcomes were compared using meta analysis. Comparisons of ...
AdukauskienÄ— Dalia - - 2011
More than 5 million people are bitten by venomous snakes annually and more than 100 000 of them die. In Europe, one person dies due to envenomation every 3 years. There is only one venomous snake species in Lithuania - the common adder (Vipera berus) - which belongs to the ...
Baracchi David - - 2011
Sociality is associated with an increased risk of disease transmission and one of the first defense of the insect colonies is represented by antimicrobial secretions. In many eusocial hymenopteran species venom glands represent one of the most important source of antimicrobial substances. It is known that in highly eusocial species ...
Rosvall Kimberly A - - 2011
In spite of recent interest in sexual selection in females, debate exists over whether traits that influence female-female competition are sexually selected. This review uses female-female aggressive behavior as a model behavioral trait for understanding the evolutionary mechanisms promoting intrasexual competition, focusing especially on sexual selection. I employ a broad ...
Cothran Rickey D - - 2012
Sexual traits are especially sensitive to low food resources. Other environmental parameters (e.g., predation) should also affect sexual trait expression by favoring investment in viability traits rather than sexual traits. We know surprisingly little about how predators alter investment in sexual traits, or how predator and resource environments interact to ...
Sharma Manmohan D - - 2012
Natural and sexual selection are classically thought to oppose one another, and although there is evidence for this, direct experimental demonstrations of this antagonism are largely lacking. Here, we assessed the effects of sexual and natural selection on the evolution of cuticular hydrocarbons (CHCs), a character subject to both modes ...
Walsh Kate - - 2011
Despite data indicating that child maltreatment (CM) in various forms is associated with adult sexual victimization among community women, few studies have explicitly explored how types of CM might relate to prison sexual victimization. Because little is known about how CM might give rise to prison sexual victimization, the present ...
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