Search results for " evolution."
showing 10 items of 9653 documents
Crab spiders of the families Thomisidae and Philodromidae (Arachnida: Araneae) from Iran
2004
Spiders of the families Thomisidae and Philodromidae (Arachnida, Araneae) mainly collected in the mountainous areas of Iran in 1978 are taxonomically studied and classified into 21 species of 10 genera. Most species are illustrated and described on the basis of the present specimens. Except for only two species, Xysticus kulczynskii Wierzbicki 1902 and Synaema globosum (Fabricius 1775), already known from this country, 19 species are new records to the Iranian fauna. Of these, 14 species, Tmarus stellio Simon 1875, Xysticus ninnii Thorell 1872 (subsp. fusciventris Crome 1965), X. cristatus (Clerck 1758), X. kochi Thorell 1872, X. gallicus Simon 1875, Oxyptila nigrita Thorell 1875, Heriaeus …
Revisional Notes on Trictenotoma Gray, 1832 (Coleoptera: Trictenotomidae) in Indochina Bioregion, with Description of a New Species
2020
A review and species key to TrictenotomaGray, 1832 (Trictenotomidae Blanchard, 1845) from the Indochina bioregion, mainland Southeast Asia, is presented for the first time. Adults of Trictenotoma childreniGray, 1832, T. davidi Deyrolle, 1875 and T. mouhoti Deyrolle, 1875 are redescribed. Trictenotoma pollockisp. nov. from southern Vietnam is described and illustrated. A lectotype is designated for T. mouhoti Deyrolle, 1875.
BOTH MALE AND FEMALE SEXUAL ORNAMENTS REFLECT OFFSPRING PERFORMANCE IN A FISH
2010
Secondary sexual characters are often expressed in both sexes (mutual ornamentation), but are less often studied simultaneously. We studied the adaptive signaling function of male and female ornamentation in a mutually ornamented fish, the whitefish Coregonus lavaretus. In an experimental design in which nongenetic environmental effects were minimized, we found that highly ornamented females, males, and their parental combinations had offspring with better swimming performance and predator-avoidance ability than less ornamented individuals or combinations. Furthermore, highly ornamented females had larger offspring that also had higher yolk volume than less ornamented individuals. Offspring…
Muscular Strength Imbalances Are not Associated with Skin Temperature Asymmetries in Soccer Players
2020
Although strength imbalances using isokinetic dynamometer have been examined for injury risk screening in soccer players, it is very expensive and time-consuming, making the evaluation of new methods appealing. The aim of the study was to analyze the agreement between muscular strength imbalances and skin temperature bilateral asymmetries as well as skin temperature differences in the hamstrings and quadriceps. The skin temperature of the anterior and posterior thigh of 59 healthy male soccer athletes was assessed at baseline using infrared thermography for the identification of hamstrings-quadriceps skin temperature differences and thermal asymmetries (>
Projecting biodiversity and wood production in future forest landscapes: 15 key modeling considerations
2017
A variety of modeling approaches can be used to project the future development of forest systems, and help to assess the implications of different management alternatives for biodiversity and ecosystem services. This diversity of approaches does however present both an opportunity and an obstacle for those trying to decide which modeling technique to apply, and interpreting the management implications of model output. Furthermore, the breadth of issues relevant to addressing key questions related to forest ecology, conservation biology, silviculture, economics, requires insights stemming from a number of distinct scientific disciplines. As forest planners, conservation ecologists, ecologica…
Building on 150 Years of Knowledge : The Freshwater Isopod Asellus aquaticus as an Integrative Eco-Evolutionary Model System
2021
Interactions between organisms and their environments are central to how biological diversity arises and how natural populations and ecosystems respond to environmental change. These interactions involve processes by which phenotypes are affected by or respond to external conditions (e.g., via phenotypic plasticity or natural selection) as well as processes by which organisms reciprocally interact with the environment (e.g., via eco-evolutionary feedbacks). Organism-environment interactions can be highly dynamic and operate on different hierarchical levels, from genes and phenotypes to populations, communities, and ecosystems. Therefore, the study of organism-environment interactions requir…
Effects of anthropogenic stress on hosts and their microbiomes: Treated wastewater alters performance and gut microbiome of a key detritivore ( Asell…
2023
Human activity is a major driver of ecological and evolutionary change in wild populations and can have diverse effects on eukaryotic organisms as well as on environmental and host-associated microbial communities. Although host-microbiome interactions can be a major determinant of host fitness, few studies consider the joint responses of hosts and their microbiomes to anthropogenic changes. In freshwater ecosystems, wastewater is a widespread anthropogenic stressor that represents a multifarious environmental perturbation. Here, we experimentally tested the impact of treated wastewater on a keystone host (the freshwater isopod Asellus aquaticus) and its gut microbiome. We used a semi-natur…
Eutrophication reduces the nutritional value of phytoplankton in boreal lakes
2019
Eutrophication (as an increase in total phosphorus [TP]) increases harmful algal blooms and reduces the proportion of high-quality phytoplankton in seston and the content of ω-3 long-chain polyunsaturated fatty acids (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) in fish. However, it is not well-known how eutrophication affects the overall nutritional value of phytoplankton. Therefore, we studied the impact of eutrophication on the production (as concentration; μg L−1) and content (μg mg C−1) of amino acids, EPA, DHA, and sterols, i.e., the nutritional value of phytoplankton in 107 boreal lakes. The lakes were categorized in seven TP concentration categories ranging from ultra…
Temporal genetic structure in a poecilogonous polychaete: the interplay of developmental mode and environmental stochasticity
2014
Background: Temporal variation in the genetic structure of populations can be caused by multiple factors, including natural selection, stochastic environmental variation, migration, or genetic drift. In benthic marine species, the developmental mode of larvae may indicate a possibility for temporal genetic variation: species with dispersive planktonic larvae are expected to be more likely to show temporal genetic variation than species with benthic or brooded non-dispersive larvae, due to differences in larval mortality and dispersal ability. We examined temporal genetic structure in populations of Pygospio elegans, a poecilogonous polychaete with within-species variation in developmental m…
Spatial and temporal pattern of neuroblasts, proliferation, and Engrailed expression during early brain development in Tenebrio molitor L. (Coleopter…
2003
Abstract In insects, the knowledge of embryonic brain development is still fragmentary, and comparative data are scarce. In this study, we explored aspects of embryonic brain development in the coleopteran Tenebrio molitor . A detailed description is provided of the spatial and temporal pattern of the embryonic brain neuroblasts during 18–60% of embryonic development. Approximately 125 brain NBs have been identified in each hemisphere of the brain at about 40% of embryonic development. A subset of five neuroblasts, among them the two progenitors of the mushroom bodies and two progenitors of the larval antennal lobe, are morphologically identifiable by their larger size. As revealed by incor…