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sexual dimorphism, etc ; ecology; meta-analysis; progeny; Show all 4 Subjects
Abstract:
... Inbreeding depression, the reduced fitness of the offspring of related individuals, can affect males and females differently. Although a comprehensive theoretical framework describing the causes of sex‐specific inbreeding depression is lacking, empirical evidence suggests that often one sex tends to be more vulnerable than the other. However, the generality, direction, and degree of sex‐specific d ...
dimorphism, etc ; Cerapachys; body size; evolution; polygyny; Thailand; Show all 6 Subjects
Abstract:
... The ant subfamily Dorylinae consists of the true army ants and non-army ant genera. The biology of these non-army ants is important in discussing the evolution of the army ant adaptive syndrome. We report on the colony composition, morphological characteristics, and phasic reproduction of a non-army doryline ant Cerapachys sulcinodis species complex collected in northern Thailand. Colony size was ...
dimorphism, etc ; Gerbillinae; allometry; geometry; monophyly; morphometry; skeleton; skull; synapomorphy; teeth; Show all 10 Subjects
Abstract:
... Molecular phylogenies support the monophyly of Desmodilliscus braueri and Pachyuromys duprasi as a clade basally split from all other gerbillines. While this monophyly supports their placement in a single tribe (Desmodilliscini), no morphological synapomorphies exist among desmodilliscines. This study compares the scale-independent cranial shapes of these two species using geometric morphometrics ...
sexual dimorphism, etc ; Drosophila; females; longevity; males; phylogeny; sexual selection; variance; Show all 8 Subjects
Abstract:
... Female promiscuity is a pervasive selective force on male reproductive traits, and the strength of sexual selection is predicted to influence the trade‐off between lifespan and reproduction. In species where sexual selection is intense, males are predicted to invest in sexual strategies that shorten their lifespan, potentially resulting in female‐biased sexual dimorphism in longevity. However, com ...
dimorphism, etc ; Paramecium; Tetrahymena; germ cells; microbiology; phenotypic plasticity; transcription (genetics); Show all 7 Subjects
Abstract:
... Ciliates have an extraordinary genetic system in which each cell harbors two distinct kinds of nucleus, a transcriptionally active somatic nucleus and a quiescent germline nucleus. The latter undergoes classical, heritable genetic adaptation, while adaptation of the somatic nucleus is only short-term and thus disposable. The ecological and evolutionary relevance of this nuclear dimorphism have nev ...
sexual dimorphism, etc ; Araneidae; females; males; phylogeny; spiders; taxonomy; China; Taiwan; Show all 9 Subjects
Abstract:
... Cyphalonotus is a poorly studied Old World araneid spider genus of which the phylogenetic proximity remains unknown due to the paucity of morphological and molecular data. We test the phylogenetic placement and the taxonomic composition of Cyphalonotus and place the male and female size variation of Cyphalonotus and related genera in an evolutionary context. Our collection and field observations f ...
sexual dimorphism, etc ; animal behavior; evolution; females; lekking; males; neck; peafowl; plumage; Show all 9 Subjects
Abstract:
... Males often exhibit elaborate ornamentation that contributes to their fitness. Similarly, females can also exhibit elaborate ornamentation, but we have a relatively limited understanding of its function. Recent studies have demonstrated that female ornamentation can function in both intrasexual competition and male mate choice, but few studies have been conducted on lekking species. We therefore i ...
sexual dimorphism, etc ; Japan; Philippines; Rhizostomeae; invertebrates; nematocysts; new species; species richness; Show all 8 Subjects
Abstract:
... Morphological variability within Cassiopea is well documented and has led to inaccuracies in the establishment of species boundaries in this taxon. Cassiopea medusae specimens from the Western Pacific (Japan and the Philippines) were analysed using multiple lines of complementary evidence, including types of cnidae, macro-morphology and molecular data. These observations lead to the recognition of ...
sexual dimorphism, etc ; Leiocassis; aquaculture; catfish; gynogenesis; males; sex determination; spermatozoa; China; Show all 9 Subjects
Abstract:
... Longsnout catfish (Leiocassis longirostris), an important commercial fish in China, shows significant sexual size dimorphism. However, the sex determination system and mechanism of longsnout catfish remain unknown. In this study, an effective protocol of artificial gynogenesis using heterologous sperm was successfully developed and male heterogametic XX/XY sex determination system was revealed in ...
sexual dimorphism, etc ; Actinopterygii; Elasmobranchii; fish; longevity; marine science; Indian Ocean; Reunion; Show all 8 Subjects
Abstract:
... Body length–weight (L–W) relationships of 123 fish species (122 Actinopterygii and 1 Elasmobranchii) were studied from 10 218 individuals caught around Réunion Island from 2000 to 2021. All species, except for 4 with a very small number of individuals and limited length range, showed a significant relationship between total length and total weight. For 52 species, the data showed the body becoming ...
sexual dimorphism, etc ; Drosophila; acclimation; energy; females; homeostasis; insects; lipids; metabolism; metabolites; starvation; Show all 11 Subjects
Abstract:
... The wild populations of Drosophila show highly adaptive body metabolism in response to changing environments. The traits associated with starvation and desiccation stress vary with the geographical locations as well as climatic conditions. The energy storage and utilization during these stresses varies among different species. We examined the effects of physiological stress i.e., desiccation and s ...
sexual dimorphism, etc ; Haliotis diversicolor; abalone; aquaculture; genomics; males; sex determination; shellfish; Taiwan; Show all 9 Subjects
Abstract:
... Small abalone (Haliotis diversicolor) is an economically important shellfish in aquaculture, yet its sex determination mechanism remains unclear. Based on the re-sequencing data, candidate sexually dimorphic loci, including 281 SNPs and 21 InDels, were screened out in small abalone. The candidate sexually dimorphic SNPs were located on thirteen chromosomes but mainly on Chr. 3 (43.4%) and Chr. 9 ( ...
sexual dimorphism, etc ; animal behavior; copulation; evolution; females; food availability; insects; males; progeny; Show all 9 Subjects
Abstract:
... Insect cuticular hydrocarbons provide desiccation resistance but may also be used in chemical signalling. Sexually dimorphic hydrocarbon blends, which may be transferred between individuals during copulation, are used especially in mate assessment. However, not all insect species produce sex-specific hydrocarbon blends, and their general utility in mate choice requires study of a broader range of ...
Ezequiel B. Nascimento; Aline Lima Dierschnabel; Ramón Hypolito Lima; Maria Bernadete C. Sousa; Deborah Suchecki; Regina H. Silva; Alessandra M. Ribeiro
sexual dimorphism, etc ; anxiety; cognition; corticosterone; fearfulness; females; locomotion; males; risk assessment; secretion; Show all 10 Subjects
Abstract:
... Stress encompasses reactions to stimuli that promote negative and positive effects on cognitive functions, such as learning and memory processes. Herein, we investigate the effect of restraint stress on learning, memory, anxiety levels and locomotor activity of male and female mice. We used the plus-maze discriminative avoidance task (PMDAT), a behavioral task based on the innate exploratory respo ...
sexual dimorphism, etc ; Vulpes vulpes; adults; computed tomography; geography; models; morphometry; orthopedics; wild animals; Show all 9 Subjects
Abstract:
... Three‐dimensional (3D) reconstructive techniques are being used in many morphometric studies and clinical applications. The red fox is a wild animal localized in a wide geography. This study has been performed to determine morphometric properties of the pelvic cavity and reveal differences between sexes via 3D reconstruction obtained by multi‐detector computed tomography images (MDCT) of the red f ...
sexual dimorphism, etc ; Uroteuthis; coasts; cryptic species; genes; mitochondria; monophyly; paraphyly; squid; Indian Ocean; Show all 10 Subjects
Abstract:
... The phylogenetic relationships of inshore squid species in the family Loliginidae is still ambiguous owing to the lack of morphological and molecular data. In the present study, the taxonomic status of squid species Uroteuthis duvaucelii (Orbigny, 1848), Uroteuthis edulis (Hoyle, 1885), Uroteuthis singhalensis (Ortmann, 1891) and Loliolus hardwickei (Gray, 1849) from the Indian coast was elucidate ...
sexual dimorphism, etc ; Elephas maximus; adults; body weight; data collection; death; evolutionary biology; prediction; Show all 8 Subjects
Abstract:
... In species with marked sexual dimorphism, the classic prediction is that the sex which undergoes stronger intrasexual competition ages earlier or quicker. However, more recently, alternative hypotheses have been put forward, showing that this association can be disrupted. Here, we utilize a unique, longitudinal data set of a semi‐captive population of Asian elephants (Elephas maximus), a species w ...
dimorphism, etc ; Cynoglossus semilaevis; aquaculture; body weight; females; genetic variation; growth performance; heritability; juveniles; phenotype; Show all 10 Subjects
Abstract:
... Tongue sole is an economically important marine flatfish with significant sexual growth dimorphism that female with superior growth performance, and phenotypic female proportion (FP) is rather low (10%–30%) under rearing conditions. Knowledge of whether genetic variation exists for FP is needed for determining the feasibility of including this desirable trait into breeding goal in tongue sole. The ...
sexual dimorphism, etc ; Potamopyrgus antipodarum; Trematoda; byproducts; castration; juveniles; larvae; natural selection; parasites; phenotype; snails; Show all 11 Subjects
Abstract:
... Natural selection should favour parasite genotypes that manipulate hosts in ways that enhance parasite fitness. However, it is also possible that the effects of infection are not adaptive. Here we experimentally examined the phenotypic effects of infection in a snail–trematode system. These trematodes (Atriophallophorus winterbourni) produce larval cysts within the snail's shell (Potamopyrgus anti ...
sexual dimorphism, etc ; Poecilia reticulata; body size; color; fish; freshwater; hybrids; males; personality; research; variance; Show all 11 Subjects
Abstract:
... The concept of animal personality is based on consistent individual differences in behaviour, yet little is known about the factors responsible for such variation. Theory based on sex-specific selection predicts sexual dimorphism in personality-related traits and, in some cases, differences in trait variances between the sexes. In this study, we examined the sources of individual variation for bol ...