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1. Mating patterns of Gammarus lacustris (Amphipoda: Gammaridae) from three populations across a gradient on the Tibetan Plateau

Author:
Yu, T. L.; Chen, J. B.
Source:
The Italian journal of zoology 2013 v.80 no.4 pp. 608-613
ISSN:
1748-5851
Subject:
Gammarus; body size; dimorphism; fecundity; females; males; microhabitats; population; random mating; sexual selection; zoology; China
Abstract:
... The large-male mating advantage and size-assortative mating are two different size-based patterns which deviate from random mating in Gammarus species. The size-assortative pairing in gammarid amphipods may have arisen for microhabitat segregation, loading constraints, sexual selection, or a combination of them. This study investigated the mating patterns of Gammarus lacustris from three populatio ...
DOI:
10.1080/11250003.2013.849295

2. Sexual size dimorphism in anurans fails to obey Rensch’s rule

Author:
Liao, Wen Bo; Zeng, Yu; Zhou, Cai Quan; Jehle, Robert
Source:
Frontiers in zoology 2013 v.10 no.1 pp. 10
ISSN:
1742-9994
Subject:
Anura; body size; data collection; dimorphism; females; life history; males; phylogeny
Abstract:
... BACKGROUND: Sexual size dimorphism (SSD) is related to ecology, behaviour and life history of organisms. Rensch’s rule states that SSD increases with overall body size in species where males are the larger sex, while decreasing with body size when females are larger. To test this rule, we analysed literature as well as own data on male and female body size in anurans (39 species and 17 genera). We ...
DOI:
10.1186/1742-9994-10-10
PubMed:
23496925
PubMed Central:
PMC3599542

3. Leptin, vitamin D, and cardiorespiratory fitness as risk factors for insulin resistance in European adolescents: gender differences in the HELENA Study

Author:
Jiménez-Pavón, David; Sesé, María A.; Valtueña, Jara; Cuenca-García, Magdalena; González-Gross, Marcela; Gottrand, Frederic; Kafatos, Anthony; Manios, Yannis; Widhalm, Kurt; de Henauw, Stefaan; Polito, Angela; Pérez-López, Faustino R.; Moreno, Luis A.
Source:
Applied Physiology, Nutrition, and Metabolism 2013 v.39 no.5 pp. 530-537
ISSN:
1715-5320
Subject:
C-reactive protein; adolescence; adolescents; covariance; cross-sectional studies; dietary fat; dimorphism; energy intake; fat body; females; gender differences; homeostasis; insulin resistance; leptin; lifestyle; males; metabolism; odds ratio; physical activity; questionnaires; randomized clinical trials; regression analysis; risk factors; socioeconomic status; vitamin D; Europe
Abstract:
... The purpose of this study was to identify the relevance of a set of risk factors for insulin resistance in adolescents from Europe and to consider their possible gender-specific associations. The Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study (HELENA-CSS) was conducted in 1053 European adolescents (mean age, 14.9 years) in a school setting in 9 countries. Three anthr ...
DOI:
10.1139/apnm-2013-0250

4. Body size and shape variation in Ground Beetle Carabus aeruginosus F.-W., 1822 (Coleoptera, Carabidae)

Author:
Sukhodolskaya, R. A.; Eremeeva, N. I.
Source:
Contemporary problems of ecology 2013 v.6 no.6 pp. 609-615
ISSN:
1995-4255
Subject:
Carabidae; biotopes; body size; dimorphism; environmental factors; females; linear models; males; meadows; morphometry; statistics
Abstract:
... Morphometric variation in Ground Beetle Carabus aeruginosus F.-W. was studied. Beetles were sampled in different habitats in the gradient of disturbance: Kemerovo city, its suburbs and natural biotopes outside the city. We used multidimensional statistics (linear models, PCA and MDS) to show that all environmental factors (anthropogenic press, biotope vegetation) contributed significantly into the ...
DOI:
10.1134/S1995425513060127

5. Bone histology as an approach to providing data on certain key life history traits in mammals: Implications for conservation biology

Author:
Marín-Moratalla, Nekane; Jordana, Xavier; Köhler, Meike
Source:
Mammalian biology = 2013 v.78 no.6 pp. 422-429
ISSN:
1616-5047
Subject:
Addax nasomaculatus; adults; antelopes; bones; case studies; data collection; death; dimorphism; females; growth rings; health status; histology; issues and policy; longevity; males; models; population; reproduction; risk assessment; sexual maturity; wildlife management; zoos
Abstract:
... The knowledge of the life histories of wild mammals is of crucial importance in the field of conservation management. The endangered status of many species calls for faster data collection that can be used in risk assessment and, ultimately, for designing conservation policies. This study is pioneering the potential of bone histology to provide data on life history traits crucial for conservation ...
DOI:
10.1016/j.mambio.2013.07.079

6. Foraging segregation in tropical and polar seabirds: Testing the Intersexual Competition Hypothesis

Author:
Mancini, Patrícia L.; Bond, Alexander L.; Hobson, Keith A.; Duarte, Leandro S.; Bugoni, Leandro
Source:
Journal of experimental marine biology and ecology 2013 v.449 pp. 186-193
ISSN:
0022-0981
Subject:
blood; breeding; breeding season; breeding sites; diet; dimorphism; females; foraging; males; muscles; niches; phylogeny; seabirds; stable isotopes
Abstract:
... The Intersexual Competition Hypothesis (ICH) predicts that sexual size dimorphism (SSD) in seabirds may reduce intraspecific food competition through the exploitation of different trophic niches by each sex. We tested the ICH using stable isotopes (δ15N and δ13C) from whole blood and muscle from six tropical and five polar seabird species sampled at breeding sites. We expected that greater morphol ...
DOI:
10.1016/j.jembe.2013.09.011

7. Male–male contests for mates, sexual size dimorphism, and sex ratio in a natural population of a solitary parasitoid

Author:
Macedo, Margarete V.; Monteiro, Ricardo F.; Silveira, Mariana P.; Mayhew, Peter J.
Source:
Behavioural processes 2013 v.100 pp. 1-8
ISSN:
0376-6357
Subject:
Eurytoma; body size; dimorphism; females; life history; males; parasitoids; sex allocation; sex ratio; variance
Abstract:
... Understanding how different behavioural and life history traits interact is fundamental to developing ethological theory. Here we study the interaction of male–male competition for mates and sexual size dimorphism in a solitary wasp, with implications for sex allocation. In Hymenoptera, females are normally larger than males suggesting that males do not benefit as much as females from larger size. ...
DOI:
10.1016/j.beproc.2013.07.003

8. Sex Determination and Sexual Size Dimorphism in the Red-billed Tropicbird (Phaethon aethereus) and White-tailed Tropicbird (P. lepturus)

Author:
Nunes, Guilherme Tavares; Leal, Gustavo Da Rosa; Campolina, Cynthia; Freitas, Thales Renato Ochotorena De; Efe, Márcio Amorim; Bugoni, Leandro
Source:
Waterbirds 2013 v.36 no.3 pp. 348-352
ISSN:
1524-4695
Subject:
blood; coasts; dimorphism; females; linear models; males; morphometry; seabirds; sex determination; Atlantic Ocean; Brazil
Abstract:
... Tropicbirds (order Phaethontiformes) are a well-studied seabird taxon, but there have been no published studies on sexual size dimorphism. Here, we investigated sexual size dimorphism in the Red-billed Tropicbird (Phaethon aethereus) and the White-tailed Tropicbird (P. lepturus), and evaluated the applicability of using morphometrics and discriminant functions to sex birds in the field. We sampled ...
DOI:
10.1675/063.036.0312

9. Oligomerization and other evolutionary changes in the antennae of tetrastichine wasps (Hymenoptera, Eulophidae)

Author:
Kosheleva, O. V.
Source:
Entomological revue 2013 v.93 no.6 pp. 725-736
ISSN:
0013-8738
Subject:
Eulophidae; antennae; dimorphism; evolution; females; males
Abstract:
... The following trends in oligomerization of the male and female antennae in Tetrastichinae were determined. (1) Reduction (shortening) of the basal segment of the funicle. (2) Reduction (shortening) of the middle segments of the funicle (not recorded in chalcids before). (3) Loss of homonomy by the funicle. (4) Fusion of the claval segments. (5) Reduction (shortening) of the apical claval segment. ...
DOI:
10.1134/S0013873813060067

10. Sexually dimorphic myofilament function and cardiac troponin I phosphospecies distribution in hypertrophic cardiomyopathy mice

Author:
McKee, Laurel A.K.; Chen, Hao; Regan, Jessica A.; Behunin, Samantha M.; Walker, Jeffery W.; Walker, John S.; Konhilas, John P.
Source:
Archives of biochemistry and biophysics 2013 v.535 no.1 pp. 39-48
ISSN:
0003-9861
Subject:
Ca2-transporting ATPase; adenosinetriphosphatase; calcium; cardiomyopathy; dimorphism; females; males; mice; mutants; myosin heavy chains; phosphorylation; polyacrylamide gel electrophoresis; post-translational modification; troponin I; troponin T
Abstract:
... The pathological progression of hypertrophic cardiomyopathy (HCM) is sexually dimorphic such that male HCM mice develop phenotypic indicators of cardiac disease well before female HCM mice. Here, we hypothesized that alterations in myofilament function underlies, in part, this sex dimorphism in HCM disease development. Firstly, 10–12month female HCM (harboring a mutant [R403Q] myosin heavy chain) ...
DOI:
10.1016/j.abb.2012.12.023
PubMed:
23352598
PubMed Central:
PMC3640654

11. Diet and reproductive biology of the Starred Agama, Laudakia stellio (Linnaeus, 1758) (Squamata: Agamidae), in the northern Sinai, Egypt

Author:
Ibrahim, Adel A.; El-Naggar, Moustafa H.
Source:
Zoology in the Middle East 2013 v.59 no.2 pp. 136-143
ISSN:
2326-2680
Subject:
Coleoptera; clutch size; diet; dimorphism; eggs; females; head; insects; males; sexual maturity; Egypt
Abstract:
... We quantified sexual size dimorphism, diet and reproduction in the Starred Agama, Laudakia stellio , in northern Sinai. Males were larger than females in snout-vent length and head index. The species is a sit-and-wait predator and feeds on insects, mainly coleopterans. About 30% of stomachs included plant material. No difference between sexes existed in terms of prey size preference. The reproduct ...
DOI:
10.1080/09397140.2013.810875

12. Evolution of mating systems and sexual size dimorphism in North American cyprinids

Author:
Pyron, M.; Pitcher, T. E.; Jacquemin, S. J.
Source:
Behavioral ecology and sociobiology 2013 v.67 no.5 pp. 747-756
ISSN:
0340-5443
Subject:
Cyprinidae; body size; dimorphism; females; fish; males; mating systems; models; phylogeny; spawning; sperm competition; testes
Abstract:
... Mating systems evolve with sexual size dimorphism (SSD) in many animals. Mating systems with males larger than females occur when males compete for female access or guard territories, while mating systems with group mating tend to occur in species where females are the same size or larger than males. In addition to variation in SSD with mating system, sperm competition varies among mating systems ...
DOI:
10.1007/s00265-013-1498-5

13. Size-biased allocation of prey from male to offspring via female: family conflicts, prey selection, and evolution of sexual size dimorphism in raptors

Author:
Sonerud, Geir A.; Steen, Ronny; Løw, Line M.; Røed, Line T.; Skar, Kristin; Selås, Vidar; Slagsvold, Tore
Source:
Oecologia 2013 v.172 no.1 pp. 93-107
ISSN:
0029-8549
Subject:
Falco; birds of prey; dimorphism; evolution; females; food safety; foods; lizards; males; nests; progeny; small mammals
Abstract:
... In birds with bi-parental care, the provisioning link between prey capture and delivery to dependent offspring is regarded as often symmetric between the mates. However, in raptors, the larger female usually broods and feeds the nestlings, while the smaller male provides food for the family, assisted by the female in the latter part of the nestling period, if at all. Prey items are relatively larg ...
DOI:
10.1007/s00442-012-2491-9
PubMed:
23073637

14. Sex-specific vulnerability to breeding conditions in chicks of the sexually monomorphic Gull-billed Tern

Author:
Villegas, Auxiliadora; Masero, José A.; Corbacho, Casimiro; Gutiérrez, Jorge S.; Albano, Noelia; Sánchez-Guzmán, Juan M.
Source:
Journal of ornithology 2013 v.154 no.2 pp. 431-439
ISSN:
2193-7192
Subject:
dimorphism; nutritional status; rearing; males; breeding; early development; metabolites; phenology; environmental factors; sex ratio; progeny; chicks; clutch size; females; nestlings
Abstract:
... Environmental conditions during early development may differentially affect male and female offspring, and the effects of this sex–environment interaction in chick performance may be exaggerated under harsh conditions. In birds, most of the currently available evidence on sex-biased environmental sensitivity in nestlings is derived from species that display sexual size dimorphism, while studies on ...
DOI:
10.1007/s10336-012-0907-2

15. Reproduction, growth, and defense trade-offs vary with gender and reproductive allocation in Ilex glabra (Aquifoliaceae)

Author:
Buckley, Nicholas E.; Avila-Sakar, Germán
Source:
American journal of botany 2013 v.100 no.2 pp. 357-364
ISSN:
0002-9122
Subject:
Ilex glabra; defoliation; dimorphism; females; flowering; herbivores; leaves; males; phenology; prediction; reproductive performance; resource allocation; Nova Scotia
Abstract:
... • Premise of the study: Male-biased herbivory in dioecious species is expected as a consequence of selection for increased resistance (reduced attack) in the sex with higher reproductive costs—females. Empirical support of this prediction is taxonomically restricted and fraught with exceptions. Phenological changes in resource allocation to reproduction may change the trade-offs among functions in ...
DOI:
10.3732/ajb.1200603
PubMed:
23328690

16. Sexual segregation in red deer: is social behaviour more important than habitat preferences?

Author:
Alves, Joana; Alves da Silva, António; Soares, Amadeu M.V.M.; Fonseca, Carlos
Source:
Animal behaviour 2013 v.85 no.2 pp. 501-509
ISSN:
0003-3472
Subject:
Cervus elaphus; adults; age structure; animal behavior; autumn; body size; dimorphism; females; food availability; habitat preferences; habitats; males; peers; social behavior; vertebrates
Abstract:
... Sexual segregation among vertebrates is a common phenomenon, usually assumed to be associated with sexual body size dimorphism and explained by differences in habitat use or social behaviours. Various hypotheses explain sexual segregation in terms of social or habitat factors. The factors controlling sexual segregation are as yet unclear and the hypotheses put forward to explain it have generated ...
DOI:
10.1016/j.anbehav.2012.12.018

17. Sexual size dimorphism in the ontogeny of the solitary predatory wasp Symmorphus allobrogus (Hymenoptera: Vespidae)

Author:
Budrienė, Anna; Budrys, Eduardas; Nevronytė, Žaneta
Source:
Comptes rendus 2013 v.336 no.2 pp. 57-64
ISSN:
1631-0691
Subject:
Vespidae; dimorphism; ecology; eggs; females; larvae; larval development; males; ontogeny
Abstract:
... Sex-specific patterns of individual growth, resulting in sexual size dimorphism (SSD), are a little studied aspect of the ontogeny related to the evolutionary history and affected by the ecology of a species. We used empirical data on the development of the predatory wasp Symmorphus allobrogus (Hymenoptera, Vespidae) to test the hypotheses that sexual differences of growth resulting in the female- ...
DOI:
10.1016/j.crvi.2013.03.001

18. Cloning and characterization of an mRNA encoding an insulin receptor from the horned scarab beetle Onthophagus nigriventris (Coleoptera: Scarabaeidae)

Author:
Corley Lavine, Laura; Hahn, Laura L.; Warren, Ian A.; Garczynski, Stephen F.; Dworkin, Ian; Emlen, Douglas J.
Source:
Archives of insect biochemistry and physiology 2013 v.82 no.1 pp. 43
ISSN:
1520-6327
Subject:
Onthophagus; amino acids; body length; dimorphism; dung beetles; environmental factors; females; gene expression; growth traits; hormone receptors; horns; insulin; males; messenger RNA; molecular cloning; morphs; nucleotide sequences; nutrition; peptides; proteins; species diversity
Abstract:
... The insulin signaling pathway is the primary signaling pathway coupling growth with nutritional condition in all animals. Sensitivity to circulating levels of insulin has been shown to regulate the growth of specific traits in a dose-dependent manner in response to environmental conditions in a diversity of insect species. Alternative phenotypes in insects manifest in a variety of morphologies suc ...
Handle:
10113/55824
DOI:
10.1002/arch.21072
PubMed:
23136112

19. Effects of selection for behavior, human approach mode and sex on vocalization in silver fox

Author:
Gogoleva, Svetlana S.; Volodin, Ilya A.; Volodina, Elena V.; Kharlamova, Anastasia V.; Trut, Lyudmila N.
Source:
Journal of ethology 2013 v.31 no.1 pp. 95-100
ISSN:
0289-0771
Subject:
Vulpes vulpes; dimorphism; females; foxes; humans; males; vocalization
Abstract:
... This study presents a first direct comparison of vocal type, call rate and time spent vocalizing among Unselected, Tame and Aggressive strains of silver fox (Vulpes vulpes) in three modes of human approach (Provoking, Approach–Retreat, and Static). Also, it provides a first comparison of male and female vocal output in the Provoking test. Vocal types were found strain-specific irrespective of the ...
DOI:
10.1007/s10164-012-0353-x
PubMed:
23525128
PubMed Central:
PMC3601802

20. Sexual segregation in rockhopper penguins during incubation

Author:
Ludynia, Katrin; Dehnhard, Nina; Poisbleau, Maud; Demongin, Laurent; Masello, Juan F.; Voigt, Christian C.; Quillfeldt, Petra
Source:
Animal behaviour 2013 v.85 no.1 pp. 255-267
ISSN:
0003-3472
Subject:
Eudyptes; animal behavior; breeding; chicks; coastal water; dimorphism; environmental factors; fasting; females; forage; foraging; gender differences; global positioning systems; habitats; males; models; penguins; stable isotopes; surface water temperature; trophic relationships
Abstract:
... Many animals show sex differences in foraging behaviour, which can be related to sex-specific size dimorphism, avoidance of intersexual competition for depletable resources or different energetic requirements of males and females. In southern rockhopper penguins, Eudyptes chrysocome, both sexes differ in their roles during breeding, which leads to differences in their energetic requirements. We th ...
DOI:
10.1016/j.anbehav.2012.11.001

21. Comparative morphology, biology and histology of reproductive development in three lines of Manihot esculenta Crantz (Euphorbiaceae: Crotonoideae)

Author:
Perera, P. I. P.; Quintero, M.; Dedicova, B.; Kularatne, J. D. J. S.; Ceballos, H.
Source:
AoB plants 2013 v.5 no.0 pp. pls046
Subject:
Manihot esculenta; cassava; dimorphism; females; flowering; gametophytes; histology; males; phenology; pollen; viability
Abstract:
... Cassava flowering with emphasis on flowering pattern, morphology and phenology; pollen biology on viability and dimorphism, and histology on male and female gametophyte development are demonstrated. Reduced pollen viability at anthesis and the existence of pollen tri-morphism are the key findings. ...
DOI:
10.1093/aobpla/pls046
PubMed:
23346343
PubMed Central:
PMC3551401

22. Righting time versus shell size and shape dimorphism in adult Hermann’s tortoises: Field observations meet theoretical predictions

Author:
Stojadinović, Dragana; Milošević, Ðurađ; Crnobrnja-Isailović, Jelka
ISSN:
1570-7555
Subject:
Testudo hermanni; adults; ambient temperature; dimorphism; energy balance; females; geometry; males; prediction; theoretical models; tortoises
Abstract:
... We investigated the relation between righting time (RT) and carapace morphology in 303 adult Hermann’s tortoises (Testudo hermanni Gmelin, 1789) from two geographically close localities. Their size, shape and body mass, adjusted for size, were significantly different between males and females. Righting time differed among the populations and was related to the ambient temperature and the relative ...
DOI:
10.1163/15707563-00002420