Search results for "SEXUAL DIMORPHISM"
showing 10 items of 154 documents
Surface electromyographic evaluation of jaw muscles in children with unilateral crossbite and lateral shift in the early mixed dentition. Sexual dimo…
2011
Objectives: To examine the activity of jaw muscles at rest and during maximal voluntary clenching (MVC) in children with unilateral posterior crossbite (UPXB) and functional lateral shift in the early mixed dentition and to evaluate sex differences. Material and Methods: The sample included 30 children (15 males, 15 females) aged 6 to 10 years old, with UPXB and functional mandibular lateral shift (≥1.5 mm) in the early mixed dentition. sEMG activity coming from the muscle areas (anterior temporalis [AT], posterior temporalis [PT], masseter [MA] and suprahyoid [SH]) were obtained from both the crossbite (XB) and noncrossbite (NONXB) sides at mandibular rest position. sEMG acti-vity of the b…
The molecular evolution of sperm zonadhesin.
2008
Based on pioneering work of Hardy and Garbers, zonadhesin has become one of the best studied sperm ligands in boreoeutherian mammals, both from a biochemical and evolutionary perspective. Zonadhesin is a mosaic-type protein that localizes to the apical head of spermatozoa. In pig, cattle, rabbit and primates, zonadhesin precursor essentially consists of two or three MAM (meprin/A5 antigen/mu receptor tyrosine phosphatase) domains, one mucin-like domain, one incomplete and four complete D domains (homologous to vWFD). Mouse zonadhesin is distinguished from this general pattern by 20 extra partial D3 domains. While concerted evolution drives the divergence of the mucin-like domain in the orth…
Sexual orientation predicts men’s preferences for sexually dimorphic face-shape characteristics: A replication study
2020
Many researchers have proposed that straight men prefer women’s faces displaying feminine shape characteristics at least partly because mating with such women will produce healthier offspring. Although a prediction of thisadaptation-for-mate-choicehypothesis is that straight men will show stronger preferences for feminized versus masculinized versions of women’s faces than will gay men, only one previous study has directly tested this prediction. Here we directly replicated that study by comparing 623 gay and 3163 straight men’s preferences for feminized versus masculinized versions of faces. Consistent with the adaptation-for-mate-choice hypothesis of straight men’s femininity preferences,…
Gender-Related Immune-Inflammatory Factors, Age-Related Diseases, and Longevity
2010
This review discusses the role of estrogens as pro- or antiinflammatory players in immune-inflammatory responses. In particular, their role in Alzheimer’s disease (AD), an example of immune-inflammatory disease, is discussed briefly. AD is a progressive neurodegenerative disease, which in Western societies accounts for the majority of cases of clinical senile dementia. However, sexual dimorphism of diseases may also depend on factors independent of sex hormones (i.e., a gender effect), as demonstrated by our data on differential longevity in females and males. In fact, differences in mortality between men and women are not only a question of sex that refers to biological differences, but ra…
On the socio-sexual behaviour of the extinct ursid Indarctos arctoides: an approach based on its baculum size and morphology
2013
The fossil bacula, or os penis, constitutes a rare subject of study due to its scarcity in the fossil record. In the present paper we describe five bacula attributed to the bear Indarctos arctoides Depéret, 1895 from the Batallones-3 site (Madrid Basin, Spain). Both the length and morphology of this fossil bacula enabled us to make interpretative approaches to a series of ecological and ethological characters of this bear. Thus, we suggest that I. arctoides could have had prolonged periods of intromission and/or maintenance of intromission during the post-ejaculatory intervals, a multi-male mating system and large home range sizes and/or lower population density. Its size might also have he…
Revision of the genus Prionotropis Fieber, 1853 (Orthoptera: Pamphagidae: Thrinchinae)
2015
The genus Prionotropis Fieber, 1853 is revised. It is distributed in scattered areas of the Mediterranean region from Turkey in the East to Spain in the West. Overall, seven species are listed, namely P. maculinervis (Stål, 1878) (Turkey; P. urfensis Ramme, 1933 is here considered its synonym), P. willemsorum n. sp. (Greece, Epirus; previously considered P. appula), P. appula (O.G. Costa, 1836) (South Italy), P. hystrix (Germar, 1817) (Bosnia and Herzegovina, Slovenia, Croatia, North-East Italy; P. hystrix sontiaca is here synonymized), P. rhodanica Uvarov, 1923 resurrected status (France, Crau, Rhone delta; here considered a valid species), P. azami Uvarov, 1923 n. status (France, Var regi…
Remarks on some interesting African Pamphagidae and Acrididae (Insecta: Orthoptera: Acridoidea).
2020
The author reports about the results of a study of Porthetinae (Pamphagidae) and other Acridoidea preserved in some European museums. The taxonomy of African Porthetinae is still poorly known; some genera were established on variable characters (e.g.: the number of the flagellum segments, the shape of the hind femora or the prosternal tubercle) and collections generally hold only few specimens of this group. These insects are characterized by a remarkable sexual dimorphism, the males generally are winged while females are apterous. Because many species were described only from one sex (sometimes the female sex), there are objective difficulties to identify them correctly. The following syno…
Evolution of alternative male morphotypes in oxyurid nematodes: a case of convergence?
2014
Male dimorphism has been reported across different taxa and is usually expressed as the coexistence of a larger morph with exaggerated male traits and a smaller one with reduced traits. The evolution and maintenance of male dimorphism are still poorly understood for several of the species in which it has been observed. Here, we analyse male dimorphism in several species of reptile parasitic nematodes of the genus Spauligodon, in which a major male morph (exaggerated morph), which presents the traditional male morphological traits reported for this taxon, coexists with a minor morph with reduced morphological traits (i.e. reduced genital papillae) resembling more closely the males of the sis…
Genetic identification of neurons controlling a sexually dimorphic behaviour
2000
0960-9822 (Print) Journal Article Research Support, Non-U.S. Gov't; In the fruit fly Drosophila melanogaster, locomotor activity is sexually dimorphic: female flies constantly modulate their activity pattern whereas males show a steadier, stereotyped walking pace [1]. Here, we mapped the area of the brain controlling this behavioural dimorphism. Adult male Drosophila expressing a dominant feminising transgene in a small cluster of neurons in the pars intercerebralis exhibited a female-like pattern of locomotor activity. Genetic ablation of these neurons prevented the feminisation of the locomotor activity of transgenic males. The results suggest that this cluster of neurons modulates sex-sp…
Courtship Behavior of Brain Mosaics in Drosophila
2000
0167-7063 (Print) Journal Article Research Support, Non-U.S. Gov't; Sites in the brain that show functional, sexual dimorphism in courtship behavior have been mapped at high resolution in male/female mosaics of Drosophila melanogaster. The sex mosaics were produced by enhancer-trap expression of GAL4 driving the female-spliced form of the transformer gene (tra), revealing sites in the dorsal brain, lateral protocerebrum, suboesophageal, thoracic and abdominal ganglia, and suggesting the importance of cross-talk between these regions in the implementation of the courtship sequence.