Gynandromorphs and intersexes: potential to understand the mechanism of sex determination in arthropods

2010 ◽  
Vol 3 (1) ◽  
pp. 63-96 ◽  
Author(s):  
Rodrigo Pereira ◽  
Satoko Narita ◽  
Daisuke Kageyama ◽  
Finn Kjellberg
Keyword(s):  
Sex Chromosome ◽  
Morphological Characters ◽  
The Other ◽  
Sexually Dimorphic ◽  
Double Fertilization ◽  
Low Frequencies ◽  
Causal Factors ◽  
Male And Female ◽  
Sexual Phenotype ◽  
Laboratory Populations

AbstractArthropods are sexually dimorphic. An arthropod individual usually differentiates into a male or a female. With very low frequencies, however, individuals with both male and female morphological characters have repeatedly been found in natural and laboratory populations of arthropods. Gynandromorphs (i.e., sexual mosaics) are genetically chimeric individuals consisting of male and female tissues. On the other hand, intersexes are genetically uniform (i.e., complete male, complete female or intermediate in every tissue) but all or some parts of their tissues have either a sexual phenotype opposite to their genetic sex or an intermediate sexual phenotype. Possible developmental processes (e.g., double fertilization of a binucleate egg, loss of a sex chromosome or upregulation/downregulation of sex-determining genes) and causal factors (e.g., mutations, genetic incompatibilities, temperatures or endosymbionts) for the generation of gynandromorphs and intersexes are reviewed and discussed.

scholarly journals The sex with the reduced sex chromosome dies earlier: a comparison across the tree of life

2020 ◽  
Vol 16 (3) ◽  
pp. 20190867 ◽  
Author(s):  
Zoe A. Xirocostas ◽  
Susan E. Everingham ◽  
Angela T. Moles
Keyword(s):  
Sex Chromosome ◽  
Meta Analysis ◽  
Chromosome Morphology ◽  
Tree Of Life ◽  
The Other ◽  
Deleterious Mutations ◽  
Male And Female ◽  
Fundamental Understanding ◽  
Female Longevity ◽  
Heterogametic Sex

Many taxa show substantial differences in lifespan between the sexes. However, these differences are not always in the same direction. In mammals, females tend to live longer than males, while in birds, males tend to live longer than females. One possible explanation for these differences in lifespan is the unguarded X hypothesis, which suggests that the reduced or absent chromosome in the heterogametic sex (e.g. the Y chromosome in mammals and the W chromosome in birds) exposes recessive deleterious mutations on the other sex chromosome. While the unguarded X hypothesis is intuitively appealing, it had never been subject to a broad test. We compiled male and female longevity data for 229 species spanning 99 families, 38 orders and eight classes across the tree of life. Consistent with the unguarded X hypothesis, a meta-analysis showed that the homogametic sex, on average, lives 17.6% longer than the heterogametic sex. Surprisingly, we found substantial differences in lifespan dimorphism between female heterogametic species (in which the homogametic sex lives 7.1% longer) and male heterogametic species (in which the homogametic sex lives 20.9% longer). Our findings demonstrate the importance of considering chromosome morphology in addition to sexual selection and environment as potential drivers of sexual dimorphism, and advance our fundamental understanding of the mechanisms that shape an organism's lifespan.

Zunielmis pax, a new genus and species of riffle beetles (Coleoptera: ­Elmidae) from Colombia

2021 ◽  
Vol 30 (2) ◽  
pp. 248-265
Author(s):  
M. González-Córdoba ◽  
V. Manzo ◽  
C.E. Granados-Martínez
Keyword(s):  
New Species ◽  
River Basin ◽  
New Genus ◽  
Morphological Characters ◽  
The Other ◽  
Female Genitalia ◽  
Lateral Margin ◽  
New Genus And Species ◽  
Freshwater Sponges ◽  
Male And Female

A new riffle beetle, Zunielmis pax gen. et sp. nov., is described from Colombia (Vichada, Puerto Carreño, Bita River basin). It can be distinguished from all the other elmids by having large areas of a microgranular mesh (plastron) on the pronotum and elytra, crenulate lateral margin of the latter two, the shorter interocular distance than diameter of each eye, as well as by the characters of the structure of mandibles, the shape and sculpture of pronotum, and the structure of mesosternum, mesotibiae and elytra. The imagoes were collected on freshwater sponges. The habitat, where the new species was found, is described, and the adaptive meaning of the characteristics of plastron are discussed. Drawings and photographs of the adult habitus, distinctive morphological characters, and male and female genitalia are provided.

Items’ Cross-Category Associations as a Confounding Factor in the Implicit Association Test

2001 ◽  
Vol 48 (2) ◽  
pp. 123-134 ◽  
Author(s):  
Melanie C. Steffens ◽  
Inga Plewe
Keyword(s):  
Implicit Association Test ◽  
Confounding Factor ◽  
Reaction Times ◽  
Association Test ◽  
The Other ◽  
Reaction Time Difference ◽  
Implicit Association ◽  
Male And Female ◽  
Research Activities ◽  
Degree Of Association

Abstract. The introduction of the Implicit Association Test (IAT; Greenwald, McGhee, & Schwartz, 1998 ) has stimulated numerous research activities. The IAT is supposed to measure the degree of association between concepts. Instances have to be assigned to these concepts by pressing appropriate keys as quickly as possible. The reaction time difference between certain conditions, termed the IAT effect, is used as an indicator of the degree of the concepts’ association. We tested the hypothesis that the degree of association between one concept (or category) and the instances of the other presented concept also influences reaction times. In our experiment, the instances in the target categories, male and female names, were kept constant. The adjectives in the evaluative categories were manipulated: Either the pleasant adjectives were female-associated and the unpleasant adjectives were male-associated, or vice versa. These stereotypic associations were indeed found to exert a substantial influence on the size of the IAT effect. This finding casts doubt on the assumption that the IAT effect may be interpreted as a pure measure of the degree of association between concepts.

LANGUAGE USE BETWEEN MALE AND FEMALE HOST IN HITAM PUTIH TALK SHOW

2018 ◽  
Vol 14 (2) ◽  
Author(s):  
Nurmaliana Sari ◽  
Sumarsih Sumarsih ◽  
Busmin Gurning
Keyword(s):  
Language Use ◽  
The Other ◽  
Male And Female ◽  
Talk Show ◽  
Dominant Language ◽  
Other Hand ◽  
Domestic Activities ◽  
Female Host ◽  
Negative Connotation ◽  
Descriptive Qualitative

This study discusses about language use occurred by male and female host in Hitam Putih talk show. The method of this research is descriptive qualitative. The subjects of this study are male and female host in Hitam Putih talk show. The data are the utterances produced by male and female host in Hitam Putih talk show. This research focuses on the show broadcasted on October 2016 by taking 4 videos randomly. The objective of this study is to describe kinds of the language use uttered by male and female host in Hitam Putih talk show. The findings showed that the kinds of language use consist of 6 parts. The dominant language use uttered by male host is expletive, because male’s utterances are frequently stated in a negative connotation. On the other hand, female host utterances are found in specialized vocabulary as the most dominant because female host has more interest in talking family affairs, such as the education of children, clothes, cooking, and fashion, etc. Women also tended to talk about one thing related to the home and domestic activities. However, the representation of language use uttered by male and female are deficit, dominance and different. Keywords: Language Use, Gender, Talk Show

UV ability to inactivate microorganisms combined with factors affecting radiation

1997 ◽  
Vol 35 (11-12) ◽  
pp. 107-112 ◽  
Author(s):  
A. M. Shaban ◽  
G. E. El-Taweel ◽  
G. H. Ali
Keyword(s):  
Microbial Communities ◽  
Uv Radiation ◽  
Contact Time ◽  
Tap Water ◽  
Scenedesmus Obliquus ◽  
Morphological Characters ◽  
The Other ◽  
Bacterial Cells ◽  
Dark Repair ◽  
Nile Water

In the present study, the effect of UV radiation on the inactivation of a range of microorganisms was studied. Each organism was seeded into sterile tap water and exposed to UV in batch experiments with changing turbidities. In addition, the effect of UV on microbial communities in river Nile water was examined. It was found that 1min contact time (0.5L/min flow rate) was effective against vegetative cells levels almost reaching zero (except with Staphylococcus aureus). On the other hand, spore-forming bacteria, Candida albicans and coliphage were more resistant to UV. This contact time caused coenobia cells in single form with Scenedesmus obliquus while for Microcystis aeruginosa colonies broke into smaller groups. Exposure of Nile water microbial communities to UV showed that yeasts and Aeromonas survived better than the other organisms while in the phytoplankton partial fragmentation occurred in some algal groups. The protective effect of turbidity differed between organisms, with increased contact time under conditions of stable turbidity having no effect on the organisms. At 20 NTU the UV radiation had no effect on the morphological characters of algal cells. In reactivation experiments, it is clear that photoreactivation, and not dark repair, takes place with bacterial cells. Only coliphage had no photoreactivation and dark repair responses although with coliphage and host, both reactivation processes worked well. Moreover, the irradiated algae regained their normal shape after 3 days in suitable media and enough light.

Taxonomy of Neomuscina Townsend (Diptera, Muscidae) from Brazil

Zootaxa ◽  
2012 ◽  
Vol 3504 (1) ◽  
pp. 1 ◽  
Author(s):  
ALESSANDRE PEREIRA-COLAVITE ◽  
CLAUDIO J. B. DE CARVALHO
Keyword(s):  
New Species ◽  
Species Distributions ◽  
Morphological Characters ◽  
Minas Gerais ◽  
Identification Key ◽  
Male And Female ◽  
Number Of Species ◽  
Three New Species ◽  
New Distribution

Neomuscina Townsend includes 41 species distributed throughout the Nearctic and Neotropical Regions. Although the genus has a large number of species, it has been ignored and its taxonomy is confusing and has many flaws. In this work we analyzed the following species recorded for Brazil: Neomuscina atincta Snyder, N. atincticosta Snyder, N. capalta Snyder, N. currani Snyder, N. douradensis Lopes & Khouri, N. goianensis Lopes & Khouri, N. inflexa (Stein), N. instabilis Snyder, N. mediana Snyder, N. mimosa Lopes & Khouri, N. neosimilis Snyder, N. nigricosta Snyder, N. paramediana Lopes & Khouri, N. pictipennis pictipennis (Bigot), N. ponti Lopes & Khouri, N. sanespra Snyder, N. schadei Snyder, N. similata Snyder, N. stabilis (Stein), N. transporta Snyder, N. vitoriae Lopes & Khouri and N. zosteris (Shannon & Del Ponte). Neomuscina nigricosta and N. transporta are new distribution records for Brazil. Three new species are described: Neomuscina anajeensis sp. nov. from Anagé (Bahia), Neomuscina maculata sp. nov. from Botelhos (Minas Gerais) and Neomuscina snyderi sp. nov. from Mata de São João (Bahia). An identification key based on the morphological characters of both male and female is provided. Species distributions are discussed and updated, and the number of species now recorded for Brazil is 29.

BIOCHEMICAL STUDIES ON SOCKEYE SALMON DURING SPAWNING MIGRATION: IV. THE NON-PROTEIN NITROGENOUS CONSTITUENTS OF THE MUSCLE

1958 ◽  
Vol 36 (8) ◽  
pp. 833-838 ◽  
Author(s):  
J. D. Wood
Keyword(s):  
Sockeye Salmon ◽  
The Other ◽  
Spawning Migration ◽  
Female Fish ◽  
Male And Female ◽  
Low Level ◽  
Early Stages ◽  
Biochemical Studies

The non-protein nitrogenous constituents of muscle of migrating sockeye salmon were investigated. These constituents were found to be the same in both male and female fish and were present in approximately the same amounts in both sexes. The histidine content of the muscle in all fish decreased to one fifth of the original value during the early stages of the migratory journey and remained at the low level thereafter. Some of the other constituents changed to a smaller extent, usually increasing in the later stages of the migration. This was especially noticeable in female fish. However, the increase in the concentration of these constituents in the muscle was due to a decrease in the amount of muscle in the fish rather than to an increase in the amounts of the compounds themselves.

scholarly journals Recombination of Ty elements in yeast can be induced by a double-strand break.

Genetics ◽  
1995 ◽  
Vol 140 (1) ◽  
pp. 67-77 ◽  
Author(s):  
A Parket ◽  
O Inbar ◽  
M Kupiec
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Strand Break ◽  
Double Strand Break ◽  
The Other ◽  
Direct Repeats ◽  
Yeast Saccharomyces Cerevisiae ◽  
Low Frequencies ◽  
Ty Elements ◽  
Main Family

Abstract The Ty retrotransposons are the main family of dispersed repeated sequences in the yeast Saccharomyces cerevisiae. These elements are flanked by a pair of long terminal direct repeats (LTRs). Previous experiments have shown that Ty elements recombine at low frequencies, despite the fact that they are present in 30 copies per genome. This frequency is not highly increased by treatments that cause DNA damage, such as UV irradiation. In this study, we show that it is possible to increase the recombination level of a genetically marked Ty by creating a double-strand break in it. This break is repaired by two competing mechanisms: one of them leaves a single LTR in place of the Ty, and the other is a gene conversion event in which the marked Ty is replaced by an ectopically located one. In a strain in which the marked Ty has only one LTR, the double-strand break is repaired by conversion. We have also measured the efficiency of repair and monitored the progression of the cells through the cell-cycle. We found that in the presence of a double-strand break in the marked Ty, a proportion of the cells is unable to resume growth.

A large new species of Rhinella (Anura: Bufonidae) from Cerrado of Brazil

Zootaxa ◽  
2007 ◽  
Vol 1627 (1) ◽  
pp. 23-39 ◽  
Author(s):  
NATAN M. MACIEL ◽  
REUBER A. BRANDÃO ◽  
LEANDRO A. CAMPOS ◽  
ANTONIO SEBBEN
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Morphological Characters ◽  
Morphological Features ◽  
Advertisement Call ◽  
Sexually Dimorphic ◽  
Rhinella Marina ◽  
Large Size ◽  
Morphometric Feature ◽  
Distrito Federal

A new toad, Rhinella cerradensis, is described, including its tadpole and the advertisement call. The new species occupies Cerrado habitats in the Brazilian states of Piauí, Bahia, Goiás, Minas Gerais, and Distrito Federal. The species is characterized by its large size; absence of tibial glands; well developed cranial crests; short hands; sexually dimorphic coloration; and by the absence of a spiracle tube of the tadpole. The new species is included in the Rhinella marina group by the presence of a jagged suture formed by the articulation between the pterygoid medial ramus and the parasphenoid alae, as well as other shared morphological features. Morphological characters and statistical analyses inferred by morphometric feature suggest the existence of two subgroups of species within R. marina group. However, taxonomic rearrangements are not made here and await phylogenetic analysis.

The five‐factor personality model in applied settings

1994 ◽  
Vol 8 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Itzhak Montag ◽  
Joseph Levin
Keyword(s):  
Factor Analysis ◽  
Personality Inventory ◽  
The Other ◽  
Factor Solution ◽  
Male And Female ◽  
Neo Personality Inventory ◽  
Clear Cut ◽  
Five Factors ◽  
Male Subjects ◽  
Female Subjects

Two studies of the Revised NEO‐Personality Inventory (NEO‐PI‐R) conducted on two different applicant samples (one consisting of 539 female subjects and the other consisting of 396 male subjects) are reported. Factor analysis of the female sample yielded a five‐factor solution, highly congruent with the factors presented by Costa, McCrae and Dye (1991). Results of the male data were less clear‐cut, yielding four to five factors which were moderately congruent with the American data. The combined male and female sample showed again high congruence coefficients. Various minor deviations in the location of the facet variables are discussed.

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