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Abstract

In Tanaidacea morphological identification of male individuals to the species level is complicated by two factors: the presence of multiple male stages/instars confuse the assessment of sexual stage while strong sexual dimorphism within several families obscures the morphological affinities of undescribed males to described females. Males of Paratanaoidea are often morphologically quite different from females and have not been discovered for most genera so far, which has led to the assumption that some tanaidaceans might have parthenogenetic reproduction or simply have undeveloped secondary sex traits. As a part of the IceAGE project (Icelandic marine Animals: Genetics and Ecology), with the support of molecular methods, the first evidence for the existence of highly dimorphic (swimming) males in four families of the superfamily Paratanaoidea (Agathotanaidae, Cryptocopidae, Akanthophoreidae, and Typhlotanaidae) is presented. This study suggests that these males might be the next instars after juvenile or preparatory males, which are morphologically similar to females. It has been assumed that “juvenile” males with a restricted ability for swimming ( e.g. , undeveloped pleopods) have matured testes, are capable of reproduction, and mate with females nearby, while swimming males can mate with distant females. Our explanation of the dimorphism in Tanaidomorpha lies in the fact that males of some species ( e.g. , Nototanais ) retain the same lifestyle or niche as the females, so secondary traits improve their ability to guard females and successfully mate. Males of other species that have moved into a regime (niche) different than that of the female have acquired complex morphological changes ( e.g. , Typhlotanais ).
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Abstract

Our macroscopic observations and microscopic studies conducted by means of a light microscope (LM) and transmission electron microscope (TEM) concerning the reproduction biology of Colobanthus quitensis (Caryophyllaceae) growing in natural conditions in the Antarctic and in a greenhouse in Olsztyn (northern Poland) showed that this plant develops two types of bisexual flowers: opening, chasmogamous flowers and closed, cleistogamous ones. Cleistogamy was caused by a low temperature, high air humidity and strong wind. A small number of microspores differentiated in the microsporangia of C. quitensis , which is typical of cleistogamous species. Microsporocytes, and later micro − spores, formed very thick callose walls. More than twenty spheroidal, polypantoporate pollen grains differentiated in the microsporangium. They germinated on the surface of receptive cells on the dry stigma of the gynoecium or inside the microsporangium. A monosporic embryo sac of the Polygonum type differentiated in the crassinucellar ovule. During this differentiation the nucellus tissue formed and stored reserve materials. In the development of generative cells, a male germ unit (MGU) with differentiated sperm cells was observed. The smaller cell contained mainly mitochondria, and the bigger one plastids. In the process of fertilization in C. quitensis only one nucleus of the sperm cell, without cytoplasm fragments, entered the egg cell, and the proembryo developed according to the Caryophyllad type. Almost all C. quitensis ovules developed and formed perispermic seeds with a completely differentiated embryo both under natural conditions in the Antarctic and in a greenhouse in Olsztyn.
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Abstract

The discourse on homosexually has largely remained Euro-American with a focus on human right of African homosexuals residing in Africa. However, current debates in Africa have centered on the cultural acceptability, legality as well as mental health concerns presumed to be associated with homosexuality. The paper approaches the issue of homosexuality from a perspective that is sensitive to the cultural context of Ghana and also through a non-Euro-American lens. The author attempts to address some of the misunderstanding about the legal status of homosexuals and the negative attitudes in Ghana. The paper concludes that Ghanaians face a paradox of accepting homosexuality because it cannot be understood to further growth of human society from their perspective. Similarly, if Ghanaians view homosexuality as a mental health issue, then it is more appropriate to decriminalize it as it is not appropriate to criminalize mental disorders. Reconceptualizing the issue as a human rights one in which both anti- and pro-homosexual religious and sexual rights respectively are accommodated may be more progressive than promoting one set of rights at the expense of the other. Though Ghana is the focus of this paper, it is believed that the discussions presented are applicable to the rest of Africa and other non-Western societies.
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Abstract

The purpose of this two-wave longitudinal study was to investigate cross-lagged relations between sexual attitudes, perception of love and sex, and young adults’ relationship status over a period of one year. The current study tested two hypotheses: the first hypothesis assuming that sexual attitudes, perception of love and sex can be predictive of relationship status after a one-year interval; and the second hypothesis assuming that relationship status at T1 can be predictive of sexual attitudes and perception of love and sex after a one-year interval. Results from 117 Polish young adults (94 females and 23 males) aged 20–33 (M = 21.42, SD = 1.79) indicated that the conviction that sex is no longer as much a part of the relationship as it used to be (i.e., Sex is Declining scale) measured in the first assessment was a significant predictor of relationship status after a one-year interval. Furthermore, sexual attitudes and perception of love and sex at T1 were found to be predictive of sexual attitudes and perception of love and sex at T2. In addition, gender at T1 was predictive of instrumentality at T2, while being female at T1 related to higher instrumentality at T2.
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