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Cyrtodiopsis Dalmanni
} ''Teleopsis dalmanni'', synonym ''Cyrtodiopsis dalmanni'', also known as the Malaysian stalk-eyed fly, is a species of fly in the family Diopsidae. ''T. dalmanni'' flies possess lateral elongations on their head capsules called eyestalks. These eyestalks play an important role in mate selection and as a result physical characteristic of the fly has been the subject of several studies on sexual selection, natural selection, and mating behavior. Distribution ''Teleopsis dalmanni'' is found in Malaysia as well as other parts of Southeast Asia. Flies used in studies are usually collected in Malaysia. Habitat ''Teleopsis dalmanni'' are predominantly found at the edge of forest streams, where their mating rituals occur. They have been observed resting on dried leaves or undergrowth at the water’s edge, and occasionally even on the sand. Life history As with other Dipterans, ''T. dalmanni'' flies undergo a larval phase before transitioning into adults. There is little infor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teleopsis Dalmanni 2
''Teleopsis'' is a genus of stalk-eyed flies in the family Diopsidae. All species in the genus are found in Asia. About 20 species are described and several others as yet are to be described. Species *'' T. adjacens'' Brunetti, 1928 *'' T. africana'' (Shillito, 1940) *'' Teleopsis amnoni'' *'' T. anjahanaribei'' (Vanschuytbroeck, 1965) *'' T. apographica'' ( Séguy, 1949) *'' T. apollo'' Brunetti, 1928 *'' T. bigoti'' Hendel, 1914 *'' T. boettcheri'' Frey, 1928 *'' T. breviscopium'' Rondani, 1875 *'' T. cheni'' Yang & Chen, 1998 *'' T. cobiae'' Feijen, 2011 *'' T. freyi'' Feijen, 2011 *'' T. fulviventris'' Bigot, 1880 *'' T. krombeini'' Feijen, 1998 *'' T. longiscopium'' Rondani, 1875 *'' T. maculata'' Feijen, 1998 *'' T. motatrix'' Osten Sacken, 1882 *'' T. nitidifacies'' Feijen, 2011 *'' T. nitidiscutum'' Feijen, 2011 *'' T. onopyxus'' Séguy, 1949 *'' T. pallifacies'' Feijen & Feijen, 2011 *'' T. pharao'' Frey Freyr (Old Norse: 'Lord'), sometimes anglicized as Fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sperm
Sperm is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, which are known as spermatozoa, while some red algae and fungi produce non-motile sperm cells, known as spermatia. Flowering plants contain non-motile sperm inside pollen, while some more basal plants like ferns and some gymnosperms have motile sperm. Sperm cells form during the process known as spermatogenesis, which in amniotes ( reptiles and mammals) takes place in the seminiferous tubules of the testes. This process involves the production of several successive sperm cell precursors, starting with spermatogonia, which differentiate into spermatocytes. The spermatocytes then undergo meiosis, reducing their chromosome number by half, which produces spermatids. The spermatids then mature and, in animals, construct a tail, or flagellum, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oocyte
An oocyte (, ), oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell (PGC), which then undergoes mitosis, forming oogonia. During oogenesis, the oogonia become primary oocytes. An oocyte is a form of genetic material that can be collected for cryoconservation. Formation The formation of an oocyte is called oocytogenesis, which is a part of oogenesis. Oogenesis results in the formation of both primary oocytes during fetal period, and of secondary oocytes after it as part of ovulation. Characteristics Cytoplasm Oocytes are rich in cytoplasm, which contains yolk granules to nourish the cell early in development. Nucleus During the primary oocyte stage of oogenesis, the nucleus is called a germinal vesicle. The only normal human type of secondary oocyte has t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', which is when both biological sexes are phenotypically indistinguishable from each other. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerated dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vaginal Cavity
In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen. At the deep end, the cervix (neck of the uterus) bulges into the vagina. The vagina allows for sexual intercourse and birth. It also channels menstrual flow, which occurs in humans and closely related primates as part of the menstrual cycle. Although research on the vagina is especially lacking for different animals, its location, structure and size are documented as varying among species. Female mammals usually have two external openings in the vulva; these are the urethral opening for the urinary tract and the vaginal opening for the genital tract. This is different from male mammals, who usually have a single urethral opening for both urination and reproduction. The vaginal opening is much larger than the nearby urethral opening, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vagina
In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen. At the deep end, the cervix (neck of the uterus) bulges into the vagina. The vagina allows for sexual intercourse and birth. It also channels menstrual flow, which occurs in humans and closely related primates as part of the menstrual cycle. Although research on the vagina is especially lacking for different animals, its location, structure and size are documented as varying among species. Female mammals usually have two external openings in the vulva; these are the urethral opening for the urinary tract and the vaginal opening for the genital tract. This is different from male mammals, who usually have a single urethral opening for both urination and reproduction. The vaginal opening is much larger than the nearby urethral opening, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermatophore
A spermatophore or sperm ampulla is a capsule or mass containing spermatozoa created by males of various animal species, especially salamanders and arthropods, and transferred in entirety to the female's ovipore during reproduction. Spermatophores may additionally contain nourishment for the female, in which case it is called a nuptial gift, as in the instance of bush crickets. In the case of the toxic moth ''Utetheisa ornatrix'', the spermatophore includes sperm, nutrients, and pyrrolizidine alkaloids which prevent predation because it is poisonous to most organisms. However, in some species such as the Edith's checkerspot butterfly, the "gift" provides little nutrient value. The weight of the spermatophore transferred at mating has little effect on female reproductive output. Arthropods Spermatophores are the norm in arachnids and several soil arthropods. In various insects, such as bush crickets, the spermatophore is often surrounded by a proteinaceous spermatophylax. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gourd
Gourds include the fruits of some flowering plant species in the family Cucurbitaceae, particularly ''Cucurbita'' and ''Lagenaria''. The term refers to a number of species and subspecies, many with hard shells, and some without. One of the earliest domesticated types of plants, subspecies of the bottle gourd, ''Lagenaria siceraria'', have been discovered in archaeological sites dating from as early as 13,000 BCE. Gourds have had numerous uses throughout history, including as tools, musical instruments, objects of art, film, and food. Terminology ''Gourd'' is occasionally used to describe crop plants in the family Cucurbitaceae, like pumpkins, cucumbers, squash, luffa, and melons. More specifically, ''gourd'' refers to the fruits of plants in the two Cucurbitaceae genera ''Lagenaria'' and ''Cucurbita'', or also to their hollow, dried-out shell. There are many different gourds worldwide. The main plants referred to as gourds include several species from the genus ''Cucurbita'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copulation (zoology)
In zoology, copulation is animal sexual behavior in which a male introduces sperm into the female's body, especially directly into her reproductive tract. This is an aspect of mating. Many animals that live in water use external fertilization, whereas internal fertilization may have developed from a need to maintain gametes in a liquid medium in the Late Ordovician epoch. Internal fertilization with many vertebrates (such as all reptiles, some fish, and most bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...s) occurs via cloacal copulation, known as cloacal kiss (see also hemipenis), while mammals copulate vaginally, and many primitive (biology), basal vertebrates reproduce sexually with external fertilization. In spiders and insects Spiders are often confused with insects, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptivity
{{Multiple issues, {{refimprove, date=December 2014{{one source, date=December 2014 Receptivity, or receptive agency, is a practical capacity and source of normativity, discussed and developed in various ways by writers such as Ralph Waldo Emerson, Stanley Cavell and Martin Heidegger, among others. According to the philosopher Nikolas Kompridis Nikolas Kompridis (; born 1953) is a Canadian philosopher and political theorist. His major published work addresses the direction and orientation of Frankfurt School critical theory; the legacy of philosophical romanticism; and the aesthetic dim ..., who has argued for its importance to democracy, democratic politics, romanticism and critical theory, the term has both ontology, ontological and ethical dimensions, and refers to a mode of listening and "normative response" to demands arising outside the self, as well as "a way by which we might become more attuned to our world disclosure, pre-reflective understanding of the world, to our i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harem (zoology)
A harem is an animal group consisting of one or two males, a number of females, and their offspring. The dominant male drives off other males and maintains the unity of the group. If present, the second male is subservient to the dominant male. As juvenile males grow, they leave the group and roam as solitary individuals or join bachelor herds. Females in the group may be inter-related. The dominant male mates with the females as they become sexually active and drives off competitors, until he is displaced by another male. In some species, incoming males that achieve dominant status may commit infanticide. For the male, the primary benefit of the harem system is obtaining exclusive access to a group of mature females. The females benefit from being in a stable social group and the associated benefits of grooming, predator avoidance and cooperative defense of territory. The disadvantages for the male are the energetic costs of gaining or defending a harem which may leave him with r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
