|
Cyclommatus Metallifer
''Cyclommatus metallifer'' is a species of stag beetle in the family Lucanidae. There is sexual dimorphism within the species. Males are generally larger in size and have enlarged mandibles. It is named for its metallic coloration, which ranges in color and may be varying levels of black, brown, or gold. This species is notably easy to maintain, making it a useful species for scientific study. Additionally, it has been kept as an exotic pet. Description ''C. metallifer'' exhibits extreme sexual dimorphism, where males are larger than females and have long mandibles. These mandibles are important for sexual selection, and males use them in competition. To compensate for the weakened bite force caused by their long mandibles, males of this species have larger head muscles than females. Because their entire head morphology is specialized for sexual selection, both the head and mandibles can be considered key components of their armaments. Because their bites are so powerful, thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean Baptiste Boisduval
Jean Baptiste Alphonse Déchauffour de Boisduval (24 June 1799 – 30 December 1879) was a French lepidopterist, botanist, and physician. He was one of the most celebrated lepidopterists of France, and was the co-founder of the Société entomologique de France. While best known abroad for his work in entomology, he started his career in botany, collecting a great number of French plant specimens and writing broadly on the topic throughout his career, including the textbook ''Flores française'' in 1828. Early in his career, he was interested in Coleoptera and allied himself with both Jean Théodore Lacordaire and Pierre André Latreille. He was the curator of the Pierre Françoise Marie Auguste Dejean collection in Paris and described many species of beetles, as well as butterflies and moths, resulting from the voyages of the ''Astrolabe'', the expedition ship of Jean-François de Galaup, comte de La Pérouse and the '' Coquille'', that of Louis Isidore Duperrey. He left Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lucanidae
Stag beetles are a family of about 1,200 species of beetles in the family Lucanidae, currently classified in four subfamilies.Smith, A.B.T. (2006). A review of the family-group names for the superfamily Scarabaeoidea (Coleoptera) with corrections to nomenclature and a current classification. The Coleopterists Bulletin 60:144–204. Some species grow to over , but most to about . Overview The English name is derived from the large and distinctive mandibles found on the males of most species, which resemble the antlers of stags. A well-known species in much of Europe is ''Lucanus cervus'', referred to in some European countries (including the United Kingdom) as ''the'' stag beetle; it is the largest terrestrial insect in Europe. Pliny the Elder noted that Nigidius called the beetle ''lucanus'' after the Italian region of Lucania where they were used as amulets. The scientific name of ''Lucanus cervus'' adds ''cervus'', deer. Male stag beetles are known for their oversize mandi ... [...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 exaggerat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandible (insect Mouthpart)
Insect mandibles are a pair of appendages near the insect's mouth, and the most anterior of the three pairs of oral appendages (the labrum is more anterior, but is a single fused structure). Their function is typically to grasp, crush, or cut the insect's food, or to defend against predators or rivals. Insect mandibles, which appear to be evolutionarily derived from legs, move in the horizontal plane unlike those of vertebrates, which appear to be derived from gill arches and move vertically. Grasshoppers, crickets, and other simple insects The mouthparts of orthopteran insects are often used as a basic example of mandibulate (chewing) mouthparts, and the mandibles themselves are likewise generalized in structure. They are large and hardened, shaped like pinchers, with cutting surfaces on the distal portion and chewing or grinding surfaces basally. They are usually lined with teeth and move sideways. Large pieces of leaves can therefore be cut and then pulverized near the mouth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Selection
Sexual selection is a mode of natural selection in which members of one biological sex choose mates of the other sex to mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex (intrasexual selection). These two forms of selection mean that some individuals have greater reproductive success than others within a population, for example because they are more attractive or prefer more attractive partners to produce offspring. Successful males benefit from frequent mating and monopolizing access to one or more fertile females. Females can maximise the return on the energy they invest in reproduction by selecting and mating with the best males. The concept was first articulated by Charles Darwin who wrote of a "second agency" other than natural selection, in which competition between mate candidates could lead to speciation. The theory was given a mathematical basis by Ronald Fisher in the early 20th century. Sexual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Ornament
A biological ornament is a characteristic of an animal that appears to serve a decorative function rather than a utilitarian function. Many are secondary sexual characteristics, and others appear on young birds during the period when they are dependent on being fed by their parents. Ornaments are used in displays to attract mates, which may lead to the evolutionary process known as sexual selection. An animal may shake, lengthen, or spread out its ornament in order to get the attention of the opposite sex, which will in turn choose the most attractive one with which to mate. Ornaments are most often observed in males, and choosing an extravagantly ornamented male benefits females as the genes that produce the ornament will be passed on to her offspring, increasing their own reproductive fitness. As Ronald Fisher noted, the male offspring will inherit the ornament while the female offspring will inherit the preference for said ornament, which can lead to a positive feedback loop k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanoreceptors
A mechanoreceptor, also called mechanoceptor, is a sensory receptor that responds to mechanical pressure or distortion. Mechanoreceptors are innervated by sensory neurons that convert mechanical pressure into electrical signals that, in animals, are sent to the central nervous system. Vertebrate mechanoreceptors Cutaneous mechanoreceptors Cutaneous mechanoreceptors respond to mechanical stimuli that result from physical interaction, including pressure and vibration. They are located in the skin, like other cutaneous receptors. They are all innervated by Aβ fibers, except the mechanorecepting free nerve endings, which are innervated by Aδ fibers. Cutaneous mechanoreceptors can be categorized by what kind of sensation they perceive, by the rate of adaptation, and by morphology. Furthermore, each has a different receptive field. By sensation *The Slowly Adapting type 1 (SA1) mechanoreceptor, with the Merkel corpuscle end-organ (also known as Merkel discs) detect sustained ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guinea. Indonesia is the world's largest archipelagic state and the 14th-largest country by area, at . With over 275 million people, Indonesia is the world's fourth-most populous country and the most populous Muslim-majority country. Java, the world's most populous island, is home to more than half of the country's population. Indonesia is a presidential republic with an elected legislature. It has 38 provinces, of which nine have special status. The country's capital, Jakarta, is the world's second-most populous urban area. Indonesia shares land borders with Papua New Guinea, East Timor, and the East Malaysia, eastern part of Malaysia, as well as maritime borders with Singapore, Vietnam, Thailand, the Philippines, Australia, Palau, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maluku Islands
The Maluku Islands (; Indonesian: ''Kepulauan Maluku'') or the Moluccas () are an archipelago in the east of Indonesia. Tectonically they are located on the Halmahera Plate within the Molucca Sea Collision Zone. Geographically they are located east of Sulawesi, west of New Guinea, and north and east of Timor. Lying within Wallacea (mostly east of the biogeographical Weber Line), the Maluku Islands have been considered as a geographical and cultural intersection of Asia and Oceania. The islands were known as the Spice Islands because of the nutmeg, mace and cloves that were exclusively found there, the presence of which sparked colonial interest from Europe in the sixteenth century. The Maluku Islands formed a single province from Indonesian independence until 1999, when it was split into two provinces. A new province, North Maluku, incorporates the area between Morotai and Sula, with the arc of islands from Buru and Seram to Wetar remaining within the existing Maluk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulawesi
Sulawesi (), also known as Celebes (), is an island in Indonesia. One of the four Greater Sunda Islands, and the world's eleventh-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Mindanao and the Sulu Archipelago. Within Indonesia, only Sumatra, Borneo, and Papua are larger in territory, and only Java and Sumatra have larger populations. The landmass of Sulawesi includes four peninsulas: the northern Minahasa Peninsula, the East Peninsula, the South Peninsula, and the Southeast Peninsula. Three gulfs separate these peninsulas: the Gulf of Tomini between the northern Minahasa and East peninsulas, the Tolo Gulf between the East and Southeast peninsulas, and the Bone Gulf between the South and Southeast peninsulas. The Strait of Makassar runs along the western side of the island and separates the island from Borneo. Etymology The name ''Sulawesi'' possibly comes from the words ''sula'' ("island") and ''besi'' ("iron") and may ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juvenile Hormone
Juvenile hormones (JHs) are a group of acyclic sesquiterpenoids that regulate many aspects of insect physiology. The first discovery of a JH was by Vincent Wigglesworth. JHs regulate development, reproduction, diapause, and polyphenisms.The chemical formula for juvenile hormone is C_18H_30O_3. In insects, JH (formerly called neotenin) refers to a group of hormones, which ensure growth of the larva, while preventing metamorphosis. Because of their rigid exoskeleton, insects grow in their development by successively shedding their exoskeleton (a process known as molting). Juvenile hormones are secreted by a pair of endocrine glands behind the brain called the corpora allata. JHs are also important for the production of eggs in female insects. JH was isolated in 1965 by Karel Sláma and Carroll Williams and the first molecular structure of a JH was solved in 1967. Most insect species contain only juvenile growth hormone (JH) III. To date JH 0, JH I, and JH II have been ide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doublesex
''Doublesex'' (''dsx'') is a gene that is involved in the sex determination system of many insects including the fruit fly ''Drosophila melanogaster''. Sex determination The gene is expressed in both male and female flies and is subject to alternative splicing, producing the protein isoforms ''dsxf'' in females and the longer ''dsxm'' in males. The production of ''dsxf'' is caused by the presence of the female-specific version of the ''transformer'' (''tra'') gene. In a sense, the isoform of ''dsx'' informs a cell about the organism's sex; for instance, female genitals only develop if ''dsxf'' is present. In conjunction with the gene ''fruitless'', ''dsx'' also causes differences in the brain structure and behavior of males and females. Lay summary: Although the details of sex determination differ in the various species, there is a gene related to ''dsx'' in vertebrates (DMRT1) and in nematodes ( MAB-3). All of these are transcription factors with a zinc finger DNA-binding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
