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Pupate
A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages thereof being egg, larva, pupa, and imago. The processes of entering and completing the pupal stage are controlled by the insect's hormones, especially juvenile hormone, prothoracicotropic hormone, and ecdysone. The act of becoming a pupa is called pupation, and the act of emerging from the pupal case is called eclosion or emergence. The pupae of different groups of insects have different names such as ''chrysalis'' for the pupae of butterflies and ''tumbler'' for those of the mosquito family. Pupae may further be enclosed in other structures such as cocoons, nests, or shells. Position in life cycle The pupal stage follows the larval stage, or in some cases a prepupal stage, and precedes adulthood (''imago'') in insects with complete meta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monarch Butterflies
The monarch butterfly or simply monarch (''Danaus plexippus'') is a milkweed butterfly (subfamily Danainae) in the family Nymphalidae. Other common names, depending on region, include milkweed, common tiger, wanderer, and black-veined brown. It is among the most familiar of North American butterflies and an iconic pollinator, although it is not an especially effective pollinator of milkweeds. Its wings feature an easily recognizable black, orange, and white pattern, with a wingspan of . A Müllerian mimic, the viceroy butterfly, is similar in color and pattern, but is markedly smaller and has an extra black stripe across each hindwing. The eastern North American monarch population is notable for its annual southward late-summer/autumn instinctive migration from the northern and central United States and southern Canada to Florida and Mexico. During the fall migration, monarchs cover thousands of miles, with a corresponding multigenerational return north in spring. The west ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysalis
A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages thereof being egg, larva, pupa, and imago. The processes of entering and completing the pupal stage are controlled by the insect's hormones, especially juvenile hormone, prothoracicotropic hormone, and ecdysone. The act of becoming a pupa is called pupation, and the act of emerging from the pupal case is called eclosion or emergence. The pupae of different groups of insects have different names such as #Chrysalis, ''chrysalis'' for the pupae of butterflies and ''tumbler'' for those of the mosquito family. Pupae may further be enclosed in other structures such as #Cocoon, cocoons, nests, or Exoskeleton, shells. Position in life cycle The pupal stage follows the larval stage, or in some cases a prepupal stage, and precedes adulthood (''imago'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prepupa
The prepupa is a stage in the life cycle of certain Insect, insects, following the larva or Nymph (biology), nymph and preceding the pupa. It occurs in both Holometabolism, holometabolous and Hemimetabolism, hemimetabolous insects. Examples Coleoptera Coccinellidae, Lady beetles have a prepupa stage. In ''Coleomegilla maculata'', this lasts up to 24 hours. A larva enters the stage by attaching its rear Abdomen, abdominal segments to a leaf, and its body becomes stiff and curved. It does not move unless provoked (e.g. by a predator attacking it), in which case it moves to escape the threat. In the stag beetle ''Cyclommatus metallifer'', the prepupa involves four distinct stages. The first lasts 2 days and involves a beetle larva constructing its pupal cell. The second lasts 3-4 days and involves the prepupa purging the contents of its gut, also changing shape in the process. The third stage, in which the prepupa undergoes Cell proliferation, proliferation of adult tissues, l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prothoracicotropic Hormone
Prothoracicotropic hormone (PTTH) was the first insect hormone to be discovered. It was originally described simply as "brain hormone" by early workers such as Stefan Kopeć (1922) and Vincent Wigglesworth (1934), who realized that ligation of the head of immature insects could prevent molting or pupation of the body region excluded from the head if the ligation was performed before a critical age in the lifestage was reached. After a certain point the ligation had no effect and both sections of the insect would molt or pupate. However, implantation of a conspecific brain to a sessile ligated abdomen or an abdomen under diapause would induce molting or pupation. Thus, the brain was originally thought to be the source of the hormone that induces molting in insects. Later it was established that the insect brain produces a number of hormones, but the hormone which was the cause of the observations made by Kopeć and Wigglesworth was prothoracicotropic hormone. PTTH is secreted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imaginal Disc
An imaginal disc is one of the parts of a holometabolous insect larva that will become a portion of the outside of the adult insect during the pupal transformation to the imago. Contained within the body of the larva, there are pairs of discs that will form, for instance, the wings or legs or antennae or other structures in the adult. The role of the imaginal disc in insect development was first elucidated by Jan Swammerdam. During the pupal stage, many larval structures are broken down, and adult structures, including the discs, undergo rapid development. Each disc everts and elongates, with the central portion of the disc becoming the distal part of whichever appendage it is forming: the wing, leg, antenna, etc. During the larval stage, the cells in the growing disc appear undifferentiated, but their developmental fate in the adult is already determined. The experiment that demonstrates this developmental commitment is to take an imaginal disc from a third instar larva, abo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dormancy
Dormancy is a period in an organism's Biological life cycle, life cycle when growth, development, and (in animals) physical activity are temporarily stopped. This minimizes metabolism, metabolic activity and therefore helps an organism to conserve energy. Dormancy tends to be closely associated with Ecosystem, environmental conditions. Organisms can synchronize entry to a dormant phase with their Ecosystem, environment through predictive or consequential means. Predictive dormancy occurs when an organism enters a dormant phase ''before'' the onset of adverse conditions. For example, photoperiod and decreasing temperature are used by many plants to predict the onset of winter. Consequential dormancy occurs when organisms enter a dormant phase ''after'' adverse conditions have arisen. This is commonly found in areas with an unpredictable climate. While very sudden changes in conditions may lead to a high mortality rate among animals relying on consequential dormancy, its use can be a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diapause
In animal dormancy, diapause is the delay in development in response to regular and recurring periods of adverse environmental conditions.Tauber, M.J., Tauber, C.A., Masaki, S. (1986) ''Seasonal Adaptations of Insects''. Oxford University Press It is a physiological state with very specific initiating and inhibiting conditions. The mechanism is a means of surviving predictable, unfavorable environmental conditions, such as temperature extremes, drought, or reduced food availability. Diapause is observed in all the life stages of arthropods, especially insects. Activity levels of diapausing stages can vary considerably among species. Diapause may occur in a completely immobile stage, such as the pupae and eggs, or it may occur in very active stages that undergo extensive migrations, such as the adult monarch butterfly, ''Danaus plexippus''. In cases where the insect remains active, feeding is reduced and reproductive development is slowed or halted. Embryonic diapause, a somewhat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperate
In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout the year and more distinct seasonal changes compared to tropical climates, where such variations are often small; they usually differ only in the amount of precipitation. In temperate climates, not only do latitude, latitudinal positions influence temperature changes, but various sea currents, prevailing wind direction, continentality (how large a landmass is) and altitude also shape temperate climates. The Köppen climate classification defines a climate as "temperate" C, when the mean temperature is above but below in the coldest month to account for the persistence of frost. However, some adaptations of Köppen set the minimum at . Continental climate, Continental climates are classified as D and considered to be varie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropics
The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's axial tilt; the width of the tropics (in latitude) is twice the tilt. The tropics are also referred to as the tropical zone and the torrid zone (see geographical zone). Due to the overhead sun, the tropics receive the most solar energy over the course of the year, and consequently have the highest temperatures on the planet. Even when not directly overhead, the sun is still close to overhead throughout the year, therefore the tropics also have the lowest seasonal variation on the planet; "winter" and "summer" lose their temperature contrast. Instead, seasons are more commonly divided by precipitation variations than by temperature variations. The tropics maintain wide diversity of local climates, such as rain forests, monsoons, sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dry Season
The dry season is a yearly period of low rainfall, especially in the tropics. The weather in the tropics is dominated by the tropical rain belt, which moves from the northern to the southern tropics and back over the course of the year. The temperate counterpart to the tropical dry season is summer or winter. Rain belt The tropical rain belt lies in the southern hemisphere roughly from November to March; during that time the northern tropics have a dry season with sparser precipitation, and days are typically sunny throughout. From May to September, the rain belt lies in the northern hemisphere, and the southern tropics have their dry season. Under the Köppen climate classification, for tropical climates, a dry season month is defined as a month when average precipitation is below . The rain belt reaches roughly as far north as the Tropic of Cancer and as far south as the Tropic of Capricorn. Near these latitudes, there is one wet season and one dry season annually. At the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papilio Dardanus Emerging
''Papilio'' is a genus in the swallowtail butterfly family, Papilionidae, as well as the only representative of the tribe Papilionini. The word ''papilio'' is Latin for butterfly. It includes the common yellow swallowtail ('' Papilio machaon''), which is widespread in the Northern Hemisphere and the type species of the genus, as well as a number of other well-known North American species such as the western tiger swallowtail (''Papilio rutulus''). Familiar species elsewhere in the world include the Mormons (''Papilio polytes'', '' Papilio polymnestor'', '' Papilio memnon'', and '' Papilio deiphobus'') in Asia, the orchard and Ulysses swallowtails in Australia ('' Papilio aegeus'', '' Papilio ulysses'', respectively) and the citrus swallowtail of Africa ('' Papilio demodocus''). Older classifications of the swallowtails tended to use many rather small genera. More recent classifications have been more conservative, and as a result a number of former genera are now absorbed within ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
