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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] |
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] |
Butterflies
Butterflies are winged insects from the lepidopteran superfamily Papilionoidea, characterized by large, often brightly coloured wings that often fold together when at rest, and a conspicuous, fluttering flight. The oldest butterfly fossils have been dated to the Paleocene, about 56 million years ago, though molecular evidence suggests that they likely originated in the Cretaceous. Butterflies have a four-stage life cycle, and like other holometabolous insects they undergo complete metamorphosis. Winged adults lay eggs on the food plant on which their larvae, known as caterpillars, will feed. The caterpillars grow, sometimes very rapidly, and when fully developed, pupate in a chrysalis. When metamorphosis is complete, the pupal skin splits, the adult insect climbs out, expands its wings to dry, and flies off. Some butterflies, especially in the tropics, have several generations in a year, while others have a single generation, and a few in cold locations may take sever ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holometabolous
Holometabolism, also called complete metamorphosis, is a form of insect development which includes four life stages: egg, larva, pupa, and imago (or adult). Holometabolism is a synapomorphic trait of all insects in the clade Holometabola. Immature stages of holometabolous insects are very different from the mature stage. In some species the holometabolous life cycle prevents larvae from competing with adults because they inhabit different ecological niches. The morphology and behavior of each stage are adapted for different activities. For example, larval traits maximize feeding, growth, and development, while adult traits enable dispersal, mating, and egg laying. Some species of holometabolous insects protect and feed their offspring. Other insect developmental strategies include ametabolism and hemimetabolism. Developmental stages There are four general developmental stages, each with its own morphology and function. Egg The first stage of the insect life cycle is the egg, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase of their life cycle. A larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. In the case of smaller primitive arachnids, the larval stage differs by having three instead of four pairs of legs. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exuvia
In biology, exuviae are the remains of an exoskeleton and related structures that are left after ecdysozoans (including insects, crustaceans and arachnids) have molted. The exuviae of an animal can be important to biologists as they can often be used to identify the species of the animal and even its sex. As studying insects, crustaceans, or arachnids directly is not always possible, and because exuviae can be collected fairly easily, they can play an important part in helping to determine some general aspects of a species' overall life cycle such as distribution, sex ratio, production, and proof of breeding in a habitat. Exuviae have been suggested as a "gold standard" for insect monitoring. For instance, when monitoring dragonfly populations, the presence of exuviae of a species demonstrates that the species has completed its full life cycle from egg to adult in a habitat. However, it has also been suggested that the fact that exuviae can be hard to find could lead to an und ... [...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] |
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] |
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] |
