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Orange Sulphur
''Colias eurytheme'', the orange sulphur, also known as the alfalfa butterfly and in its larval stage as the alfalfa caterpillar, is a butterfly of the family Pieridae, where it belongs to the lowland group of " clouded yellows and sulphurs" subfamily Coliadinae. It is found throughout North America from southern Canada to Mexico. Other members of this lineage including the common or clouded sulphur ('' C. philodice'') and ''C. eriphyle'' and ''C. vitabunda'', which are often included in ''C. philodice'' as subspecies. Hybridization runs rampant between these, making phylogenetic analyses exclusively utilizing one type of data (especially mtDNA sequences) unreliable. Therefore, little more can be said about its relationships, except that it is perhaps closer to ''C. (p.) eriphyle'' than generally assumed, strengthening the view that the latter should be considered a valid species.Wheat, Christopher W. & Watt, Ward B. (2008). A mitochondrial-DNA-based phylogeny for some evolutiona ... [...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 Paris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alfalfa
Alfalfa () (''Medicago sativa''), also called lucerne, is a perennial flowering plant in the legume family Fabaceae. It is cultivated as an important forage crop in many countries around the world. It is used for grazing, hay, and silage, as well as a green manure and cover crop. The name alfalfa is used in North America. The name lucerne is the more commonly used name in the United Kingdom, South Africa, Australia, and New Zealand. The plant superficially resembles clover (a cousin in the same family), especially while young, when trifoliate leaves comprising round leaflets predominate. Later in maturity, leaflets are elongated. It has clusters of small purple flowers followed by fruits spiralled in 2 to 3 turns containing 10–20 seeds. Alfalfa is native to warmer temperate climates. It has been cultivated as livestock fodder since at least the era of the ancient Greeks and Romans. Etymology The word ''alfalfa'' is a Spanish modification of the Arabic word ''al-faṣfa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mate Selection
Mate choice is one of the primary mechanisms under which evolution can occur. It is characterized by a "selective response by animals to particular stimuli" which can be observed as behavior.Bateson, Paul Patrick Gordon. "Mate Choice." Mate Choice, Cambridge University Press, 1985 In other words, before an animal engages with a potential mate, they first evaluate various aspects of that mate which are indicative of quality—such as the resources or phenotypes they have—and evaluate whether or not those particular trait(s) are somehow beneficial to them. The evaluation will then incur a response of some sort. These mechanisms are a part of evolutionary change because they operate in a way that causes the qualities that are desired in a mate to be more frequently passed on to each generation over time. For example, if female peacocks desire mates who have a colourful plumage, then this trait will increase in frequency over time as male peacocks with a colourful plumage will have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Courtship
Courtship is the period wherein some couples get to know each other prior to a possible marriage. Courtship traditionally may begin after a betrothal and may conclude with the celebration of marriage. A courtship may be an informal and private matter between two people or may be a public affair, or a formal arrangement with family approval. Traditionally, in the case of a formal engagement, it is the role of a male to actively "court" or "woo" a female, thus encouraging her to understand him and her receptiveness to a marriage proposal. Duration The average duration of courtship varies considerably throughout the world. Furthermore, there is vast individual variation between couples. Courtship may be completely omitted, as in cases of some arranged marriages where the couple do not meet before the wedding. In the United Kingdom, a poll of 3,000 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sex-limited Genes
Sex-limited genes are genes that are present in both sexes of sexually reproducing species but are expressed in only one sex and have no penetrance, or are simply 'turned off' in the other. In other words, sex-limited genes cause the two sexes to show different traits or phenotypes, despite having the same genotype. This term is restricted to autosomal traits, and should not be confused with sex-linked characteristics, which have to do with genetic differences on the sex chromosomes (see sex-determination system). Sex-limited genes are also distinguished frosex-influencedgenes, where the same gene will show differential expression in each sex. Sex-influenced genes commonly show a dominant/recessive relationship, where the same gene will have a dominant effect in one sex and a recessive effect in the other (for example, male pattern baldness). However, the resulting phenotypes caused by sex-limited genes are present in only one sex and can be seen prominently in various species t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pheromones
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavior of the receiving individuals. There are ''alarm pheromones'', ''food trail pheromones'', ''sex pheromones'', and many others that affect behavior or physiology. Pheromones are used by many organisms, from basic unicellular prokaryotes to complex multicellular eukaryotes. Their use among insects has been particularly well documented. In addition, some vertebrates, plants and ciliates communicate by using pheromones. The ecological functions and evolution of pheromones are a major topic of research in the field of chemical ecology. Background The portmanteau word "pheromone" was coined by Peter Karlson and Martin Lüscher in 1959, based on the Greek φερω ''pheroo'' ('I carry') and ὁρμων ''hormon'' ('stimulating'). Pheromones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X Chromosome
The X chromosome is one of the two sex-determining chromosomes (allosomes) in many organisms, including mammals (the other is the Y chromosome), and is found in both males and females. It is a part of the XY sex-determination system and XO sex-determination system. The X chromosome was named for its unique properties by early researchers, which resulted in the naming of its counterpart Y chromosome, for the next letter in the alphabet, following its subsequent discovery. Discovery It was first noted that the X chromosome was special in 1890 by Hermann Henking in Leipzig. Henking was studying the testicles of ''Pyrrhocoris'' and noticed that one chromosome did not take part in meiosis. Chromosomes are so named because of their ability to take up staining (''chroma'' in Greek means ''color''). Although the X chromosome could be stained just as well as the others, Henking was unsure whether it was a different class of object and consequently named it ''X element'', which later be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genes
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromaticity
Chromaticity is an objective specification of the quality of a color regardless of its luminance. Chromaticity consists of two independent parameters, often specified as hue (h) and colorfulness (s), where the latter is alternatively called saturation, chroma, intensity, or excitation purity. This number of parameters follows from trichromacy of vision of most humans, which is assumed by most models in color science. Quantitative description In color science, the white point of an illuminant or of a display is a neutral reference characterized by a chromaticity; all other chromaticities may be defined in relation to this reference using polar coordinates. The ''hue'' is the angular component, and the ''purity'' is the radial component, normalized by the maximum radius for that hue. Purity is roughly equivalent to the term "saturation" in the HSV color model. The property "hue" is as used in general color theory and in specific color models such as HSV and HSL color spaces, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterin
Pterin is a heterocyclic compound composed of a pteridine ring system, with a "keto group" (a lactam) and an amino group on positions 4 and 2 respectively. It is structurally related to the parent bicyclic heterocycle called pteridine. Pterins, as a group, are compounds related to pterin with additional substituents. Pterin itself is of no biological significance. Pterins were first discovered in the pigments of butterfly wings (hence the origin of their name, from the Greek ''pteron (πτερόν)'', wing) and perform many roles in coloration in the biological world. Chemistry Pterins exhibit a wide range of tautomerism in water, beyond what is assumed by just keto-enol tautomerism. For the unsubstituted pterin, at least five tautomers are commonly cited. For 6-methylpterin, seven tautomers are theoretically predicted to be important in solution. The pteridine ring system contains four nitrogen atoms, reducing its aromaticity to the point that it can be attacked by nucleo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultraviolet
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nanometer, nm (with a corresponding frequency around 30 Hertz, PHz) to 400 nm (750 Hertz, THz), shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack the energy to ionization, ionize atoms, it can cause chemical reactions and causes many substances to glow or fluorescence, fluoresce. Consequently, the chemical and biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules. Short-wave ultraviolet light damages DNA and sterilizes surf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nearctic Realm
The Nearctic realm is one of the eight biogeographic realms constituting the Earth's land surface. The Nearctic realm covers most of North America, including Greenland, Central Florida, and the highlands of Mexico. The parts of North America that are not in the Nearctic realm are Eastern Mexico, Southern Florida, coastal Central Florida, Central America, and the Caribbean islands, which, together with South America, are part of the Neotropical realm. Major ecological regions The World Wildlife Fund (WWF) divides the Nearctic into four bioregions, defined as "geographic clusters of ecoregions that may span several habitat types, but have strong biogeographic affinities, particularly at taxonomic levels higher than the species level (genus, family)." Canadian Shield The Canadian Shield bioregion extends across the northern portion of the continent, from the Aleutian Islands to Newfoundland. It includes the Nearctic's Arctic Tundra and Boreal forest ecoregions. In terms of flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
