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Castanopsis Tonkinensis
''Castanopsis'', commonly called chinquapin or chinkapin, is a genus of evergreen trees belonging to the beech family, Fagaceae. The genus contains about 140 species, which are today restricted to tropical and subtropical eastern Asia. A total of 58 species are native to China, with 30 endemic; the other species occur further south, through Indochina to Indonesia and the Philippines, mountainous areas of Taiwan, and also in Japan. The English name chinkapin is shared with other related plants, including the golden chinkapins of the Pacific United States, which are sometimes included within ''Castanopsis'' but are more often considered a separate but very closely related genus, ''Chrysolepis''. They show many characters typical of Fagaceae. They are at least large shrubs but some species grow into sizeable trees. Their leaves are usually tough and much sclerotized and have a well-developed cuticula. Their flowers are unisexual, and the male ones are borne in erect ...
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Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ...
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Chrysolepis
''Chrysolepis'' is a small genus of plants in the family Fagaceae, endemic to the western United States. Its two species have the common name chinquapin. The genus occurs from western Washington south to the Transverse Ranges in Southern California, and east into Nevada. Description ''Chrysolepis'' are evergreen trees and shrubs with simple, entire (untoothed) leaves with a dense layer of golden scales on the underside and a thinner layer on the upper side; the leaves persist for 3–4 years before falling. The fruit is a densely spiny cupule containing 1–3 sweet, edible nuts, eaten by the indigenous peoples. The fruit also provides food for chipmunks and squirrels. ''Chrysolepis'' is related to the subtropical southeast Asian genus ''Castanopsis'' (in which it was formerly included), but differs in the nuts being triangular and fully enclosed in a sectioned cupule, and in having bisexual catkins. ''Chrysolepis'' also differs from another allied genus ''Castanea'' (chestnut ...
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Keystone Species
A keystone species is a species which has a disproportionately large effect on its natural environment relative to its abundance, a concept introduced in 1969 by the zoologist Robert T. Paine. Keystone species play a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and numbers of various other species in the community. Without keystone species, the ecosystem would be dramatically different or cease to exist altogether. Some keystone species, such as the wolf, are also apex predators. The role that a keystone species plays in its ecosystem is analogous to the role of a keystone in an arch. While the keystone is under the least pressure of any of the stones in an arch, the arch still collapses without it. Similarly, an ecosystem may experience a dramatic shift if a keystone species is removed, even though that species was a small part of the ecosystem by measures of biomass o ...
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Habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and light intensity. Biotic factors will include the availability of food and the presence or absence of predators. Every species has particular habitat requirements, with habitat generalist species able to thrive in a wide array of environmental conditions while habitat specialist species requiring a very limited set of factors to survive. The habitat of a species is not necessarily found in a geographical area, it can be the interior ...
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Acorn
The acorn, or oaknut, is the nut of the oaks and their close relatives (genera ''Quercus'' and '' Lithocarpus'', in the family Fagaceae). It usually contains one seed (occasionally two seeds), enclosed in a tough, leathery shell, and borne in a cup-shaped cupule. Acorns are long and on the fat side. Acorns take between 5 and 24 months (depending on the species) to mature; see the list of ''Quercus'' species for details of oak classification, in which acorn morphology and phenology are important factors. Etymology The word ''acorn'' (earlier ''akerne'', and ''acharn'') is related to the Gothic name ''akran'', which had the sense of "fruit of the unenclosed land". The word was applied to the most important forest produce, that of the oak. Chaucer spoke of "achornes of okes" in the 14th century. By degrees, popular etymology connected the word both with "corn" and "oak-horn", and the spelling changed accordingly. The current spelling (emerged 15c.-16c.), derives from asso ...
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Nut (fruit)
A nut is a fruit consisting of a hard or tough nutshell protecting a kernel which is usually edible. In general usage and in a culinary sense, a wide variety of dry seeds are called nuts, but in a botanical context "nut" implies that the shell does not open to release the seed (indehiscent). Most seeds come from fruits that naturally free themselves from the shell, but this is not the case in nuts such as hazelnuts, chestnuts, and acorns, which have hard shell walls and originate from a compound ovary. The general and original usage of the term is less restrictive, and many nuts (in the culinary sense), such as almonds, pecans, pistachios, walnuts, and Brazil nuts, are not nuts in a botanical sense. Common usage of the term often refers to any hard-walled, edible kernel as a nut. Nuts are an energy-dense and nutrient-rich food source. Botanical definition A seed is the mature fertilised ovule of a plant; it consists of three parts, the embryo which will develop into a ne ...
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Calybium
The calybium and the cupule make up the accessory fruit of flowering plants in the family Fagaceae. These two parts derive from different flower components. The cupule holds and protects the fruit during its growth and maturation. In some genera (e.g. ''Lithocarpus, Quercus''), it only partly encloses the single nut, while in others (e.g. ''Castanea, Fagus''), it fully encloses the two or more nuts, and splits open at maturity into four valves to release the nuts. It is derived from the vegetative part of the flower (its attachment to the rest of the plant). It is covered by numerous scales. In some (e.g. ''Castanea''), the scales are developed into sharp spines, giving the nut protection from squirrels and other seed predators, while in others (e.g. most ''Quercus''), they are not. In ''Lithocarpus'', the cupule is very hard and bone-like in texture. The calybium (plural: calybia) is the fruit proper. It develops from an inferior ovary, meaning it is initially encased in the ...
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Fruit
In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particular have long propagated using the movements of humans and animals in a symbiotic relationship that is the means for seed dispersal for the one group and nutrition for the other; in fact, humans and many animals have become dependent on fruits as a source of food. Consequently, fruits account for a substantial fraction of the world's agricultural output, and some (such as the apple and the pomegranate) have acquired extensive cultural and symbolic meanings. In common language usage, "fruit" normally means the seed-associated fleshy structures (or produce) of plants that typically are sweet or sour and edible in the raw state, such as apples, bananas, grapes, lemons, oranges, and strawberries. In botanical usage, the term "fruit" also i ...
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Seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosperm plants. Seeds are the product of the ripened ovule, after the embryo sac is fertilized by sperm from pollen, forming a zygote. The embryo within a seed develops from the zygote, and grows within the mother plant to a certain size before growth is halted. The seed coat arises from the integuments of the ovule. Seeds have been an important development in the reproduction and success of vegetable gymnosperm and angiosperm plants, relative to more primitive plants such as ferns, mosses and liverworts, which do not have seeds and use water-dependent means to propagate themselves. Seed plants now dominate biological niches on land, from forests to grasslands both in hot and cold climates. The term "seed" also has a general me ...
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Epigynous
In the flowering plants, an ovary is a part of the female reproductive organ of the flower or gynoecium. Specifically, it is the part of the pistil which holds the ovule(s) and is located above or below or at the point of connection with the base of the petals and sepals. The pistil may be made up of one carpel or of several fused carpels (e.g. dicarpel or tricarpel), and therefore the ovary can contain part of one carpel or parts of several fused carpels. Above the ovary is the Style (botany), style and the stigma, which is where the pollen lands and germinates to grow down through the style to the ovary, and, for each individual pollen grain, to fertilize one individual ovule. Some wind pollinated flowers have much reduced and modified ovaries. Fruits A fruit is the mature, ripened ovary of a flower following double fertilization in an angiosperm. Because gymnosperms do not have an ovary but reproduce through double fertilization of unprotected ovules, they produce naked s ...
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Catkin
A catkin or ament is a slim, cylindrical flower cluster (a spike), with inconspicuous or no petals, usually wind-pollinated (anemophilous) but sometimes insect-pollinated (as in ''Salix''). They contain many, usually unisexual flowers, arranged closely along a central stem that is often drooping. They are found in many plant families, including Betulaceae, Fagaceae, Moraceae, and Salicaceae. Occurrence Catkin-bearing plants include many trees or shrubs such as birch, willow, aspen, hickory, sweet chestnut, and sweetfern (''Comptonia''). In many of these plants, only the male flowers form catkins, and the female flowers are single ( hazel, oak), a cone (alder), or other types (mulberry). In other plants (such as poplar), both male and female flowers are borne in catkins. In Britain, they can be seen in January or February, when many trees are bare for winter. They can even occur in December. Evolution For some time, catkins were believed to be a key synapomorphy among the ...
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Unisexual
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is biparental reproduction. Dioecy has costs, since only about half the population directly produces offspring. It is one method for excluding self-fertilization and promoting allogamy (outcrossing), and thus tends to reduce the expression of recessive deleterious mutations present in a population. Plants have several other methods of preventing self-fertilization including, for example, dichogamy, herkogamy, and self-incompatibility. Dioecy is a dimorphic sexual system, alongside gynodioecy and androdioecy. In zoology In zoology, dioecious species may be opposed to hermaphroditic species, meaning that an individual is either male or female, in which case the synonym gonochory is more often used. Most animal species are dioecious (gon ...
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