Firs
Firs (''Abies'') are a genus of 48–56 species of evergreen coniferous trees in the family Pinaceae. They are found on mountains throughout much of North and Central America, Europe, Asia, and North Africa. The genus is most closely related to ''Cedrus'' (cedar). The genus name is derived from the Latin "to rise" in reference to the height of its species. The common English name originates with the Old Norse, fyri, or the Old Danish, fyr. They are large trees, reaching heights of tall with trunk diameters of when mature. Firs can be distinguished from other members of the pine family by the way in which their needle-like leaves are attached singly to the branches with a base resembling a suction cup, and by their cones, which, like those of true cedars, stand upright on the branches like candles and disintegrate at maturity. Identification of the different species is based on the size and arrangement of the leaves, the size and shape of the cones, and whether the bract scal ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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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 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Holocene
The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together form the Quaternary period. The Holocene has been identified with the current warm period, known as MIS 1. It is considered by some to be an interglacial period within the Pleistocene Epoch, called the Flandrian interglacial.Oxford University Press – Why Geography Matters: More Than Ever (book) – "Holocene Humanity" section https://books.google.com/books?id=7P0_sWIcBNsC The Holocene corresponds with the rapid proliferation, growth and impacts of the human species worldwide, including all of its written history, technological revolutions, development of major civilizations, and overall significant transition towards urban living in the present. The human impact on modern-era Earth and its ecosystems may be considered of global si ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia and it is located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. Comprising the westernmost peninsulas of Eurasia, it shares the continental landmass of Afro-Eurasia with both Africa and Asia. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south and Asia to the east. Europe is commonly considered to be Boundaries between the continents of Earth#Asia and Europe, separated from Asia by the drainage divide, watershed of the Ural Mountains, the Ural (river), Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea and the waterways of the Turkish Straits. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and E ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthesis, photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf but in some species, including the mature foliage of ''Eucalyptus'', palisade mesophyll is present on both sides and the leaves are said to be isobilateral. Most leaves are flattened and have distinct upper (Glossary of botanical terms#adaxial, adaxial) and lower (Glossary of botanical terms#abaxial, abaxial) surfaces that differ in color, hairiness, the number of stomata (pores that intake and output gases), the amount and structure of epicuticular wax and other features. Leaves are mostly green in color due ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees. Trees are not a taxonomic group but include a variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some reaching several thousand years old. Trees have been in existence for 370 million years. It is estimated that there are some three trillion mature trees in the world. A tree typically has many secondary branches supported clear of the ground by the trunk. This trunk typically ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the west and south by the Pacific Ocean. Because it is on the North American Plate, North American Tectonic Plate, Greenland is included as a part of North America geographically. North America covers an area of about , about 16.5% of Earth's land area and about 4.8% of its total surface. North America is the third-largest continent by area, following Asia and Africa, and the list of continents and continental subregions by population, fourth by population after Asia, Africa, and Europe. In 2013, its population was estimated at nearly 579 million people in List of sovereign states and dependent territories in North America, 23 independent states, or about 7.5% of the world's population. In Americas (terminology)#Human ge ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pinaceae
The Pinaceae, or pine family, are conifer trees or shrubs, including many of the well-known conifers of commercial importance such as Cedrus, cedars, firs, Tsuga, hemlocks, larches, pines and spruces. The family is included in the order Pinales, formerly known as Coniferales. Pinaceae are supported as monophyletic by their protein-type sieve cell plastids, pattern of proembryogeny, and lack of bioflavonoids. They are the largest extant conifer family in species diversity, with between 220 and 250 species (depending on Taxonomy (biology), taxonomic opinion) in 11 genera, and the second-largest (after Cupressaceae) in geographical range, found in most of the Northern Hemisphere, with the majority of the species in temperate climates, but ranging from subarctic to tropical. The family often forms the dominant component of Boreal forest, boreal, coastal, and montane forests. One species, ''Pinus merkusii'', grows just south of the equator in Southeast Asia. Major centre of diversity, c ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Stoma
In botany, a stoma (from Greek ''στόμα'', "mouth", plural "stomata"), also called a stomate (plural "stomates"), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is bordered by a pair of specialized parenchyma cells known as guard cells that are responsible for regulating the size of the stomatal opening. The term is usually used collectively to refer to the entire stomatal complex, consisting of the paired guard cells and the pore itself, which is referred to as the stomatal aperture. Air, containing oxygen, which is used in respiration, and carbon dioxide, which is used in photosynthesis, passes through stomata by gaseous diffusion. Water vapour diffuses through the stomata into the atmosphere in a process called transpiration. Stomata are present in the sporophyte generation of all land plant groups except liverworts. In vascular plants the number, size and distribution of stomata varies widely. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Conifer
Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class (biology), class, Pinopsida. All Neontology, extant conifers are perennial plant, perennial woody plants with secondary growth. The great majority are trees, though a few are shrubs. Examples include Cedrus, cedars, Pseudotsuga, Douglas-firs, Cupressaceae, cypresses, firs, junipers, Agathis, kauri, larches, pines, Tsuga, hemlocks, Sequoioideae, redwoods, spruces, and Taxaceae, yews.Campbell, Reece, "Phylum Coniferophyta". Biology. 7th. 2005. Print. P. 595 As of 1998, the division Pinophyta was estimated to contain eight families, 68 genera, and 629 living species. Although the total number of species is relatively small, conifers are ecology, ecologically important. They are the dominant plants over large areas of land, most ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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North Africa
North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in the west, to Egypt's Suez Canal. Varying sources limit it to the countries of Algeria, Libya, Morocco, and Tunisia, a region that was known by the French during colonial times as "''Afrique du Nord''" and is known by Arabs as the Maghreb ("West", ''The western part of Arab World''). The United Nations definition includes Morocco, Algeria, Tunisia, Libya, Egypt, Sudan, and the Western Sahara, the territory disputed between Morocco and the Sahrawi Republic. The African Union definition includes the Western Sahara and Mauritania but not Sudan. When used in the term Middle East and North Africa (MENA), it often refers only to the countries of the Maghreb. North Africa includes the Spanish cities of Ceuta and Melilla, and plazas de s ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Central America
Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. Central America consists of eight countries: Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama. Within Central America is the Mesoamerican biodiversity hotspot, which extends from northern Guatemala to central Panama. Due to the presence of several active geologic faults and the Central America Volcanic Arc, there is a high amount of seismic activity in the region, such as volcanic eruptions and earthquakes which has resulted in death, injury, and property damage. In the pre-Columbian era, Central America was inhabited by the indigenous peoples of Mesoamerica to the north and west and the Isthmo-Colombian peoples to the south and east. Following the Spanish expedition of Christopher Columbus' ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |