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Whale

 Whale, common name for large, aquatic or marine mammals of order Cetacea, which inhabit all oceans.

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Thrips

Thrips, order Thysanoptera (Gk for "fringe-wings"), are among the smallest insects, being slender and usually less than 2 mm long.

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Acid Rain

Acid rain is the wet or dry deposition of acidic substances and their precursors on the Earth's surface. The ongoing industrialization of society has resulted in the increased release of acidic chemicals into the atmosphere.

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Tanager

The tanager (Thraupidae) is a family of small songbirds, possibly comprising as many as 413 species.

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Sturgeon

The sturgeon is a large, primitive, bony fish of class Actinopterygii, family Acipenseridae. The 4 genera and 24 species live in fresh and coastal waters of the Northern Hemisphere.

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Tungsten

Tungsten (W), also called Wolfram, lapis ponderosus or Heavy Stone, is a silver-grey metallic element with the highest melting point of any metal (3410° C). Tungsten has a high density, high strength at elevated temperatures and extreme hardness.

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Tunnels

Unlike other mountainous countries such as Switzerland, and despite its size, Canada is not distinguished by well-known tunnels.

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Shrimp

Shrimp are decapods ("10-footed") crustacean, differing from other decapods in being adapted for swimming, a fact reflected in the large, laterally compressed abdomen and well-developed pairs of swimming legs.

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Canadian Shield

The Canadian Shield refers to the exposed portion of the continental crust underlying the majority of North America. The crust, also known as the North American Craton, extends from northern Mexico to Greenland and consists of hard rocks at least 1 billion years old. With the exception of the Canadian Shield, the rocks of the North American Craton are buried deep within the continent and covered by soil and other material. At 5 million km2, the Shield makes up roughly 50 per cent of Canada’s land mass. Shaped like a horseshoe — or the shields carried during hand-to-hand combat — the Canadian Shield extends from Labrador in the east to include nearly all of Québec, much of Ontario and Manitoba, the northern portion of Saskatchewan, the northeast corner of Alberta, much of the Northwest Territories and Nunavut and into the Arctic Archipelago. (It also reaches into parts of the United States, in New York, Wisconsin and Minnesota.) While at times a barrier to settlement, the Shield has also yielded great resources, including minerals, coniferous forests and the capacity for hydroelectric developments.

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Sea Urchin

Sea Urchin, radially symmetrical marine invertebrate. Sea urchins and near relatives, the sand dollars and heart urchins, belong to class Echinoidea of phylum Echinodermata.

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Seabird

Seabirds are those bird species which spend long periods away from land and obtain all or most of their food from the sea while flying, swimming or diving, and occupy all of the world's oceans.

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Sponge

Sponge (Porifera), phylum of bottom-dwelling, attached, aquatic organisms which, as adults, generate vigorous water currents through their porous bodies by action of internal fields of microscopic flagella (whiplike structures).

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Spring

A spring is a point of natural, concentrated groundwater discharge from soil or rock.

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Starfish

Starfish, or sea star, is a common marine animal found from seashore to ocean depths; 1600 species are known worldwide.

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Sparrow

Sparrow is the name given to several unrelated groups of birds. Sparrows are classified in 3 families: Emberizidae, Estrildidae, and Passeridae.

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Spiraea

Spiraea is a genus of small shrubs of the family Rosaceae (rose). The genus consists of some 70-80 species, as well as many horticultural varieties of garden origin that have resulted from hybridization. Probably the most noteworthy of these hybrids is S.

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Squirrel

 Squirrel, common name for family (Sciuridae) of rodents, comprising 262 species, found in North and South America, Eurasia and Africa.

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Silica

Silica, or silicon dioxide (SiO2), occurs as the MINERAL quartz and is the most abundant mineral of the Earth's crust. It also occurs in the skeletal parts of some animals (eg, certain protozoa) and various plants.

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