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Velutina Velutina
''Velutina velutina'', common name the velvet shell, is a species of small sea snail with a transparent shell, a marine gastropod mollusk in the family Velutinidae. Description The maximum body size is from 15 to 50 mm. The maximum recorded shell length is 27.5 mm.Welch J. J. (2010). "The "Island Rule" and Deep-Sea Gastropods: Re-Examining the Evidence". '' PLoS ONE'' 5(1): e8776. . Distribution The distribution of ''Velutina velutina'' is circumboreal. The range of ''Velutina velutina'' include: 72.78°N to 42°N; 70°W to 0°W. Distribution of ''Velutina velutina'' include: * Greenland: West Greenland. * Canada: Labrador, Nova Scotia, New Brunswick * USA: Maine, Massachusetts, including Cobscook Bay Ecology The habitat of ''Velutina velutina'' include bathyal, infralittoral and circalittoral of the Gulf and estuary. Minimum recorded depth is 0 m. Maximum recorded depth is 183 m. ''Velutina velutina'' feeds on ascidians.Manfred Diehl (1956): ''Die Raubschneck ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Friedrich Müller
Otto Friedrich Müller, also known as Otto Friedrich Mueller (2 November 1730 – 26 December 1784) was a Danish naturalist and scientific illustrator. Biography Müller was born in Copenhagen. He was educated for the church, became tutor to a young nobleman, and after several years' travel with him, settled in Copenhagen in 1767, and married a lady of wealth. His first important works, ''Fauna Insectorum Friedrichsdaliana'' (Leipzig, 1764), and ''Flora Friedrichsdaliana'' (Strasbourg, 1767), giving accounts of the insects and flora of the estate of Frederiksdal, near Copenhagen, recommended him to Frederick V of Denmark, by whom he was employed to continue the ''Flora Danica'' a comprehensive atlas of the flora of Denmark. Müller added two volumes to the three published by Georg Christian Oeder since 1761. The study of invertebrates began to occupy his attention almost exclusively, and in 1771 he produced a work in German on “Certain Worms inhabiting Fresh and Salt Water, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenland
Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland is the world's largest island. It is one of three constituent countries that form the Kingdom of Denmark, along with Denmark and the Faroe Islands; the citizens of these countries are all citizens of Denmark and the European Union. Greenland's capital is Nuuk. Though a part of the continent of North America, Greenland has been politically and culturally associated with Europe (specifically Norway and Denmark, the colonial powers) for more than a millennium, beginning in 986.The Fate of Greenland's Vikings , by Dale Mackenzie Brown, ''Archaeological Institute of America'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-fertilization
Autogamy, or self-fertilization, refers to the fusion of two gametes that come from one individual. Autogamy is predominantly observed in the form of self-pollination, a reproductive mechanism employed by many flowering plants. However, species of protists have also been observed using autogamy as a means of reproduction. Flowering plants engage in autogamy regularly, while the protists that engage in autogamy only do so in stressful environments. Occurrence Protists ''Paramecium aurelia'' ''Paramecium aurelia'' is the most commonly studied protozoan for autogamy. Similar to other unicellular organisms, ''Paramecium aurelia'' typically reproduce asexually via binary fission or sexually via cross-fertilization. However, studies have shown that when put under nutritional stress, ''Paramecium aurelia'' will undergo meiosis and subsequent fusion of gametic-like nuclei. This process, defined as hemixis, a chromosomal rearrangement process, takes place in a number of steps. First, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermaphrodite
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrates) do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male. For example, the great majority of tunicata, tunicates, pulmonate molluscs, opisthobranch, earthworms, and slugs are hermaphrodites. Hermaphroditism is also found in some fish species and to a lesser degree in other vertebrates. Most plants are also hermaphrodites. Animal species having different sexes, male and female, are called Gonochorism, gonochoric, which is the opposite of hermaphrodite. There are also species where hermaphrodites exist alongside males (called androdioecy) or alongside females (called gynodioecy), or all three exist in the same species ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascidians
Ascidiacea, commonly known as the ascidians, tunicates (in part), and sea squirts (in part), is a polyphyletic class in the subphylum Tunicata of sac-like marine invertebrate filter feeders. Ascidians are characterized by a tough outer "tunic" made of a polysaccharide. Ascidians are found all over the world, usually in shallow water with salinities over 2.5%. While members of the Thaliacea and Larvacea (Appendicularia) swim freely like plankton, sea squirts are sessile animals after their larval phase: they then remain firmly attached to their substratum, such as rocks and shells. There are 2,300 species of ascidians and three main types: solitary ascidians, social ascidians that form clumped communities by attaching at their bases, and compound ascidians that consist of many small individuals (each individual is called a zooid) forming colonies up to several meters in diameter. Sea squirts feed by taking in water through a tube, the oral siphon. The water enters the mouth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infralittoral
The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal areas that are permanently submerged — known as the ''foreshore'' — and the terms are often used interchangeably. However, the geographical meaning of ''littoral zone'' extends well beyond the intertidal zone to include all neritic waters within the bounds of continental shelves. Etymology The word ''littoral'' may be used both as a noun and as an adjective. It derives from the Latin noun ''litus, litoris'', meaning "shore". (The doubled ''t'' is a late-medieval innovation, and the word is sometimes seen in the more classical-looking spelling ''litoral''.) Description The term has no single definition. What is regarded as the full extent of the littoral zone, and the way the littoral zone is divided into subregions, varies in different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathyal
The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of below the ocean surface. It lies between the mesopelagic above, and the abyssopelagic below. The bathypelagic is known as the midnight zone because of the lack of sunlight; this feature does not allow for photosynthesis-driven primary production, preventing growth of phytoplankton or aquatic plants. Although larger by volume than the photic zone, our knowledge of the bathypelagic zone remains limited by our ability to explore the deep ocean. Physical characteristics The bathypelagic zone is characterized by a nearly constant temperature of approximately and a salinity range of 33-35 g/kg. This region has little to no light, because sunlight does not reach this deep in the ocean and bioluminescence is limited. The hydrostatic pressure in this zone ranges 100-400 atmospheres (atm), due to the increase of 1 atm for every 10 m depth. It is beli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobscook Bay
Cobscook Bay is located in Washington County in the state of Maine. It opens into Passamaquoddy Bay, within the Bay of Fundy. Cobscook Bay is immediately south of the island city of Eastport, the main island of which (Moose Island) straddles the two bays. In the 1930s, Cobscook Bay was part of the aborted Passamaquoddy Bay Tidal Power Project (a.k.a., ''Quoddy Dam Project'') to generate electricity from its large tidal range. Geography Cobscook Bay is a large bay in Washington County, Maine that opens into Passamaquoddy Bay within the Bay of Fundy through a relatively narrow opening. It is about long and 10 wide and has a long, convoluted coastline with many islands. The mouth of the bay is bracketed by the island city of Eastport, which is principally on Moose Island, and by the town of Lubec. Other townships around the bay are Perry, Pembroke, Dennysville, Edmunds, and Tresscott. There are about 7,000 people living in the nine communities in the area, many of whom are fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Massachusetts
Massachusetts (Massachusett language, Massachusett: ''Muhsachuweesut [Massachusett writing systems, məhswatʃəwiːsət],'' English: , ), officially the Commonwealth of Massachusetts, is the most populous U.S. state, state in the New England region of the Northeastern United States. It borders on the Atlantic Ocean and Gulf of Maine to the east, Connecticut and Rhode Island to the south, New Hampshire and Vermont to the north, and New York (state), New York to the west. The state's capital and List of municipalities in Massachusetts, most populous city, as well as its cultural and financial center, is Boston. Massachusetts is also home to the urban area, urban core of Greater Boston, the largest metropolitan area in New England and a region profoundly influential upon American History of the United States, history, academia, and the Economy of the United States, research economy. Originally dependent on agriculture, fishing, and trade. Massachusetts was transformed into a manuf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maine
Maine () is a state in the New England and Northeastern regions of the United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Canadian provinces of New Brunswick and Quebec to the northeast and northwest, respectively. The largest state by total area in New England, Maine is the 12th-smallest by area, the 9th-least populous, the 13th-least densely populated, and the most rural of the 50 U.S. states. It is also the northeasternmost among the contiguous United States, the northernmost state east of the Great Lakes, the only state whose name consists of a single syllable, and the only state to border exactly one other U.S. state. Approximately half the area of Maine lies on each side of the 45th parallel north in latitude. The most populous city in Maine is Portland, while its capital is Augusta. Maine has traditionally been known for its jagged, rocky Atlantic Ocean and bayshore coastlines; smoothly contoured mountains; heavily f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Brunswick
New Brunswick (french: Nouveau-Brunswick, , locally ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. It is the only province with both English and French as its official languages. New Brunswick is bordered by Quebec to the north, Nova Scotia to the east, the Gulf of Saint Lawrence to the northeast, the Bay of Fundy to the southeast, and the U.S. state of Maine to the west. New Brunswick is about 83% forested and its northern half is occupied by the Appalachians. The province's climate is continental with snowy winters and temperate summers. New Brunswick has a surface area of and 775,610 inhabitants (2021 census). Atypically for Canada, only about half of the population lives in urban areas. New Brunswick's largest cities are Moncton and Saint John, while its capital is Fredericton. In 1969, New Brunswick passed the Official Languages Act which began recognizing French as an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
