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Sponge Reef
Sponge reefs are reefs produced by sea sponges. All modern sponge reefs are formed by hexactinellid sponges, which have an endoskeleton made of silica spicules and are often referred to as "glass sponges", while historically the non-spiculed, calcite-skeletoned archaeocyathid and stromatoporoid sponges were the primary reef-builders. Sponge reefs were once a dominant landscape in the Paleozoic and Mesozoic sea, but are now very rare, and found only in waters off the coast of North America's Pacific Northwest region, more specifically southern Alaska, British Columbia and Washington. Sponge reefs were reported in 2018 within the strait of Georgia and Howe sound close to Vancouver. Although still common in the late Jurassic period, reef-building sponges were believed to have gone extinct during or shortly after the Cretaceous period, until the existing reefs were discovered in Queen Charlotte sound in 1987–1988 – hence these sometimes being dubbed living fossils. L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haeckel Hexactinellae
Ernst Heinrich Philipp August Haeckel (; ; 16 February 1834 – 9 August 1919) was a German zoologist, naturalist, eugenicist, philosopher, physician, professor, marine biologist and artist. He discovered, described and named thousands of new species, mapped a genealogical tree relating all life forms and coined many terms in biology, including ''ecology'', ''phylum'', ''phylogeny'', ontogeny, and ''Protista.'' Haeckel promoted and popularised Charles Darwin's work in Germany and developed the debunked but influential recapitulation theory ("ontogeny recapitulates phylogeny"), wrongly claiming that an individual organism's biological development, or ontogeny, parallels and summarizes its species' evolutionary development, or phylogeny, using incorrectly drawn images of human embryonic development. Whether they were intentionally falsified, or drawn poorly by accident is a matter of debate. The published artwork of Haeckel includes over 100 detailed, multi-colour illustrations o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washington (state)
Washington, officially the State of Washington, is a U.S. state, state in the Pacific Northwest region of the United States. It is often referred to as Washington State to distinguish it from Washington, D.C., the national capital, both named after George Washington (the first President of the United States, U.S. president). Washington borders the Pacific Ocean to the west, Oregon to the south, Idaho to the east, and shares Canada–United States border, an international border with the Provinces and territories of Canada, Canadian province of British Columbia to the north. Olympia, Washington, Olympia is the List of capitals in the United States, state capital, and the most populous city is Seattle. Washington is the List of U.S. states and territories by area, 18th-largest state, with an area of , and the List of U.S. states and territories by population, 13th-most populous state, with a population of just less than 8 million. The majority of Washington's residents live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloud Sponge
The cloud sponge ''(Aphrocallistes vastus)'', also known as the quesadilla sponge, is a species of sea sponge in the class Hexactinellida. It is a deep-water reef-forming animal. The species was first described by F.E. Schulze in 1886. Description The cloud sponge takes the form of a large cup with an irregularly folded wall about thick. This is pierced by many pores about wide and covered by a thin dermal membrane. The skeletal elements form a lattice-like structure made up of fused spicules of silica. These mesh together and project into the adjoining canals. There is a fir-tree like concentration of spicules running through the body wall with the branches either having rounded or knobbly ends. The form of the sponge varies according to the location in which it is found. The quesadilla sponge's common name derives from a morphological variation first observed in the Olympic Coast National Marine Sanctuary. It often has a mitten-like structure or may be tall and cylindrical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexasterophora
Hexasterophora are a Class (biology), subclass of glass Sponge, sponges in the class Hexactinellida. Most living hexasterophorans can be divided into three orders: Lyssacinosida, Lychniscosida, and Sceptrulophora. Like other glass sponges, hexasterophorans have skeletons composed of overlapping six-rayed spicule (sponge), spicules. In addition, they can be characterized by the presence of hexasters, a type of microsclere (microscopic spicules) with six rays unfurling into multi-branched structures. A living sponge is commonly firmly attached by its base to a hard substrate (biology), substratum; less often rooted by the anchoring spicules and rarely inserted directly into the loose bottom sediments. The three orders are differentiated by the extent to which adjacent spicules have fused. The oldest order, without fused spicules, is Lyssacinosida (or Lyssacinosa), which appears in the Ordovician. The other two orders have fully fused their spicules into a framework of dictyonal st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syncytium
A syncytium (; : syncytia; from Greek: σύν ''syn'' "together" and κύτος ''kytos'' "box, i.e. cell") or symplasm is a multinucleate cell that can result from multiple cell fusions of uninuclear cells (i.e., cells with a single nucleus), in contrast to a coenocyte, which can result from multiple nuclear divisions without accompanying cytokinesis. The muscle cell that makes up animal skeletal muscle is a classic example of a syncytium cell. The term may also refer to cells interconnected by specialized membranes with gap junctions, as seen in the heart muscle cells and certain smooth muscle cells, which are synchronized electrically in an action potential. The field of embryogenesis uses the word ''syncytium'' to refer to the coenocytic blastoderm embryos of invertebrates, such as ''Drosophila melanogaster''. Physiological examples Protists In protists, syncytia can be found in some rhizarians (e.g., chlorarachniophytes, plasmodiophorids, haplosporidians) and acellul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Demersal
The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of the larger profundal zone. Being just above the ocean floor, the demersal zone is variable in depth and can be part of the photic zone where light can penetrate, and photosynthetic organisms grow, or the aphotic zone, which begins between depths of roughly and extends to the ocean depths, where no light penetrates. Fish The distinction between demersal species of fish and pelagic species is not always clear cut. The Atlantic cod (''Gadus morhua'') is a typical demersal fish, but can also be found in the open water column, and the Atlantic herring (''Clupea harengus'') is predominantly a pelagic species but forms large aggregations near the seabed when it spawns on banks of gravel. Two types of fish inhabit the demersal zone: those ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat
In ecology, habitat refers to the array of resources, 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 Biophysical environment, 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 Luminous intensity, light intensity. Biotic index, Biotic factors include the availability of food and the presence or absence of Predation, predators. Every species has particular habitat requirements, habitat generalist species are able to thrive in a wide array of environmental conditions while habitat specialist species require a very limited set of factors to survive. The habitat of a species is not necessarily found in a ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral Reef
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes sea anemones and jellyfish. Unlike sea anemones, corals secrete hard carbonate exoskeletons that support and protect the coral. Most reefs grow best in warm, shallow, clear, sunny and agitated water. Coral reefs first appeared 485 million years ago, at the dawn of the Early Ordovician, displacing the microbial and sponge reefs of the Cambrian. Sometimes called ''rainforests of the sea'', shallow coral reefs form some of Earth's most diverse ecosystems. They occupy less than 0.1% of the world's ocean area, about half the area of France, yet they provide a home for at least 25% of all marine species, including fish, mollusks, worms, crustaceans, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Living Fossil
A living fossil is a Deprecation, deprecated term for an extant taxon that phenotypically resembles related species known only from the fossil record. To be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade. Living fossils commonly are of species-poor lineages, but they need not be. While the body plan of a living fossil remains superficially similar, it is never the same species as the remote relatives it resembles, because genetic drift would inevitably change its chromosomal structure. Living fossils exhibit punctuated equilibrium, stasis (also called "bradytely") over geologically long time scales. Popular literature may wrongly claim that a "living fossil" has undergone no significant evolution since fossil times, with practically no molecular evolution or Morphology (biology), morphological changes. Scientific investigations have repeatedly discredited such claims. The minimal superficial changes to living foss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queen Charlotte Sound (Canada)
Queen Charlotte Sound () is a sound of the Pacific Ocean in British Columbia, Canada, between Vancouver Island in the south and Haida Gwaii in the north. It merges with Hecate Strait in the north and Queen Charlotte Strait in the south. Queen Charlotte Sound is part of the Inside Passage shipping route. It is part of the Haíɫzaqv Nation territory also known as the Heiltsuk Nation. Definition According to the BCGNIS, the northern boundary of Queen Charlotte Sound is defined as a line running from the southernmost point of Price Island to Cape St James on Kunghit Island, the southernmost point of Haida Gwaii. The western boundary is a line from Cape St James to Cape Scott at the north end of Vancouver Island. The southern boundary runs along the coast of Vancouver Island from Cape Scott to Cape Sutil, then to Cape Caution on the mainland. An older definition placed the northern boundary as a line from the southernmost point of Aristazabal Island to Cape St James. Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous Period
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 77.1 million years, it is the ninth and longest geological period of the entire Phanerozoic. The name is derived from the Latin , 'chalk', which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation . The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was largely ice-free, although there is some evidence of brief periods of glaciation during the cooler first half, and forests extended to the poles. Many of the dominant taxonomic groups present in modern times can be ultimately traced back to origins in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. The Jurassic constitutes the second and middle period of the Mesozoic, Mesozoic Era as well as the eighth period of the Phanerozoic, Phanerozoic Eon and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic magmatic province, Central Atlantic Magmatic Province (CAMP). The beginning of the Toarcian Age started around 183 million years ago and is marked by the Toarcian Oceanic Anoxic Event, a global episode of Anoxic event, oceanic anoxia, ocean acidification, and elevated global temperatures associated with extinctions, likely caused by the eruption of the Kar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
