An aquarium is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, amphibians, aquatic reptiles such as turtles, aquatic plants; the term "aquarium", coined by English naturalist Philip Henry Gosse, combines the Latin root aqua, meaning water, with the suffix -arium, meaning "a place for relating to". The aquarium principle was developed in 1850 by the chemist Robert Warington, who explained that plants added to water in a container would give off enough oxygen to support animals, so long as the numbers of animals did not grow too large; the aquarium craze was launched in early Victorian England by Gosse, who created and stocked the first public aquarium at the London Zoo in 1853, published the first manual, The Aquarium: An Unveiling of the Wonders of the Deep Sea in 1854. An aquarium is a water-filled tank. Small aquariums are kept in the home by hobbyists. There are larger public aquariums in many cities.
This kind of aquarium is other aquatic animals in large tanks. A large aquarium may have otters, turtles and other sea animals. Most aquarium tanks have plants. An aquarist owns fish or maintains an aquarium constructed of glass or high-strength acrylic. Cuboid aquaria are known as fish tanks or tanks, while bowl-shaped aquaria are known as fish bowls. Size can range from a small glass bowl, under a gallon in volume, to immense public aquaria of several thousand gallons. Specialized equipment maintains appropriate water quality and other characteristics suitable for the aquarium's residents. In 1369, the Hongwu Emperor of China established a porcelain company that produced large porcelain tubs for maintaining goldfish. Leonhard Baldner, who wrote Vogel-, Fisch- und Tierbuch in 1666, maintained weather loaches and newts, it is sometimes held that the aquarium was invented by the Romans, who are said to have kept sea barbels in marble-and-glass tanks, but this is unlikely to be true. In 1832, Jeanne Villepreux-Power, a pioneering French marine biologist, became the first person to create aquaria for experimenting with aquatic organisms.
In 1836, soon after his invention of the Wardian case, Dr. Nathaniel Bagshaw Ward proposed to use his tanks for tropical animals. In 1841 he did so, though only with toy fish. However, he soon housed real animals. In 1838, Félix Dujardin noted owning a saltwater aquarium. In 1846, Anne Thynne maintained stony corals and seaweed for three years, was credited as the creator of the first balanced marine aquarium in London. English chemist Robert Warington experimented with a 13-gallon container, which contained goldfish and snails, creating one of the first stable aquaria; the aquarium principle was developed by Warington, explaining that plants added to water in a container would give off enough oxygen to support animals, so long as their numbers do not grow too large. He published his findings in 1850 in the Chemical Society's journal; the keeping of fish in an aquarium spread quickly. In the United Kingdom, it became popular after ornate aquaria in cast-iron frames were featured at the Great Exhibition of 1851.
In 1853, the aquarium craze was launched in England by Philip Henry Gosse who created and stocked the first public aquarium in the London Zoo which came to be known as the Fish House. Gosse coined the word "aquarium", opting for this term in 1854 in his book The Aquarium: An Unveiling of the Wonders of the Deep Sea. In this book, Gosse discussed saltwater aquaria. In the 1850s, the aquarium became a fad in the United Kingdom. Tank designs and techniques for maintaining water quality were developed by Warington cooperating with Gosse until his critical review of the tank water composition. Edward Edwards developed these glass-fronted aquaria in his 1858 patent for a "dark-water-chamber slope-back tank", with water circulating to a reservoir beneath. Germans soon rivaled the British in their interest. In 1854, an anonymous author had two articles published about the saltwater aquaria of the United Kingdom: Die Gartenlaube entitled Der Ocean auf dem Tische. However, in 1856, Der See im Glase was published, discussing freshwater aquaria, which were much easier to maintain in landlocked areas.
In 1862 William Alford Lloyd bankrupt because of the craze in England being over, moved to Grindel Dammthor, Hamburg, to supervise the installation of the circulating system and tanks at the Hamburg Aquarium. During the 1870s, some of the first aquarist societies were appearing in Germany; the United States soon followed. Published in 1858, Henry D. Butler's The Family Aquarium was one of the first books written in the United States about the aquarium. According to the July issue of The North American Review of the same year, William Stimson may have owned some of the first functional aquaria, had as many as seven or eight; the first aquarist society in the United States was founded in New York City in 1893, followed by others. The New York Aquarium Journal, first published in October 1876, is considered to be the world's first aquarium magazine. In the Victorian era in the United Kingdom, a common design for the home aquarium was a glass front with the other sides made of wood; the bottom would be heated from below.
More advanced systems soon began to be introduced, along with tanks of
The Xingu River is a 1,640 km river in north Brazil. It is a southeast tributary of the Amazon River and one of the largest clearwater rivers in the Amazon basin, accounting for about 5% of its water; the first Indigenous Park in Brazil was created in the river basin by the Brazilian government in the early 1960s. This park marks the first indigenous territory recognized by the Brazilian government and it was the world's largest indigenous preserve on the date of its creation. Fourteen tribes live within Xingu Indigenous Park, surviving on natural resources and extracting from the river most of what they need for food and water; the Brazilian government is building the Belo Monte Dam, which will be the world's third-largest hydroelectric dam, on the Lower Xingu. Construction of this dam is under legal challenge by environment and indigenous groups, who assert the dam would have negative environmental and social impacts along with reducing the flow by up to 80% along a 100 km stretch known as the Volta Grande.
The river flow in this stretch is complex and includes major sections of rapids. More than 450 fish species have been documented in the Xingu River Basin and it is estimated that the total is around 600 fish species, including many endemics. At least 193 fish species living in rapids are known from the lower Xingu, at least 26 of these are endemic. From 2008 to 2018 alone, 24 new fish species have been described from the river. Many species are threatened by the dam, which will alter the flow in the Volta Grande rapids. In the Upper Xingu region was a self-organized pre-Columbian anthropogenic landscape, including deposits of fertile agricultural terra preta, black soil in Portuguese, with a network of roads and polities each of which covered about 250 square kilometers. Near the source of Xingu River is Culuene River, a 600 km tributary; the name is the title of a humorous Edith Wharton short story from 1911. "Xingu" is the title of a song on a 1999 album by Ozric Tentacles. The river is honoured in the album Aguas da Amazonia.
A beer produced near the river is sold in the international market under the name "Xingu". In the novel Relic by Douglas Preston and Lincoln Child, the Xingu River is the location of the doomed Whittlesey/Maxwell expedition responsible for discovering evidence of the lost Kothoga tribe and their savage god Mbwun, it is the name of a 2011 Brazilian movie, directed by famous Brazilian film-maker Cao Hamburger. The movie tells the story of the Villas-Bôas brothers 1943 expedition to the region, which led to the creation of the indigenous reserve twenty years later. Percy Fawcett Aloysius Pendergast Xingu National Park Xingu peoples Cowell, Adrian. 1973. The Tribe that Hides from Man; the Bodely Head, London. Original text from 1911 Encyclopædia Britannica Heinsdijk and Ricardo Lemos Fróes. Description of Forest-Types on "Terra Firme" between the Rio Tapajós and the Rio Xingú in the Amazon Valley. 1956. Sipes, Ernest "Brazilian Indians: what FUNAI Won't Tell YOU". 2002. Brazilian Indians: What FUNAI Won't Tell You Xingu on IMDb
The phenotype of an organism is the composite of the organism's observable characteristics or traits, including its morphology or physical form and structure. An organism's phenotype results from two basic factors: the expression of an organism's genetic code, or its genotype, the influence of environmental factors, which may interact, further affecting phenotype; when two or more different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented polymorphism is Labrador Retriever coloring. Richard Dawkins in 1978 and again in his 1982 book The Extended Phenotype suggested that bird nests and other built structures such as caddis fly larvae cases and beaver dams can be considered as "extended phenotypes"; the genotype-phenotype distinction was proposed by Wilhelm Johannsen in 1911 to make clear the difference between an organism's heredity and what that heredity produces. The distinction is similar to that proposed by August Weismann, who distinguished between germ plasm and somatic cells.
The genotype-phenotype distinction should not be confused with Francis Crick's central dogma of molecular biology, a statement about the directionality of molecular sequential information flowing from DNA to protein, not the reverse. The term "phenotype" has sometimes been incorrectly used as a shorthand for phenotypic difference from wild type, bringing the absurd statement that a mutation has no phenotype. Despite its straightforward definition, the concept of the phenotype has hidden subtleties, it may seem that anything dependent on the genotype is a phenotype, including molecules such as RNA and proteins. Most molecules and structures coded by the genetic material are not visible in the appearance of an organism, yet they are observable and are thus part of the phenotype, it may seem that this goes beyond the original intentions of the concept with its focus on the organism in itself. Either way, the term phenotype includes inherent traits or characteristics that are observable or traits that can be made visible by some technical procedure.
A notable extension to this idea is the presence of "organic molecules" or metabolites that are generated by organisms from chemical reactions of enzymes. Another extension adds behavior to the phenotype. Behavioral phenotypes include cognitive and behavioral patterns; some behavioral phenotypes may characterize psychiatric syndromes. Phenotypic variation is a fundamental prerequisite for evolution by natural selection, it is the living organism as a whole that contributes to the next generation, so natural selection affects the genetic structure of a population indirectly via the contribution of phenotypes. Without phenotypic variation, there would be no evolution by natural selection; the interaction between genotype and phenotype has been conceptualized by the following relationship: genotype + environment → phenotype A more nuanced version of the relationship is: genotype + environment + genotype & environment interactions → phenotype Genotypes have much flexibility in the modification and expression of phenotypes.
The plant Hieracium umbellatum is found growing in two different habitats in Sweden. One habitat is rocky, sea-side cliffs, where the plants are bushy with broad leaves and expanded inflorescences; these habitats alternate along the coast of Sweden and the habitat that the seeds of Hieracium umbellatum land in, determine the phenotype that grows. An example of random variation in Drosophila flies is the number of ommatidia, which may vary between left and right eyes in a single individual as much as they do between different genotypes overall, or between clones raised in different environments; the concept of phenotype can be extended to variations below the level of the gene that affect an organism's fitness. For example, silent mutations that do not change the corresponding amino acid sequence of a gene may change the frequency of guanine-cytosine base pairs; these base pairs have a higher thermal stability than adenine-thymine, a property that might convey, among organisms living in high-temperature environments, a selective advantage on variants enriched in GC content.
Richard Dawkins described a phenotype that included all effects that a gene has on its surroundings, including other organisms, as an extended phenotype, arguing that "An animal's behavior tends to maximize the survival of the genes'for' that behavior, whether or not those genes happen to be in the body of the particular animal performing it." For instance, an organism such as a beaver modifies its environment by building a beaver dam. When a bird feeds a brood parasite such as a cuckoo, it is unwittingly extending its phenotype.
Cichlids are fish from the family Cichlidae in the order Cichliformes. Cichlids were traditionally classed in a suborder, along with the wrasses, in the order Perciformes but molecular studies have contradicted this grouping; the closest living relatives of cichlids are the convict blennies and both families are classified in the 5th edition of Fishes of the World as the two families in the Cichliformes, part of the subseries Ovalentaria. This family is both diverse. At least 1,650 species have been scientifically described, making it one of the largest vertebrate families. New species are discovered annually, many species remain undescribed; the actual number of species is therefore unknown, with estimates varying between 2,000 and 3,000. Many cichlids tilapia, are important food fishes, while others, such as the Cichla species, are valued game fish; the family includes many popular freshwater aquarium fish kept by hobbyists, including the angelfish and discus. Cichlids have the largest number of endangered species among vertebrate families, most in the haplochromine group.
Cichlids are well known for having evolved into a large number of related but morphologically diverse species within large lakes Tanganyika, Victoria and Edward. Their diversity in the African Great Lakes is important for the study of speciation in evolution. Many cichlids introduced into waters outside of their natural range have become nuisances. All cichlids have some form of parental care for their eggs and fry; that parental care may come in the form of guarding the eggs and fry or it may come in the form of mouthbrooding. Cichlids span a wide range of body sizes, from species as small as 2.5 cm in length to much larger species approaching 1 m in length. As a group, cichlids exhibit a similar diversity of body shapes, ranging from laterally compressed species to species that are cylindrical and elongated. However, cichlids tend to be of medium size, ovate in shape, laterally compressed, similar to the North American sunfishes in morphology and ecology. Cichlids share a single key trait: the fusion of the lower pharyngeal bones into a single tooth-bearing structure.
A complex set of muscles allows the upper and lower pharyngeal bones to be used as a second set of jaws for processing food, allowing a division of labor between the "true jaws" and the "pharyngeal jaws". Cichlids are efficient and highly specialized feeders that capture and process a wide variety of food items; this is assumed to be one reason. The features that distinguish them from the other families in Labroidei include: A single nostril on each side of the forehead, instead of two No bony shelf below the orbit of the eye Division of the lateral line organ into two sections, one on the upper half of the flank and a second along the midline of the flank from about halfway along the body to the base of the tail A distinctively shaped otolith The small intestine's left-side exit from the stomach instead of its right side as in other Labroidei Kullander recognizes eight subfamilies of cichlids: the Astronotinae, Cichlinae, Geophaginae, Heterochromidinae, Pseudocrenilabrinae, Retroculinae.
A ninth subfamily, was recognized by Sparks and Smith. Cichlid taxonomy is still debated, classification of genera cannot yet be definitively given. A comprehensive system of assigning species to monophyletic genera is still lacking, there is not complete agreement on what genera should be recognized in this family; as an example of the classification problems, Kullander placed the African genus Heterochromis phylogenetically within Neotropical cichlids, although papers concluded otherwise. Other problems center upon the identity of the putative common ancestor for the Lake Victoria superflock, the ancestral lineages of Tanganyikan cichlids. Comparisons between a morphologically-based phylogeny and analyses of gene loci produce differences at the genus level. There remains a consensus. In cichlid taxonomy, dentition was used as a classifying characteristic. However, this was complicated by the fact that in many cichlids, tooth shape changes with age, due to wear, cannot be relied upon. Genome sequencing and other technologies transformed cichlid taxonomy.
Cichlids are one of the largest vertebrate families in the world. They are most diverse in South America. Africa alone is estimated to host at least 1,600 species. Central America and Mexico have about 120 species, as far north as the Rio Grande in southern Texas. Madagascar has its own distinctive species, only distantly related to those on the African mainland. Native cichlids are absent in Asia, except for 9 species in Israel and Syria, two in Iran, three in India and Sri Lanka. If disregarding Trinidad and Tobago, the three species from the genus Nandopsis are the only cichlids from the Antilles in the Caribbean Cuba and Hispaniola. Europe, Australia and North
Symphysodon aequifasciatus, the blue discus or brown discus, is a species of cichlid native to rivers of the eastern and central Amazon Basin downriver from the Purus arch. This discus is found in black-, clear- and whitewater, but its preference for lentic habitats such as floodplains and flooded forests means that the whitewater it inhabits contain little suspended material, it is restricted to water with a high temperature of 25–32 °C and a pH of 5.2–7.7. It reaches a length of up to 15.2 centimetres SL, but captives have been claimed to reach 23 cm. It is kept in aquariums; the taxonomy is disputed, but FishBase follows a review of the genus from 2006. In 2007 it was suggested that the correct scientific name of the blue/brown discus is S. haraldi, whereas S. aequifasciatus is the correct name for the green discus. In 2011 a study indicated that it should be split into three: Brown discus, blue discus and the Xingu group; the Xingu group lacks a scientific name, but it is possible that the correct name for the blue is S. haraldi.
This taxonomy where both S. haraldi and S. aequifasciatus are recognized as described valid species has been adopted by the Catalog of Fishes. Some hybridization occurs between the species recognized in the 2011 study and between the brown and Heckel discus, but overall they maintain their separate evolutionary trajectories
Animals are multicellular eukaryotic organisms that form the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, grow from a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from 8.5 millionths of a metre to 33.6 metres and have complex interactions with each other and their environments, forming intricate food webs. The category includes humans, but in colloquial use the term animal refers only to non-human animals; the study of non-human animals is known as zoology. Most living animal species are in the Bilateria, a clade whose members have a bilaterally symmetric body plan; the Bilateria include the protostomes—in which many groups of invertebrates are found, such as nematodes and molluscs—and the deuterostomes, containing the echinoderms and chordates.
Life forms interpreted. Many modern animal phyla became established in the fossil record as marine species during the Cambrian explosion which began around 542 million years ago. 6,331 groups of genes common to all living animals have been identified. Aristotle divided animals into those with those without. Carl Linnaeus created the first hierarchical biological classification for animals in 1758 with his Systema Naturae, which Jean-Baptiste Lamarck expanded into 14 phyla by 1809. In 1874, Ernst Haeckel divided the animal kingdom into the multicellular Metazoa and the Protozoa, single-celled organisms no longer considered animals. In modern times, the biological classification of animals relies on advanced techniques, such as molecular phylogenetics, which are effective at demonstrating the evolutionary relationships between animal taxa. Humans make use of many other animal species for food, including meat and eggs. Dogs have been used in hunting, while many aquatic animals are hunted for sport.
Non-human animals have appeared in art from the earliest times and are featured in mythology and religion. The word "animal" comes from the Latin animalis, having soul or living being; the biological definition includes all members of the kingdom Animalia. In colloquial usage, as a consequence of anthropocentrism, the term animal is sometimes used nonscientifically to refer only to non-human animals. Animals have several characteristics. Animals are eukaryotic and multicellular, unlike bacteria, which are prokaryotic, unlike protists, which are eukaryotic but unicellular. Unlike plants and algae, which produce their own nutrients animals are heterotrophic, feeding on organic material and digesting it internally. With few exceptions, animals breathe oxygen and respire aerobically. All animals are motile during at least part of their life cycle, but some animals, such as sponges, corals and barnacles become sessile; the blastula is a stage in embryonic development, unique to most animals, allowing cells to be differentiated into specialised tissues and organs.
All animals are composed of cells, surrounded by a characteristic extracellular matrix composed of collagen and elastic glycoproteins. During development, the animal extracellular matrix forms a flexible framework upon which cells can move about and be reorganised, making the formation of complex structures possible; this may be calcified, forming structures such as shells and spicules. In contrast, the cells of other multicellular organisms are held in place by cell walls, so develop by progressive growth. Animal cells uniquely possess the cell junctions called tight junctions, gap junctions, desmosomes. With few exceptions—in particular, the sponges and placozoans—animal bodies are differentiated into tissues; these include muscles, which enable locomotion, nerve tissues, which transmit signals and coordinate the body. There is an internal digestive chamber with either one opening or two openings. Nearly all animals make use of some form of sexual reproduction, they produce haploid gametes by meiosis.
These fuse to form zygotes, which develop via mitosis into a hollow sphere, called a blastula. In sponges, blastula larvae swim to a new location, attach to the seabed, develop into a new sponge. In most other groups, the blastula undergoes more complicated rearrangement, it first invaginates to form a gastrula with a digestive chamber and two separate germ layers, an external ectoderm and an internal endoderm. In most cases, a third germ layer, the mesoderm develops between them; these germ layers differentiate to form tissues and organs. Repeated instances of mating with a close relative during sexual reproduction leads to inbreeding depression within a population due to the increased prevalence of harmful recessive traits. Animals have evolved numerous mechanisms for avoiding close inbreeding. In some species, such as the splendid fairywren, females benefit by mating with multiple males, thus producing more offspring of higher genetic quality; some animals are capable of asexual reproduction, which results
Johann Jakob Heckel
Johann Jakob Heckel was an Austrian taxidermist and ichthyologist from Mannheim in the Electoral Palatinate. Though not a formally trained biologist, he worked his way up through the ranks to become the director of the Fish Collection at the Naturhistorisches Museum in Vienna. For the most part, he was not a traveler or explorer like many of the scientists of the time, he remained in Vienna, where he studied and catalogued specimens sent to him from the field. Among those who brought specimens to him were Karl Alexander Hügel, Joseph Russegger and Theodor Kotschy — involving collection activities in Kashmir, the Middle East and northeastern Africa that enriched the Vienna museum. Fish were his specialty and he worked with many of the greatest ichthyologists of his time including Cuvier, Bonaparte, Müller, Troschel. In the fields of systematics and taxonomy, he made significant contributions in his investigations of cyprinids, he wrote more than 60 works, the most notable of, "The freshwater fishes of the Austrian Danubian monarchy".
He worked on it for more than 24 years but died before its final publication, most from bacteria he was exposed to while getting a skeleton from a dead sperm whale. Cyprinen, Scaphirhynchus und andere ichthyologica, with Johann Natterer — Cyprinidae and other ichthyologica. Fische aus Caschmir, with Karl Alexander Hügel — Fish of Kashmir. Die Süßwasserfische der österreichischen Monarchie, mit Rücksicht auf die angränzenden Länder bearbeitet - The freshwater fishes of the Austrian monarchy, processed with regard to adjacent countries, with Rudolf Kner. Beiträge zur kenntniss der fossilen fische Österreichs, — Contribution to the knowledge of Austrian fossil fish. Neue Beiträge zur Kenntniss der fossilen Fische Österreichs, with Rudolf Kner — New contribution to the knowledge of Austrian fossil fish. Austrian Natural History Museum at Naturhistorisches Museum