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Broad Stingray
The Broad stingray (''Bathytoshia lata''), also known as the Brown stingray or Hawaiian stingray, is a species of stingray Stingrays are a group of sea rays, which are cartilaginous fish related to sharks. They are classified in the suborder Myliobatoidei of the order Myliobatiformes and consist of eight families: Hexatrygonidae (sixgill stingray), Plesiobatidae ( ... in the family (biology), family Dasyatidae. The predominant species of stingray in the inshore waters of the Hawaiian Islands, this benthic fish typically inhabits sandy or muddy flats at depths greater than . Usually growing to across, the broad stingray has a wide, diamond-shaped pectoral fin disc with a protruding snout tip and a long tail with a ventral fin fold. At night, this species actively forages for benthic, bottom-dwelling invertebrates and bony fishes, often near the boundaries of reefs. Reproduction is aplacental viviparous. As substantial threats to its population do not seem to exist, IUCN has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samuel Garman
Samuel Walton Garman (June 5, 1843 – September 30, 1927), or "Garmann" as he sometimes styled himself, was a naturalist/zoologist from Pennsylvania. He became noted as an ichthyologist and herpetologist. Biography Garman was born in Indiana County, Pennsylvania, on 5 June 1843. In 1868 he joined an expedition to the American West with John Wesley Powell. He graduated from the Illinois State Normal University in 1870, and for the following year was principal of the Mississippi State Normal School. In 1871, he became professor of natural sciences in Ferry Hall Seminary, Lake Forest, Illinois, and a year later became a special pupil of Louis Agassiz. He was a friend and regular correspondent of the naturalist Edward Drinker Cope, and in 1872 accompanied him on a fossil hunting trip to Wyoming. In 1870 he became assistant director of herpetology and ichthyology at Harvard's Museum of Comparative Zoology. His work was mostly in the classification of fish, especially sharks, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific Journal
In academic publishing, a scientific journal is a periodical publication intended to further the progress of science, usually by reporting new research. Content Articles in scientific journals are mostly written by active scientists such as students, researchers, and professors instead of professional journalists. There are thousands of scientific journals in publication, and many more have been published at various points in the past (see list of scientific journals). Most journals are highly specialized, although some of the oldest journals such as ''Nature'' publish articles and scientific papers across a wide range of scientific fields. Scientific journals contain articles that have been peer reviewed, in an attempt to ensure that articles meet the journal's standards of quality and scientific validity. Although scientific journals are superficially similar to professional magazines, they are actually quite different. Issues of a scientific journal are rarely read casuall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speciation
Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages. Charles Darwin was the first to describe the role of natural selection in speciation in his 1859 book ''On the Origin of Species''. He also identified sexual selection as a likely mechanism, but found it problematic. There are four geographic modes of speciation in nature, based on the extent to which speciating populations are isolated from one another: allopatric speciation, allopatric, peripatric speciation, peripatric, parapatric speciation, parapatric, and sympatric speciation, sympatric. Speciation may also be induced artificially, through animal husbandry, agriculture, or laboratory experiments of speciation, laboratory experiments. Whether genetic drift is a minor or major contributor to speciation is the subject of much ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe and Asia from the "New World" of the Americas in the European perception of the World. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and North and South America to the west. As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). The Atlantic Ocean is divided in two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean split at about 8°N. Scientific explorations of the Atlanti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longtail Stingray
The longtail stingray (''Dasyatis longa'', often misspelled ''longus''), is a species of stingray in the family Dasyatidae, found in the eastern Pacific Ocean from Baja California to Colombia. It inhabits sandy habitats down to a depth of . Measuring up to across, this species has a rhomboid pectoral fin disc, a lower (but not upper) fin fold on the tail, and numerous dermal denticles along the back and behind the stinging spine. The longtail stingray feeds mainly on bottom-dwelling bony fishes and crustaceans. It is aplacental viviparous, with females giving birth to 1–5 young in late summer. It is caught for food, likely throughout its range, but specific fishery data is lacking. Taxonomy and phylogeny American zoologist Samuel Garman published the original description of the longtail stingray in an 1880 issue of the scientific journal ''Bulletin of the Museum of Comparative Zoology''. He gave it the name ''Trygon longa'', in reference to the long tail, and designated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Stingray
The southern stingray (''Hypanus americanus'') is a whiptail stingray found in tropical and subtropical waters of the Western Atlantic Ocean from New Jersey to southern Brazil. It has a flat, diamond-shaped disc, with a mud brown, olive, and grey dorsal surface and white underbelly (ventral surface). The barb on its tail is serrated and covered in a venomous mucus, used for self-defense. Description The southern stingray is adapted for life on the sea bed. Its flattened, diamond-shaped body is more angular than other rays.Southern Stingray Southern stingray Biological Profile, Ichthyology Department, Florida Museum of Natural History (August, 2007) - via ARKive The top of the body varies between olive brown and green in adults, dark grey in juveniles, whilst the underside is white. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species (extinct or extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between organisms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roughtail Stingray
The roughtail stingray (''Bathytoshia centroura'') is a species of stingray in the family Dasyatidae, with separate populations in coastal waters of the northwestern, eastern, and southwestern Atlantic Ocean. This bottom-dwelling species typically inhabits sandy or muddy areas with patches of invertebrate cover, at a depth of . It is seasonally migratory, overwintering in offshore waters and moving into coastal habitats for summer. The largest whip-tail stingray in the Atlantic, the roughtail stingray grows up to across and in weight. It is plain in color, with an angular, diamond-shaped pectoral fin disc and a long, whip-like tail bearing a subtle fin fold underneath. The many thorns on its back and tail serve to distinguish it from other stingrays that share its range. Often found lying on the bottom buried in sediment, the roughtail stingray is a generalist predator that feeds on a variety of benthic invertebrates and bony fishes. It is aplacental viviparous, with the embr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sister Species
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and taxon B are sister groups to each other. Taxa A and B, together with any other extant or extinct descendants of their most recent common ancestor (MRCA), form a monophyletic group, the clade AB. Clade AB and taxon C are also sister groups. Taxa A, B, and C, together with all other descendants of their MRCA form the clade ABC. The whole clade ABC is itself a subtree of a larger tree which offers yet more sister group relationships, both among the leaves and among larger, more deeply rooted clades. The tree structure shown connects through its root to the rest of the universal tree of life. In cladistic standards, taxa A, B, and C may represent specimens, species, genera, or any other taxonomic units. If A and B are at the same taxonomic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology is a branch of biology dealing with the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance (shape, structure, colour, pattern, size), i.e. external morphology (or eidonomy), as well as the form and structure of the internal parts like bones and organs, i.e. internal morphology (or anatomy). This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Friedrich Burdach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups of organisms. These relationships are determined by Computational phylogenetics, phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, protein amino acid sequences, or morphology. The result of such an analysis is a phylogenetic tree—a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. The tips of a phylogenetic tree can be living taxa or fossils, and represent the "end" or the present time in an evolutionary lineage. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An unrooted tree diagram (a network) makes no assumption about the ancestral line, and does ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Hawaii
The history of Hawaii describes the era of human settlements in the Hawaiian Islands. The islands were first settled by Polynesians sometime between 124 and 1120 AD. Hawaiian civilization was isolated from the rest of the world for at least 500 years. An expedition led by British explorer James Cook is usually considered to be the first group of Europeans to arrive in the Hawaiian Islands, which they did in 1778. However, Spanish historians and some other researchers state that the Spanish captain Ruy López de Villalobos was the first European to see the islands in 1542. The Spanish named these islands "Isla de Mesa, de los Monjes y Desgraciada" (1542), being on the route linking the Philippines with Mexico across the Pacific Ocean, between the ports of Acapulco and Manila, which were both part of New Spain. Within five years after Cook's arrival, European military technology helped Kamehameha I, ruler of the island of Hawaii, conquer and unify the islands for the first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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