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Ensatina Eschscholtzii
The ensatina (''Ensatina eschscholtzii'') is a species complex of plethodontid (lungless) salamanders found in coniferous forests, oak woodland and chaparralMonterey Ensatina San Diego Field Station, Viewed: April 24, 2005, Last updated: March 05, 2003 from , through Washington, |
John Edward Gray
John Edward Gray (12 February 1800 – 7 March 1875) was a British zoologist. He was the elder brother of zoologist George Robert Gray and son of the pharmacologist and botanist Samuel Frederick Gray (1766–1828). The same is used for a zoological name. Gray was keeper of zoology at the British Museum in London from 1840 until Christmas 1874, before the natural history holdings were split off to the Natural History Museum. He published several catalogues of the museum collections that included comprehensive discussions of animal groups and descriptions of new species. He improved the zoological collections to make them amongst the best in the world. Biography Gray was born in Walsall, but his family soon moved to London, where Gray studied medicine. He assisted his father in writing ''The Natural Arrangement of British Plants'' (1821). After being blackballed by the Linnean Society of London, Gray shifted his interest from botany to zoology. He began his zoological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California Coast Ranges
The Coast Ranges of California span from Del Norte County, California, Del Norte or Humboldt County, California, south to Santa Barbara County, California, Santa Barbara County. The other three coastal California mountain ranges are the Transverse Ranges, Peninsular Ranges and the Klamath Mountains. Physiographically, they are a section of the larger Pacific Border province, which in turn is part of the larger Geography of the United States Pacific Mountain System, Pacific Mountain System physiographic division. UNESCO has included the "California Coast Ranges Biosphere Reserve" in its Man and the Biosphere Programme of World Network of Biosphere Reserves since 1983. * Physiography The northern end of the California Coast Ranges overlap the southern end of the Klamath Mountains for approximately on the west. They extend southward for more than to where the coastline turns eastward along the Santa Barbara Channel, around the area of Point Conception. Here the southern end m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plethodontidae
Plethodontidae, or lungless salamanders, are a family of salamanders. With over 500 species, lungless salamanders are by far the largest family of salamanders in terms of their diversity. Most species are native to the Western Hemisphere, from British Columbia to Brazil. Only two extant genera occur in the Eastern Hemisphere: '' Speleomantes'' (native to Sardinia and mainland Europe south of the Alps) and '' Karsenia'' (native to South Korea). Biology Adult lungless salamanders have four limbs, with four toes on the fore limbs, and usually with five on the hind limbs. Within many species, mating and reproduction occur solely on land. Accordingly, many species also lack an aquatic larval stage, a phenomenon known as direct development in which the offspring hatch as fully-formed, miniature adults. Direct development is correlated with changes in the developmental characteristics of plethodontids compared to other families of salamanders including increases in egg size and durat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ensatina Eschscholtzii Platensis (3405603045)
The ensatina (''Ensatina eschscholtzii'') is a species complex of plethodontid (lungless) salamanders found in coniferous forests, oak woodland and chaparralMonterey Ensatina San Diego Field Station, Viewed: April 24, 2005, Last updated: March 05, 2003 from , through , |
Cutaneous Respiration
Cutaneous respiration, or cutaneous gas exchange (sometimes called skin breathing), is a form of respiration in which gas exchange occurs across the skin or outer integument of an organism rather than gills or lungs. Cutaneous respiration may be the sole method of gas exchange, or may accompany other forms, such as ventilation. Cutaneous respiration occurs in a wide variety of organisms, including insects, amphibians, fish, sea snakes, turtles, and to a lesser extent in mammals. Physical constraints Gas exchange in cutaneous respiration is controlled by three factors: *Ventilation: the rate of delivery of respiratory medium (water or air) to the respiratory surface *Diffusion: the passage of gases through the skin *Convection: the carrying of dissolved gases towards or away from the lungs Taxonomic diversity in chordates Fish Cutaneous respiration occurs in a variety of marine, intertidal, and freshwater fish. For aquatic respiration, fish respire primarily via gills but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoology
Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and how they interact with their ecosystems. Zoology is one of the primary branches of biology. The term is derived from Ancient Greek , ('animal'), and , ('knowledge', 'study'). Although humans have always been interested in the natural history of the animals they saw around them, and used this knowledge to domesticate certain species, the formal study of zoology can be said to have originated with Aristotle. He viewed animals as living organisms, studied their structure and development, and considered their adaptations to their surroundings and the function of their parts. Modern zoology has its origins during the Renaissance and early modern period, with Carl Linnaeus, Antonie van Leeuwenhoek, Robert Hooke, Charles Darwin, Gregor Mendel a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Highton
Richard Highton (December 24, 1927 – February 19, 2025) was an American herpetologist, an expert on the biological classification of woodland salamanders. Background Highton was born in Chicago. His father encouraged his son to have an interest in herpetology. In 1950 he was awarded a bachelor's degree in biology, mathematics and sociology from New York University, with his studies interrupted by military service. He received his master's degree and Doctorate in Philosophy from the University of Florida. In 1950 he married Anne Adams and they had four children together. Highton died on February 19, 2025, at the age of 97. Career A field visit to the southern Appalachians mountains in 1948 with Carl Gans was the start of his work on salamanders. In 1956 he joined the Zoology Department University of Maryland College Park, with emphasis on genetics and was Professor Emeritus in Biology. On his retirement in 1998, his collection of approximately 140,000 salamander specimens was ... [...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. Whether genetic drift is a minor or major contributor to speciation is the subject of much ongoing discussion. Rapid sympatric speciation can take place through polyploidy, such as by doubling of chromosome number; the result is progeny wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Ancestor's Tale
''The Ancestor's Tale: A Pilgrimage to the Dawn of Life'' is a 2004 science book by Richard Dawkins and Yan Wong that delves into the topic of evolution. The book adopts a unique approach, retracing the path of humans in reverse chronological order through evolutionary history. Along the way, it introduces readers to various species, referred to as humanity's cousins, as they converge on shared common ancestors. Drawing on scientific principles and research, "The Ancestor's Tale" offers an accessible and thought-provoking exploration of life's origins and the intricate relationships that connect all living beings. Synopsis The book follows a path backwards in time through evolution and meets different groupings of organisms. In this backward chronology, the ancestors of any set of species must eventually meet at a particular moment. The last common ancestor is the one that they all share which the authors call a "concestor". The oldest concestor, LUCA, short for Last Universal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a different organism is called a chimera. Hybrids are not always intermediates between their parents such as in blending inheritance (a now discredited theory in modern genetics by particulate inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridization, which include genetic and morph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horseshoe
A horseshoe is a product designed to protect a horse hoof from wear. Shoes are attached on the palmar surface (ground side) of the hooves, usually nailed through the insensitive hoof wall that is anatomically akin to the human toenail, although much larger and thicker. However, there are also cases where shoes are glued. Horseshoes are available in a wide variety of materials and styles, developed for different types of horses and for the work they do. The most common materials are steel and aluminium, but specialized shoes may include use of rubber, plastic, magnesium, titanium, or copper.Price, Steven D. (ed.) ''The Whole Horse Catalog: Revised and Updated'' New York:Fireside 1998 , pp. 84–87. Steel tends to be preferred in sports in which a strong, long-wearing shoe is needed, such as polo, eventing, show jumping, and western riding events. Aluminium shoes are lighter, making them common in horse racing where a lighter shoe is desired, and often facilitate certain ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Valley (California)
The Central Valley is a broad, elongated, flat valley that dominates the interior of California, United States. It is wide and runs approximately from north-northwest to south-southeast, inland from and parallel to the Pacific coast. It covers approximately , about 11% of California's land area. The valley is bounded by the California Coast Ranges, Coast Ranges to the west and the Sierra Nevada to the east. The Central Valley is a region known for its agricultural productivity. It provides a large share of the food produced in California, which provides more than half of the fruits, vegetables, and nuts grown in the United States. More than of the valley are irrigated via reservoirs and canals. The valley hosts many cities, including the state capital Sacramento, California, Sacramento, as well as Redding, California, Redding, Chico, California, Chico, Yuba City, California, Yuba City, Woodland, California, Woodland, Davis, California, Davis, Stockton, California, Stockton, M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
