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Thirteen-lined Ground Squirrel
The thirteen-lined ground squirrel (''Ictidomys tridecemlineatus''), also known as the striped gopher, leopard ground squirrel, squinney, (formerly known as the leopard-spermophile in the age of Audubon), is a ground squirrel that is widely distributed over grasslands and prairies of North America. Description It is brownish, with 13 alternating brown and whitish longitudinal lines (sometimes partially broken into spots) on its back and sides, creating rows of whitish spots within dark lines. Taxonomy This species has usually been placed in the genus ''Spermophilus'' with about 40 other species. As this large genus is paraphyletic to prairie dogs, marmots, and antelope squirrels, Kristofer Helgen and colleagues have split it into eight genera, placing the thirteen-lined ground squirrel in ''Ictidomys'' with two other species. Behavior The thirteen-lined ground squirrel is strictly diurnal and is especially active on warm days. A solitary or only somewhat colonial hiber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samuel Latham Mitchill
Samuel Latham Mitchill (August 20, 1764September 7, 1831) was an American physician, naturalist, and politician who lived in Plandome, New York. Early life Samuel Mitchill was born in Hempstead in the Province of New York, the son of Robert Mitchill and his wife, Mary Latham, both Quakers. He was sent to Scotland and graduated in 1786 from the University of Edinburgh Medical School with an M.D., his education being paid for by a wealthy uncle. Returning to the United States after medical school, Mitchill also completed law school. As a lawyer, he oversaw the purchase of lands in western New York from the Iroquois Indians in 1788. Career Mitchill taught chemistry, botany, and natural history at Columbia College from 1792 to 1801 and was a founding editor of ''The Medical Repository'', the first medical journal in the United States. In 1793, he was elected a Foreign Fellow of the Royal Society of Edinburgh. His proposers were James Gregory, Dugald Stewart, and John Rotherham. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cicada
The cicadas () are a superfamily, the Cicadoidea, of insects in the order Hemiptera (true bugs). They are in the suborder Auchenorrhyncha, along with smaller jumping bugs such as leafhoppers and froghoppers. The superfamily is divided into two families, the Tettigarctidae, with two species in Australia, and the Cicadidae, with more than 3,000 species described from around the world; many species remain undescribed. Cicadas have prominent eyes set wide apart, short antennae, and membranous front wings. They have an exceptionally loud song, produced in most species by the rapid buckling and unbuckling of drumlike tymbals. The earliest known fossil Cicadomorpha appeared in the Upper Permian period; extant species occur all around the world in temperate to tropical climates. They typically live in trees, feeding on watery sap from xylem tissue, and laying their eggs in a slit in the bark. Most cicadas are cryptic. The vast majority of species are active during the day as adults, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of The Great Lakes Region (North America)
Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is ''funga''. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Greek equivalent of fauna. ''Fauna'' is also the word for a book that catalogues the animals in such a manner. The term was first used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of The Plains-Midwest (United States)
Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is ''funga''. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Greek equivalent of fauna. ''Fauna'' is also the word for a book that catalogues the animals in such a manner. The term was first used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammals Of The United States
About 490 species of mammals are recorded in the United States. Unincorporated territories like for example Puerto Rico, Guam or Northern Mariana Islands are not covered. Mammals introduced and extinct in the Holocene except Pleistocene/Holocene boundary are included. According to the IUCN Red List 3 of these species are critically endangered, 20 endangered, 15 vulnerable, 20 near threatened and 4 extinct. Some species are identified as indicated below: *(A) - Accidental *(E) - Extinct *(Ex) - Extirpated (extinct in the US, but exists elsewhere in the world) *(I) - Introduced The following tags are used to highlight each species' conservation status as assessed by the International Union for Conservation of Nature: (v. 2013.2, the data are current as of March 5, 2014) and the Endangered Species Act: (the data are current as of March 28, 2014) Subclass: Theria Infraclass: Metatheria Order: Didelphimorphia (common opossums) ---- Didelphimorphia is the order of common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ensembl
Ensembl genome database project is a scientific project at the European Bioinformatics Institute, which provides a centralized resource for geneticists, molecular biologists and other researchers studying the genomes of our own species and other vertebrates and model organisms. Ensembl is one of several well known genome browsers for the retrieval of genomic information. Similar databases and browsers are found at NCBI and the University of California, Santa Cruz (UCSC). History The human genome consists of three billion base pairs, which code for approximately 20,000–25,000 genes. However the genome alone is of little use, unless the locations and relationships of individual genes can be identified. One option is manual annotation, whereby a team of scientists tries to locate genes using experimental data from scientific journals and public databases. However this is a slow, painstaking task. The alternative, known as automated annotation, is to use the power of computers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chipmunk
Chipmunks are small, striped rodents of the family Sciuridae. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia. Taxonomy and systematics Chipmunks may be classified either as a single genus, ''Tamias'', or as three genera: ''Tamias'', of which the eastern chipmunk (''T. striatus'') is the only living member; ''Eutamias'', of which the Siberian chipmunk (''E. sibiricus'') is the only living member; and ''Neotamias'', which includes the 23 remaining, mostly western North American, species. These classifications were treated as subgenera due to the chipmunks' morphological similarities. As a result, most taxonomies over the twentieth century have placed the chipmunks into a single genus. However, studies of mitochondrial DNA show that the divergence between each of the three chipmunk groups is comparable to the genetic differences between ''Marmota'' and ''Spermophilus'', so the three genera classifications have b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golden-mantled Ground Squirrel
The golden-mantled ground squirrel (''Callospermophilus lateralis'') is a ground squirrel native to western North America. It is distributed in the Rocky Mountains of British Columbia and Alberta, and through much of the western United States. Description This ground squirrel is generally about in length. The weight range for adults is between 120 and 394 grams (0.26 to 0.86 lbs.) It has whitish or yellow-gray underparts. The tail is brown to black with buff edges and a yellowish to reddish underside. It has pale rings around the eyes. The "mantle" across the shoulders is tawny to reddish, with males having a deeper reddish tinge. This species is distinguished from similar ground squirrels by a black-bordered white stripe down each side of the back and is distinguished from similar looking chipmunks by its lack of facial stripes.Bartels, M. A. and D. P. Thompson''Spermophilus lateralis''. ''In'': Wilson, D. E. & D. M. Reeder (Eds). 2005. ''Mammal Species of the World. A Taxonomi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycogen
Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in animals, fungi, and bacteria. The polysaccharide structure represents the main storage form of glucose in the body. Glycogen functions as one of two forms of energy reserves, glycogen being for short-term and the other form being triglyceride stores in adipose tissue (i.e., body fat) for long-term storage. In humans, glycogen is made and stored primarily in the cells of the liver and skeletal muscle. In the liver, glycogen can make up 5–6% of the organ's fresh weight, and the liver of an adult, weighing 1.5 kg, can store roughly 100–120 grams of glycogen. In skeletal muscle, glycogen is found in a low concentration (1–2% of the muscle mass) and the skeletal muscle of an adult weighing 70 kg stores roughly 400 grams of glycogen. The amount of glycogen stored in the body—particularly within the muscles and liver—mostly depends on physical training, bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidative Damage
Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal redox state of cells can cause toxic effects through the production of peroxides and free radicals that damage all components of the cell, including proteins, lipids, and DNA. Oxidative stress from oxidative metabolism causes base damage, as well as strand breaks in DNA. Base damage is mostly indirect and caused by the reactive oxygen species generated, e.g., O2− (superoxide radical), OH (hydroxyl radical) and H2O2 (hydrogen peroxide). Further, some reactive oxidative species act as cellular messengers in redox signaling. Thus, oxidative stress can cause disruptions in normal mechanisms of cellular signaling. In humans, oxidative stress is thought to be involved in the development of attention deficit hyperactivity disorder, cancer, Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antioxidant
Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubricants, to prevent oxidation, and to foods to prevent spoilage, in particular the rancidification of oils and fats. In cells, antioxidants such as glutathione, mycothiol or bacillithiol, and enzyme systems like superoxide dismutase, can prevent damage from oxidative stress. The only dietary antioxidants are vitamins A, C, and E, but the term ''antioxidant'' has also been applied to numerous other dietary compounds that only have antioxidant properties in vitro, with little evidence for antioxidant properties in vivo. Dietary supplements marketed as antioxidants have not been shown to maintain health or prevent disease in humans. History As part of their adaptation from marine life, terrestrial plants began producing non-marine antioxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skeletal Muscle
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle tissue, and are often known as muscle fibers. The muscle tissue of a skeletal muscle is striated – having a striped appearance due to the arrangement of the sarcomeres. Skeletal muscles are voluntary muscles under the control of the somatic nervous system. The other types of muscle are cardiac muscle which is also striated and smooth muscle which is non-striated; both of these types of muscle tissue are classified as involuntary, or, under the control of the autonomic nervous system. A skeletal muscle contains multiple muscle fascicle, fascicles – bundles of muscle fibers. Each individual fiber, and each muscle is surrounded by a type of connective tissue layer of fascia. Muscle fibers are formed from the cell fusion, fusion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
