David A. Steen
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David A. Steen
David A. Steen is an American herpetologist and conservation biologist. He is Reptile and Amphibian Research Leader of the Fish and Wildlife Research Institute (Florida Fish and Wildlife Conservation Commission), and was previously a research professor at Auburn University, where he completed his Ph.D. Steen runs a popular Twitter account where he offers reptile and amphibian identification and dispels myths about oft-maligned snakes such as copperheads, cottonmouths, and rattlesnakes. He won the Mindlin Foundation's "Mindlin Science Communication Prize" in 2017 for his efforts in online science communication. He is author of the book Secrets of Snakes: the Science Beyond the Myths. In 2018, along with researchers Sean P. Graham, Richard Kline, and Crystal Kelehear, he described a new species of aquatic salamander endemic to the Gulf coastal plain, ''Siren reticulata The reticulated siren (''Siren reticulata''), also known commonly as the leopard eel, is a species of aquatic ...
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Herpetology
Herpetology (from Greek ἑρπετόν ''herpetón'', meaning "reptile" or "creeping animal") is the branch of zoology concerned with the study of amphibians (including frogs, toads, salamanders, newts, and caecilians (gymnophiona)) and reptiles (including snakes, lizards, amphisbaenids, turtles, terrapins, tortoises, crocodilians, and the tuataras). Birds, which are cladistically included within Reptilia, are traditionally excluded here; the scientific study of birds is the subject of ornithology. Thus, the definition of herpetology can be more precisely stated as the study of ectothermic (cold-blooded) tetrapods. Under this definition "herps" (or sometimes "herptiles" or "herpetofauna") exclude fish, but it is not uncommon for herpetological and ichthyological scientific societies to collaborate. Examples include publishing joint journals and holding conferences in order to foster the exchange of ideas between the fields, as the American Society of Ichthyologists and He ...
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Agkistrodon Contortrix
The eastern copperhead (''Agkistrodon contortrix''), also known as the copperhead, is a species of venomous snake, a pit viper, endemic to eastern North America; it is a member of the subfamily Crotalinae in the family Viperidae. The eastern copperhead has distinctive, dark brown, hourglass-shaped markings, overlaid on a light reddish brown or brown/gray background. The body type is heavy, rather than slender. Neonates are born with green or yellow tail tips, which progress to a darker brown or black within one year. Adults grow to a typical length (including tail) of . In most of North America, it favors deciduous forest and mixed woodlands. It may occupy rock outcroppings and ledges, but is also found in low-lying, swampy regions. During the winter, it hibernates in dens or limestone crevices, often together with timber rattlesnakes and black rat snakes. The eastern copperhead is known to feed on a wide variety of prey, including invertebrates (primarily arthropods) and ver ...
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American Ecologists
American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, people who self-identify their ancestry as "American" ** American English, the set of varieties of the English language native to the United States ** Native Americans in the United States, indigenous peoples of the United States * American, something of, from, or related to the Americas, also known as "America" ** Indigenous peoples of the Americas * American (word), for analysis and history of the meanings in various contexts Organizations * American Airlines, U.S.-based airline headquartered in Fort Worth, Texas * American Athletic Conference, an American college athletic conference * American Recordings (record label), a record label previously known as Def American * American University, in Washington, D.C. Sports teams Soccer * B ...
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Siren Reticulata
The reticulated siren (''Siren reticulata''), also known commonly as the leopard eel, is a species of aquatic salamander in the family Sirenidae. The species, which is endemic to the southeastern United States, was first formally described in 2018. This cryptic salamander is known only from three localities in southern Alabama and the Florida panhandle and is one of the largest animals in the United States to be newly described in the past 100 years. Description The reticulated siren is one of the largest species of extant (living) salamanders worldwide, reaching up to in total length, which rivals the hellbender of the Appalachian Mountains as both the largest amphibian in North America and the fourth largest salamander in the world. It has a greenish grey, eel-like body, large external gills, and two small front legs. The sides and belly are a lighter yellowish green. It has an average snout to vent length (SVL) of . ''S. reticulata'' differs from other ''Siren'' specie ...
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Gulf Coastal Plain
The Gulf Coastal Plain extends around the Gulf of Mexico in the Southern United States and eastern Mexico. This coastal plain reaches from the Florida Panhandle, southwest Georgia, the southern two-thirds of Alabama, over most of Mississippi, western Tennessee and Kentucky, into southern Illinois, the Missouri Bootheel, eastern and southern Arkansas, all of Louisiana, the southeast corner of Oklahoma, and easternmost Texas in the United States. It continues along the Gulf in northeastern and eastern Mexico, through Tamaulipas and Veracruz to Tabasco and the Yucatán Peninsula on the Bay of Campeche. Geography The Gulf Coastal Plain's southern boundary is the Gulf of Mexico in the U.S. and the Sierra Madre de Chiapas in Mexico. On the north, it extends to the Ouachita Highlands of the Interior Low Plateaus and the southern Appalachian Mountains. Its northernmost extent is along the Mississippi embayment (Mississippi Alluvial Valley) as far north as the southern tip of Illinois ...
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Endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to ...
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Salamander
Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All ten extant salamander families are grouped together under the order Urodela. Salamander diversity is highest in eastern North America, especially in the Appalachian Mountains; most species are found in the Holarctic realm, with some species present in the Neotropical realm. Salamanders rarely have more than four toes on their front legs and five on their rear legs, but some species have fewer digits and others lack hind limbs. Their permeable skin usually makes them reliant on habitats in or near water or other cool, damp places. Some salamander species are fully aquatic throughout their lives, some take to the water intermittently, and others are entirely terrestrial as adults. This group of amphibians is capable of regenerating lost lim ...
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Rattlesnake
Rattlesnakes are venomous snakes that form the genera ''Crotalus'' and ''Sistrurus'' of the subfamily Crotalinae (the pit vipers). All rattlesnakes are vipers. Rattlesnakes are predators that live in a wide array of habitats, hunting small animals such as birds and rodents. Rattlesnakes receive their name from the rattle located at the end of their tails, which makes a loud rattling noise when vibrated that deters predators or serves as a warning to passers-by. Rattlesnakes are the leading contributor to snakebite injuries in North America, but rarely bite unless provoked or threatened; if treated promptly, the bites are seldom fatal. The 36 known species of rattlesnakes have between 65 and 70 subspecies, all native to the Americas, ranging from British Columbia through Ontario in southern Canada, to central Argentina. The largest rattlesnake, the eastern diamondback, can measure up to in length. Rattlesnakes are preyed upon by hawks, weasels, king snakes, and a variety ...
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Cottonmouth
''Agkistrodon piscivorus'' is a species of pit viper in the subfamily Crotalinae of the family Viperidae. It is one of the world's few semiaquatic vipers (along with the Florida cottonmouth), and is native to the southeastern United States. As an adult, it is large and capable of delivering a painful and potentially fatal bite. When threatened, it may respond by coiling its body and displaying its fangs. Individuals may bite when feeling threatened or being handled in any way. It tends to be found in or near water, particularly in slow-moving and shallow lakes, streams, and marshes. It is a capable swimmer and, like several species of snakes, is known to occasionally enter bays and estuaries and swim between barrier islands and the mainland. Gloyd HK, Conant R (1990). ''Snakes of the ''Agkistrodon'' Complex: A Monographic Review''. Society for the Study of Amphibians and Reptiles. 614 pp. 52 plates. LCCN 89-50342. . The generic name is derived from the Greek words ''ankistron' ...
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Twitter
Twitter is an online social media and social networking service owned and operated by American company Twitter, Inc., on which users post and interact with 280-character-long messages known as "tweets". Registered users can post, like, and 'Reblogging, retweet' tweets, while unregistered users only have the ability to read public tweets. Users interact with Twitter through browser or mobile Frontend and backend, frontend software, or programmatically via its APIs. Twitter was created by Jack Dorsey, Noah Glass, Biz Stone, and Evan Williams (Internet entrepreneur), Evan Williams in March 2006 and launched in July of that year. Twitter, Inc. is based in San Francisco, California and has more than 25 offices around the world. , more than 100 million users posted 340 million tweets a day, and the service handled an average of 1.6 billion Web search query, search queries per day. In 2013, it was one of the ten List of most popular websites, most-visited websites and has been de ...
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Ecology
Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overlaps with the closely related sciences of biogeography, evolutionary biology, genetics, ethology, and natural history. Ecology is a branch of biology, and it is not synonymous with environmentalism. Among other things, ecology is the study of: * The abundance, biomass, and distribution of organisms in the context of the environment * Life processes, antifragility, interactions, and adaptations * The movement of materials and energy through living communities * The successional development of ecosystems * Cooperation, competition, and predation within and between species * Patterns of biodiversity and its effect on ecosystem processes Ecology has practical applications in conservation biology, wetland management, natural resource managemen ...
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Conservation Biology
Conservation biology is the study of the conservation of nature and of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction and the erosion of biotic interactions. It is an interdisciplinary subject drawing on natural and social sciences, and the practice of natural resource management. The conservation ethic is based on the findings of conservation biology. Origins The term conservation biology and its conception as a new field originated with the convening of "The First International Conference on Research in Conservation Biology" held at the University of California, San Diego in La Jolla, California, in 1978 led by American biologists Bruce A. Wilcox and Michael E. Soulé with a group of leading university and zoo researchers and conservationists including Kurt Benirschke, Sir Otto Frankel, Thomas Lovejoy, and Jared Diamond. The meeting was prompted due to concern over tropical deforestation, disappearin ...
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