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Austin Blind Salamander
The Austin blind salamander (''Eurycea waterlooensis'') is an endangered species of salamander in the family Plethodontidae, endemic to Barton Springs in Austin, Texas, United States. Its name is derived from Waterloo, the original name of Austin. Austin blind salamanders, typically juveniles, have been observed at spring outlets. However, probably most of the population lives in subterranean cavities, and its total abundance is unknown, but it seems much less abundant than the sympatric Barton Springs salamander (''E. sosorum''). It is a totally aquatic species that is paedomorphic Neoteny (), also called juvenilization,Montagu, A. (1989). Growing Young. Bergin & Garvey: CT. is the delaying or slowing of the physiological, or somatic, development of an organism, typically an animal. Neoteny is found in modern humans compared ... (does not metamorphose). References Cave salamanders Eurycea Amphibians of the United States Endemic fauna of Texas Taxonomy articles create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Hillis
David Mark Hillis (born December 21, 1958 in Copenhagen, Denmark) is an American evolutionary biologist, and the Alfred W. Roark Centennial Professor of Biology at the University of Texas at Austin. He is best known for his studies of molecular evolution, phylogeny, and vertebrate systematics. He created the popular Hillis Plot depiction of the evolutionary tree of life. Early life David Hillis was born in Copenhagen, Denmark in 1958, the son of William Hillis, an epidemiologist, and Aryge Briggs Hillis, a biostatistician. Hillis lived his early years in Denmark, Belgian Congo, India, and the United States, where he developed his interests in biology and biodiversity. He has two sons, Erec and Jonathan. His younger son, Jonathan Hillis, served in 2011 as the National Chief of the Order of the Arrow, the Honor Society of the Boy Scouts of America. His brother is computer scientist W. Daniel Hillis, and his sister is Argye E. Hillis, a professor of neurology at Johns Hopkin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plethodontidae
Plethodontidae, or lungless salamanders, are a family of salamanders. Most species are native to the Western Hemisphere, from British Columbia to Brazil, although a few species are found in Sardinia, Europe south of the Alps, and South Korea. In terms of number of species, they are by far the largest group of salamanders. 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 duration of embryonic development. Additionally, the evolutionary loss of the aquatic larval stage is related to a diminishing dep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barton Springs
Barton Springs is a set of four natural water springs located at Barton Creek on the grounds of Zilker Park in Austin, Texas, resulting from water flowing through the Edwards Aquifer. The largest spring, Main Barton Spring (also known as Parthenia, "the mother spring") supplies water to Barton Springs Pool, a popular recreational destination in Austin. The smaller springs are located nearby, two with man-made structures built to contain and direct their flow. The springs are the only known habitat of the Barton Springs Salamander, an endangered species. The Barton Creek National Archeological and Historic District was formed in 1985. Geology Barton Springs is the main discharge point for the Barton Springs segment of the Edwards Aquifer of Texas, a well known karst aquifer. Geologically, the aquifer is composed of limestone from the Cretaceous period, about 100 million years old. Fractures, fissures, conduits, and caves have developed in this limestone. Both physical forces, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Austin
Austin is the capital city of the U.S. state of Texas, as well as the seat and largest city of Travis County, with portions extending into Hays and Williamson counties. Incorporated on December 27, 1839, it is the 11th-most-populous city in the United States, the fourth-most-populous city in Texas, the second-most-populous state capital city, and the most populous state capital that is not also the most populous city in its state. It has been one of the fastest growing large cities in the United States since 2010. Downtown Austin and Downtown San Antonio are approximately apart, and both fall along the Interstate 35 corridor. Some observers believe that the two regions may some day form a new "metroplex" similar to Dallas and Fort Worth. Austin is the southernmost state capital in the contiguous United States and is considered a " Beta −" global city as categorized by the Globalization and World Cities Research Network. As of 2021, Austin had an estimated populati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by both List of U.S. states and territories by area, area (after Alaska) and List of U.S. states and territories by population, population (after California). Texas shares borders with the states of Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the west, and the Mexico, Mexican States of Mexico, states of Chihuahua (state), Chihuahua, Coahuila, Nuevo León, and Tamaulipas to the south and southwest; and has a coastline with the Gulf of Mexico to the southeast. Houston is the List of cities in Texas by population, most populous city in Texas and the List of United States cities by population, fourth-largest in the U.S., while San Antonio is the second most pop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barton Springs Salamander
The Barton Springs salamander (''Eurycea sosorum'') is an endangered lungless salamander. It is endemic to Texas, United States. It was first found in Barton Springs in Austin, but is now also known from other localities in the nearby Travis and Hays Counties. Barton Springs is located within Zilker Park which is situated in the Edwards Aquifer in Austin, Texas. Eliza Springs, located within Barton Springs, has one of the largest populations of Barton Springs salamanders. Habitat The Barton Springs salamander prefers clear water and are typically found near openings of springs. These salamanders can also be found under rocks or gravel, within aquatic vegetation, and algae. Barton Springs salamanders can live in water depths ranging from 0.1 to 5 meters. The springs in which these salamanders inhabit flow year-round and retain a constant temperature of around 20°C. Description Barton Springs salamanders are average-sized (adults grow to approximately in total length) an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paedomorphic
Neoteny (), also called juvenilization,Montagu, A. (1989). Growing Young. Bergin & Garvey: CT. is the delaying or slowing of the physiological, or somatic, development of an organism, typically an animal. Neoteny is found in modern humans compared to other primates. In progenesis or paedogenesis, sexual development is accelerated. Both neoteny and progenesis result in paedomorphism (as having the form typical of children) or paedomorphosis (changing towards forms typical of children), a type of heterochrony. It is the retention in adults of traits previously seen only in the young. Such retention is important in evolutionary biology, domestication and evolutionary developmental biology. Some authors define paedomorphism as the retention of larval traits, as seen in salamanders.Schell, S. C. ''Handbook of Trematodes of North America North of Mexico'', 1985, pg. 22 History and etymology The origins of the concept of neoteny have been traced to the Bible (as argued by Ashley Monta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cave Salamanders
A cave salamander is a type of salamander that primarily or exclusively inhabits caves, a group that includes several species. Some of these animals have developed special, even extreme, adaptations to their subterranean environments. Some species have only rudimentary (or even absent) eyes (''blind salamanders''). Others lack pigmentation, rendering them a pale yellowish or pinkish color (e.g., ''Eurycea rathbuni''). With the notable exception of ''Proteus anguinus'', all "cave salamanders" are members of the family Plethodontidae ("lungless salamanders"). History The first dedicated scientific study of a cave animal was focused upon a cave salamander, ''Proteus anguinus''. It was originally identified as a "dragon's larva" by Johann Weikhard von Valvasor in 1689. Later, the Austrian naturalist Joseph Nicolaus Lorenz described it scientifically in 1768. Another early scientific description of a cave salamander was undertaken by Constantine Samuel Rafinesque in 1822 while he w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphibians Of The United States
Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arboreal or freshwater aquatic ecosystems. Thus amphibians typically start out as larvae living in water, but some species have developed behavioural adaptations to bypass this. The young generally undergo metamorphosis from larva with gills to an adult air-breathing form with lungs. Amphibians use their skin as a secondary respiratory surface and some small terrestrial salamanders and frogs lack lungs and rely entirely on their skin. They are superficially similar to reptiles like lizards but, along with mammals and birds, reptiles are amniotes and do not require water bodies in which to breed. With their complex reproductive needs and permeable skins, amphibians are often ecological indicators; in recent decades there has been a dramatic decline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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