Gourt > Science > Biology > Flora and Fauna > Animalia > Chordata > Amphibia (24)
Amphibians (class Amphibia) are a taxon of animals that include all tetrapods, four-legged vertebrates, that do not have amniotic eggs.(from Greek αμφις "both" and βιος "life") are ectotherms, and generally spend part of their time on land, but most do not have the adaptations to an entirely terrestrial existence found in most other modern tetrapods (amniotes). There are around 6,000 described, living species of amphibians. The study of amphibians and reptiles is known as herpetology.
History of amphibians
Amphibians developed with the characteristics of pharyngeal slits/gills, a dorsal nerve cord, a notochord, and a post-anal tail at different stages of their life. Though early tetrapods (which appeared 390 million years ago in the Devonian period) are often referred to as "amphibians", the first true amphibians (of the order Temnospondyli) appeared during the early Carboniferous period. During the late Carboniferous, Permian and Triassic periods, amphibians were extremely diverse, including many large and small forms, some newt and salamander-like, others resembling snakes or eels, and some large-snouted forms that were very like small (about 1.5 meter long) crocodiles (e.g. Archegosaurus). The drying out of the coal swamps during the latest Carboniferous and again at the end of the Early Permian diminished many of the environments of these Paleozoic amphibians, with the result that many types died out, and they were supplanted by reptiles. However both large and small amphibians still continued to flourish in rivers and lakes of the Late Permian, alongside the diverse therapsids or mammal-like reptiles that were the dominant land animals of that time. During the following, Triassic period, there were many genera with large, sometimes very flattened heads and very weak limbs; some of these, like Paracyclotosaurus, Cyclotosaurus and Mastodonsaurus were several meters in length. Apart from a few stragglers, all these large amphibians died out at the Triassic-Jurassic extinction event, and the majority of Jurassic amphibians belonged to modern groups, and would look familiar today.
Throughout their history, amphibians have ranged in size from large forms, such as the above mentioned Triassic genera, the 5 foot (150cm) long Eryops of the Permian period, and the Giant Japanese and Chinese Salamanders of today, down to the tiny Brachycephalus didactylus (Brazilian Gold Frog) and Eleutherodactylus iberia (leptodactylid frog) from Cuba, with a total length of 9.6-9.8 millimeters (0.4 inches). Amphibians have mastered almost every climate on earth from the hottest deserts to the frozen arctic.
More on [ Amphibian ]
Amphibians :: Reptiles and Amphibians
Amphibia :: Animal
Herpetology :: Chordates
RT: @mancini: La audiencia es tu jefe http://www.amphibia.com.ar/la-audiencia-es-tu-jefe/
mareacultural (augusto rubio acosta) Mon, 07 Dec 2009 01:07:21 -0000
RT: @mancini: La audiencia es tu jefe http://www.amphibia.com.ar/la-audiencia-es-tu-jefe/
RT @mancini: La audiencia es tu jefe http://www.amphibia.com.ar/la-audiencia-es-tu-jefe/
froncal1 (Fiorella Roncal) Sun, 06 Dec 2009 20:46:13 -0000
RT @mancini: La audiencia es tu jefe http://www.amphibia.com.ar/la-audiencia-es-tu-jefe/
El jefe mas exigente sin duda RT @mancini: La audiencia es tu jefe http://www.amphibia.com.ar/la-audiencia-es-tu-jefe/
diegol19 (Diego Peralta Murias) Sun, 06 Dec 2009 20:43:16 -0000
El jefe mas exigente sin duda RT @mancini: La audiencia es tu jefe http://www.amphibia.com.ar/la-audiencia-es-tu-jefe/
La audiencia es tu jefe http://www.amphibia.com.ar/la-audiencia-es-tu-jefe/
mancini (Pablo Mancini) Sun, 06 Dec 2009 19:30:49 -0000
La audiencia es tu jefe http://www.amphibia.com.ar/la-audiencia-es-tu-jefe/
La audiencia es tu jefe http://www.amphibia.com.ar/4690
mancini (Pablo Mancini) Sun, 06 Dec 2009 19:28:24 -0000
La audiencia es tu jefe http://www.amphibia.com.ar/4690
⪠Listening ãªã ⪠Call The Night / Terra Amphibia 1 by Mani Neumeier + Guests http://twitpic.com/sewhf #iTwines
Sukeru_Penta (ã¾ã£ããing Sukeru) Sun, 06 Dec 2009 16:46:21 -0000
♪ Listening なう ♪ Call The Night / Terra Amphibia 1 by Mani Neumeier + Guests http://twitpic.com/sewhf #iTwines
Amphibian Checklist and Identification Guide - Taxonomic checklist for North America north of Mexico and detailed accounts, including photos and range maps, for dozens of species.
Meta Description: [ An online guide for the identification of amphibians in North America north of Mexico ]
Amphibian Declines in Australia - Research into the nature and causes including bibliography of published and unpublished material.
Meta Description: [ Links to bibliography of frog declines in Australia, current research and information on missing frogs ]
Amphibian Species of the World - Comprehensive searchable catalog of the recognized amphibian species of the world with synonymies and references to the taxonomic literature.
Amphibians of Hiroshima - Information and photos of the 6 species of salamanders and 13 frogs in Hiroshima, Japan.
500
AmphibiaWeb - Source for amphibian data and conservation resources.
ARMI National Atlas for Amphibian Distributions - A compilation of current and historic records of amphibian occurrences in the United States, with range maps for each species to the county level. From the Amphibian Research and Monitoring Initiative.
Connecticut Amphibians - Photos and life histories of the state's frogs and salmanders; recordings of frog calls.
Discover Canada's Amphibians - Explores amphibian morphology, ecology and evolution. All Canadian species are described in-depth.
Meta Description: [ This site explores amphibian morphology, ecology and evolution.
All Canadian species are described in-depth! ]
Froghoo! from Amphibian Conservation Alliance - The internet's only search engine for amphibian conservation, biology, management, education, policy, breeding, and care information, with links to more than 1000 web sites, news articles, background papers, and books.
Frogs.org - Amphibian Conservation Alliance site with information and resources related to amphibians and amphibian conservation in the USA.
Meta Description: [ FROGS.ORG is a “one dot stop” for finding and publishing amphibian conservation resources online. Get info. Take Action. Donate. ]
Living Amphibians - Introduction to the taxonomy of Amphibia, including Salientia (frogs and toads), Caudata (salamanders and newts), and gymnophiona (caecilians).
Livingunderworld - Amphibian information resource, with species databases, captive care guides, articles, links, and photos.
Meta Description: [ An educational web project dedicated to the conservation, and preservation of amphibians. ]
North American Reporting Center for Amphibian Malformations - Data and information on the issue of malformed amphibians, with an emphasis on North American occurrences.
Meta Description: [ Data and information on the issue of malformed amphibians, with an
emphasis on North American occurrences. ]
Order Anura - Brief description of the order and its families, with representative photos for each family.
| Cirque De La Mer Soundtrack | |
| Next Video | |
