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| | Amniote - Wikipedia, the free encyclopedia |
 | | The first amniotes looked like small lizards, and their eggs were small and covered with a membrane, not a hard shell like often seen today. | | | But real growth was not possible until they stopped relying on small invertebrates as their main food source, and started to eat plants or other vertebrates, or returned to the water. | | | Some modern amphibians lay eggs on land but without any protection to speak of, while others like some lungless salamanders and Amphiuma also lay small eggs on land, but these are covered by a rubber-like membrane even if they lack advanced traits like an amnion. |
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http://en.wikipedia.org/wiki/Amniote
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| | Amniota |
| | Development of extraembryonic membranes in an amniote egg (chick). | | | As in other vertebrates, nutrients for the developing embryo are stored in the yolk sac, which is much larger in amniotes than in vertebrates generally. | | | The amniotic egg, together with a penis for internal fertilization, loss of a free-living larval stage in the life cycle, and the ability to bury their eggs, enabled amniotes to escape the bonds that confined their ancestors' reproductive activities to aquatic environments. |
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http://tolweb.org/tree?group=Amniota&contgroup=Terrestrial_Vertebrates
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| | Zimmer Chapter Four |
| | The Romerian concept was that amniotes evolved eggs that could survive drought. | | | Fully terrestrial egg laying probably preceded the amniote egg by a long time span -- possibly before the evolution of tetrapod limbs. | | | Permits growth to a larger size, resists desiccation and permits air-breathing young to merge. |
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http://www.ucalgary.ca/~zoology/Zool571/ch4.htm
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| | Phylogeny and Classification of Amniotes |
| | The pineal foramen of most other amniotes is located close to the mid-length of the interparietal suture, or slightly anterior to this (Fig. | | | The transverse flange of other amniotes extends transversely or posterolaterally from the area of the basicranial articulation (Fig. | | | The paroccipital process of most other amniotes is a broad, thin, vertical flange. |
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http://tolweb.org/accessory/Phylogeny_and_Classification_of_Amniotes?acc_id=462
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| | Evolution of the Amniote Brain |
| | These were the earliest reptiles, whose modern descendants are included in the larger classification of the amniotes. | | | The pallial areas tend to be specialized into discrete regions in receipt of afferents from one particular sensory modality. | | | Structures in the diencephalon and telencephalon are also crucial to visual behavior in amniotes. |
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http://www.pigeon.psy.tufts.edu/avc/husband/avc2amnt.htm
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| | Dinosaur Origins |
| | Amniotes are fully terrestrial and lay eggs on land. | | | Amniotes not "tied to water" for purposes of reproduction. | | | Turtles have traditionally been considered anapsids, but they are now conidered modified diapsids. |
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http://users.tamuk.edu/kfjab02/dinos/VPDINOSAURS.htm
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| | Amphibians I |
| | Mammals have an amniote egg that has been modified somewhat to allow it to mature inside the mother. | | | Amphibians also differ from the amniote animals in that amniotes emerge from their eggs fully formed, resembling their parents, while young amphibians pass through a tadpole stage. | | | Amphibians have an egg with little yolk as food for the embryo, and have no protective shell, necessitating that it be laid in water to prevent it from drying out. |
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http://www.suite101.com/article.cfm/paleontology/33325
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| | Tetrapods and Amniotes |
| | Thus, before the development of the amniote egg, tetrapods had to return to the water to reproduce. | | | Require water to survive, and amphibians hatch as aquatic larvae (tadpoles). | | | The amniote egg is like a space ship for the embryo, containing all the necesary life support systems. |
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http://faculty.weber.edu/bdattilo/fossils/notes/amniot.html
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| | Pharyngula::Penis evolution |
| | Think about that… it hasn't been at all uncommon for female vertebrates to be untroubled by the absence of a penis in their mates, and apparently have preferred it that way. | | | The penis has a very simple job to do: to maintain sufficient stiffness to enter an orifice in the mate, and to deliver sperm. | | | Where different amniote lineages differ is in how they build their penis. |
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http://pharyngula.org/index/weblog/comments/penis_evolution
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| | Table of contents for Library of Congress control number 96041836 |
| | K.L.M. Martin and K.A. Nagy, Water Balance and the Physiology of the Amniote Transition. | | | G.V. Lauder and G.B. Gillis, Origin of the Amniote Feeding Mechanism: Experimental Analysis of Outgroup Clades. | | | Stewart, Morphology and Evolution of the Egg of Oviparous Amniotes. |
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http://www.loc.gov/catdir/toc/els032/96041836.html
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| | Neural induction: toward a unifying mechanism - Nature Neuroscience |
| | Strikingly, however, recipient ectoderm cells surrounding the site of transplantation cells were recruited to form an entire embryo with a fully developed secondary nervous system. | | | In chick, the node can induce neural tissue when transplanted to recipient embryos | | | At least two key aspects of the mechanism of specification of neural and epidermal cells are conserved in amphibian and amniote embryos. |
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http://www.nature.com/neuro/journal/v4/n11s/full/nn747.html
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| | The Amniote skull |
| | Amniotes = vertebrate animals with a special membrane around the egg | | | Amniote Phylogeny © 1996 Michel Laurin and Jacques A. Gauthier |
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http://www.kheper.net/evolution/glossary/skull.html
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| | Dr. Stuart S. Sumida |
| | Amniotes and their near relatives from the Paleozoic of southeastern Utah with comments on Lower Permian biogeography. | | | My research focuses on the structure, function, and evolution of fossil animals near the amphibian to amniote transition; animals that are found in sediments of late Pennsylvanian and early Permian age (approximately 270 to 300 million years old) -- animals nearly 100 million years older than the earliest known dinosaurs. | | | Biostratigraphic correlations between the Lower Permian of North America and central Europe using the first record of an assemblage of terrestrial tetrapods from Germany. |
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http://biology.csusb.edu/sumida.htm
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| | Hedgehog can drive terminal differentiation of amniote slow skeletal muscle BMC Developmental Biology, Volume 4 - ... |
| | Thus lack of Shh in somites leads to reduced early differentiation and delayed slow MyHC accummulation, as observed in chick limbs treated with anti-Hh antibodies. | | | Ventral midline Hedgehog (Hh) signals are also required for formation of the earliest muscle cells in the zebrafish embryo, the adaxial slow cells [[18,19], reviewed in [20]]. | | | However, the extent to which non-myogenic cells, myoblasts or differentiating myocytes are direct or indirect targets of Hh signalling is not known. |
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http://bmc.ub.uni-potsdam.de/1471-213X-4-9/text.htm
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| | Amniote Egg |
| | It has a shell to help prevent drying, and a series of membranes that surround the developing chick. | | | It is across the placenta that air, food, and wastes must be transferred. | | | The last name in that list, the mammals, may have surprised you since most mammals do not lay eggs, but the earliest mammals laid eggs, and a few, such as the duck-billed platypus still do. |
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http://www.biologycorner.com/worksheets/amniote-egg.html
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| | Donoghue Lab People |
| | Title: A comparative analysis of herbivory and amniote diversification in Recent terrestrial ecosystems. | | | Title: The origin of the cleidoic egg: does it explain the early proliferation Amniotes? | | | Sixth North American Paleontological Convention, Smithsonian Institution, Washington, D. Title: A comparative analysis of herbivory and amniote diversification in modern terrestrial ecosystems. |
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http://www.phylodiversity.net/donoghue/people/brian_pres.html
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| | What, you may ask, is an amniote? |
| | Amniotes reproduce using amniotic eggs (alternative but not quite accurate name: cleidoic eggs), or by structures derived from them (such as the amniotic sac and placenta of most mammals) |
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http://faculty.uca.edu/~benw/biol4402/lecture9b/sld002.htm
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| | Palaeos Vertebrates 190.400 Reptilomorpha: Cotylosauria |
| | The only other amniotes around were a few basal synapsids. | | | Characters: Little or no specialization along tooth row; $ maxilla separate from quadratojugal; $ single coronoid; some suborbital fenestra present; $ supinator process parallel to humeral shaft; $ 1 centrale in ankle; tail-based locomotion using lateral undulation; frequently bipedal; no glandular skin, uric acid waste, beta keratin. | | | We recommend a visit to this site which has some excellent images in which some of the listed characters can be seen. |
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http://www.palaeos.com/Vertebrates/Units/190Reptilomorpha/190.400.html#Reptilia
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| | Gut |
| | Fig 272 The gut of an amniote embryo showing its derivatives (Romer/Parsons, 1986). | | | Fig 12.1a Early amniote embryo in sagittal section (Hildebrand, 1988). | | | Fig 271A Early amniote embryo in sagittal section (Romer/Parsons, 1986). |
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http://www.lander.edu/RSFOX/308gutLec.html
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| | Amniote Phylogeny |
| | Relationships among the Anapsida (0 openings), Diapsida (2), and the extinct Synapsida (1 low) are uncertain: the absence of temporal openings in anapsids is sometimes considered to be the ancestral amniote condition. | | | Amniote groups are differentiated by the number and position of temporal openings in the skull. |
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http://www.mun.ca/biology/scarr/Phylogeny_of_Amniota.htm
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| | Evolution of the Avian Visual System |
| | Such a perspective provides insights on the capabilities and limitations of avian vision, and how different species utilize information to navigate, forage, mate, et cetera. | | | Characteristics which appear similar in structure and/or function in two organisms may derive from the condition of the presumed ancestor of the two forms. | | | For example, some general features of reptilian brains (the closest relatives of modern birds) may indicate the condition found in ancestral avian forms. |
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http://www.pigeon.psy.tufts.edu/avc/husband
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| | Bio 211 Lecture 3, Fall 1999 |
| | Amniotes radiated into most terrestrial habitats by the late Carboniferous (300 mya), replacing non-amniotes (which persisted in aquatic environments) | | | The splits among the different amniotes occurred early in their evolution (mid-Paleozoic), with early mammals (synapsids) being the first to split away from the sauropsids (reptiles and birds) | | | The basic vertebrate design and evolution II: Non-amniote evolution and the subsequent emergence of modern extant vertebrate lineages. |
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http://www.lclark.edu/~clifton/landverts/outlines/bio211lect3.htm
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| | Amniote origins? |
| | A group of early tetrapods, the anthracosaurs, include amniote relatives or ancestors. | | | ìLizzieî, from 350 million-year-old rocks of Scotland, is the oldest probable amniote |
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http://faculty.uca.edu/~benw/biol4402/lecture9b/sld005.htm
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| | Amniote Tree of Life |
| | Amniote Phylogeny presented as a "Tree of Life" | | | Compare this tree with a conventional phylogenetic diagram of the same group. |
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http://www.mun.ca/biology/scarr/Tree_of_Life_for_Amniota.htm
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| | Amniote Group |
| | Amniotes originated from the Amphibian group, who lade there embryos in the water. | | | AMNIOTIC FLUID, which is suppose to simulate the embryos own pond is only found in this group. | | | This diagram shows the embryo (top) within aquatic medium. |
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http://hoopermuseum.earthsci.carleton.ca/birds/pg2pt1.htm
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| | Amniote gill bars - EvoWiki |
| | The embryos of amniotes (reptiles, birds, mammals) go through a phase where they have gill bars and gill pouches, though not functional gills; the previously-mentioned aorta aortic arches are to supply blood to these would-be gills. |
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http://wiki.cotch.net/index.php/Amniote_gill_bars
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| | amniote : Definition |
| | Search for amniote in these other databases too |
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http://www.everythingbio.com/glos/definition.php?ID=2792
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| | SKINKS, CUCKOOS, AMNIOTE EGG etc |
| | Skulan, J. Has the importance of the amniote egg been overstated? | | | Every now and again someone challenges the cherished views that we have all become familiar with. |
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http://dml.cmnh.org/2000Oct/msg00493.html
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| | †Diadectomorpha |
| | Lee, M. and Spencer, P. S., 1997: Crown-clades, key characters and taxonomic stability: When is an amniote not an amniote? | | | in Sumida, S. and Martin, K. M., 1997: Amniote origins: Completing the transition to Land. | | | inSumida, S. and Martin, K. M., 1997: Amniote origins: Completing the transition to Land. |
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http://www.fmnh.helsinki.fi/users/haaramo/Metazoa/Deuterostoma/Chordata/Amphibia/Reptiliomorpha/Diadectomorpha.htm
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| | Images for Chapter 10 Early Amniotes and Thermoregulation |
| | Images for Chapter 10 Early Amniotes and Thermoregulation | | | Theriodonts dominated the early Late Permian of Russia. | | | Comparison of skull characteristics of major amniote groups |
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http://www-geology.ucdavis.edu/~cowen/HistoryofLife/CH10images.html
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| | amniote - OneLook Dictionary Search |
| | Tip: Click on the first link on a line below to go directly to a page where "amniote" is defined. | | | amniote : Encarta® World English Dictionary, North American Edition [home, info] | | | We found 14 dictionaries with English definitions that include the word amniote: |
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http://www.onelook.com/?w=amniote&ls=a
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| | Development and Evolution of Amniote Integuments |
| | Adaptation to the land: The skin of reptiles in comparison to that of amphibians and endotherm amniotes (p 12-41) Lorenzo Alibardi | | | Adaptation to the sky: Defining the feather with integument fossils from mesozoic China and experimental evidence from molecular laboratories (p 42-56) Cheng-Ming Chuong, Ping Wu, Fu-Cheng Zhang, Xing Xu, Minke Yu, Randall B. Widelitz, Ting-Xin Jiang, Lianhai Hou | | | Development and evolution of the amniote integument: Current landscape and future horizon (p 1-11) Cheng-Ming Chuong, Dominique G. Homberger |
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http://www-hsc.usc.edu/~cmchuong/JEZtableofcontents.htm
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| | MSN Encarta - Dictionary - amniote definition |
| | Click here to search all of MSN Encarta | | | Search for "amniote" in all of MSN Encarta |
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http://encarta.msn.com/encnet/features/dictionary/DictionaryResults.aspx?refid=1861585218
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