background preloader

A Guide to the Orders of Trilobites

A Guide to the Orders of Trilobites

Préhistoire Préhistoire Une page pour visualiser d'un seul coup d'oeil les grands événements de la Préhistoire, son histoire, son étude, et aussi celle de l'Homme et de ses ancêtres : les hommes préhistoriques. Préhistoire, une histoire récente... Un peu d'histoire de la Préhistoire... Cela fait maintenant presque deux siècles que l'homme étudie cette période chronologique qui s'étend sur plusieurs millions d'années : la Préhistoire. Ce ne fut d'abord qu'une marotte qui occupait le temps libre de passionnés. Ils collectionnaient, entassaient sans toujours comprendre que ces objets ou ossements étaient vieux de dizaines de milliers d'années, ou plus. La vérité vient de la géologie Les études géologiques commencent alors à faire reculer l'âge de la Terre. Histoire de la Terre Les théories de l'évolution Préhistoire - les grandes avancées Le schéma ci-dessous vous présente les avancées majeures de la préhistoire, ou du moins celles dont on a pu trouver et identifier les traces ! Schéma Copyright Neekoo

Strange Science: The Rocky Road to Modern Paleontology andBiology Internet Sites généraux sur l'évolution Evolution de l'origine de la vie aux origines de l'homme : Un dossier du centre National de la Recherche Scientifique aborde le sujet par une dizaine d'articles écrits par des spécialistes. Ne râter pas la videothèque et les arbres phylogénétiques. L'évolution le grand récit du vivant : Les Vidéo et les documents d'un cycle de conférences organisées par le Citée des Sciences en 2007. Paleontologia electronica : une revue de paléontologie en ligne, avec des images, bien sur, mais aussi des animations. Planète Terre par P. CMP Web Time Machine : Une bible! PALAEOS: The Trace of Life on Earth : Le cladogramme du monde vivant. Paléontologie humaine De superbes réalisations du Ministère de la Culture Tautavel, la Caune de l'Arago La Grotte Chauvet La grotte de Lascaux Ce site fourmille d'articles, de dossiers et d'informations actualisées sur l'histoire de la lignée humaine, l'art préhistorique et la théorie de l'évolution. Trilobites Ammonites Ammonites du Jurassique.

Crocodiles and Turtles of Borneo Spiny Turtle (Heosemys spinosa) 22 cm Emys spinosa J. E. Gray. 1831. Heosemys spinosa Type: Untraced in The Natural History Museum, London, the repository of most of J. Identification: The young ones of this turtle resemble pin cushions, with greatly expanded marginals with distinct spines that disappear or become less obvious with growth, or through wear and tear. Natural history: The species inhabits forests, usually in the uplands, and may be found far from water. Distribution: This turtle ranges from southern Myanmar, through Thailand and Peninsular Malaysia and Singapore to the islands of Sumatra, Borneo and the Natunas.

Paleoartistry Cold Water Images, Photography by Kawika Chetron - Green sea turtle, Chelonia mydas Green sea turtles (Chelonia mydas) seem to really enjoy taking time out to get cleaned. These gold-ring surgeonfish (Ctenochaetus strigosus) and yellow tangs (Zebrasoma flavescens) eek out a living nibling at algae that grows on the reef. You can imagine their excitment when a turtle who's been out at sea arrives sporting a shell with a lush carpet of algal growth. This turtle has an injured flipper. Monofilament fishing line and other refuse create entanglement hazards for a wide variety of marine animals, turtles included. Green sea turtle (Chelonia mydas) and orangespine unicornfish (Naso lituratus). This green sea turtle (Chelonia mydas) appears to be giving me a one-flipper salute. Green sea turtle (Chelonia mydas). Green sea turtle (Chelonia mydas), gold-ring surgeonfish (Ctenochaetus strigosus) and yellow tangs (Zebrasoma flavescens). Home

UCMP Web Time Machine Online exhibits Geologic time scale Take a journey back through the history of the Earth — jump to a specific time period using the time scale below and examine ancient life, climates, and geography. You might wish to start in the Cenozoic Era (65.5 million years ago to the present) and work back through time, or start with Hadean time (4.6 to 4 billion years ago)* and journey forward to the present day — it's your choice. [Note: "mya" means "millions of years ago"] Ways to begin your exploration: Use the links in the "time machine" below and explore a specific period that interests you.Read more about the geologic time scale, its origins and its time divisions.Find out more about plate tectonics, an important geological concept in any time period!

Living in a Landscape of Fear: How Predators Impact an Ecosystem: Scientific American Editor's Note: The following is an excerpt from Cristina Eisenberg's book The Wolf’s Tooth. A doe burst out of the forest and tore across the meadow, two wolves in close pursuit. This drama unfolded not twenty feet from where my young daughters and I knelt in our garden peacefully pulling weeds, our pant legs wet with morning dew. We live at the base of a mountain in northwestern Montana. Landscapes shape us and speak to us on a primal level. Humans also have a primal relationship with large predators. I marked one track, and from it we located others laid out in a gallop pattern. In the fifteen years since wolves returned, the deer had been behaving differently—more wary, not standing in one place, eating all the shrubs down to nothing. The Green World Hypothesis In 1969 Loren Eiseley wrote an evocative story, "The Star Thrower," about a man who walked the strip of wet sand that marks the tide's ebb and flow, tossing sea stars that had washed ashore back into the ocean.

Le site des dinosaures... Edward Wilson The classic article, published 2 decades ago by one of the world's great biologists & humanists Imagine that on an icy moon of Jupiter - say Ganymede - the space station of an alien civilization is concealed. For millions of years its scientists have closely watched the earth. Because their law prevents settlement on a living planet, they have tracked the surface by means of satellites equipped with sophisticated sensors, mapping the spread of large assemblages of organisms, from forests, grasslands and tundras to coral reefs and the vast planktonic meadows of the sea. The watchers have been waiting for what might be called the Moment. It was all but inevitable, the watchers might tell us if we met them, that from the great diversity of large animals, one species or another would eventually gain intelligent control of Earth. Darwin's dice have rolled badly for Earth. The human species is, in a word, an environmental abnormality. The rules have recently changed, however.

How To Heat Up Your Room Using Just a Candle: Kandle Heeter! | Green Electronics This heater is a multi-core steel and ceramic radiator assembly, suspended above the candle on a solid steel stand. The radiator absorbs and concentrates the thermal energy of the candle and converts it into dry radiant space heat. If you burn candles, now you can add their heat to your home or office. There is also an “electric candle” option that uses a 60 watt quartz halogen lamp; that works out to about 6 cents for 10 hours of “burn” time. “Steel has the ability to approach the temperature of its heat source,” says the inventor, “so the solid steel inner core will go as high as 550° Fahrenheit. The simple elegant design has no moving parts. What’s new for 2008 is an “electric candle” option that takes advantage of the fact that 90% of the energy that goes into an incandescent lamp is “wasted” as heat. The electric candle is pictured below: The Kandle Heeter Candle Holder is available on Doyle Doss’s website, for $29.95.

Oceanus : Fertilizing the Ocean with Iron By Hugh Powell :: Originally published online : In print Vol. 46, No. 1, Jan. 2008 “Give me half a tanker of iron, and I’ll give you an ice age” may rank as the catchiest line ever uttered by a biogeochemist. The man responsible was the late John Martin, former director of the Moss Landing Marine Laboratory, who discovered that sprinkling iron dust in the right ocean waters could trigger plankton blooms the size of a small city. In turn, the billions of cells produced might absorb enough heat-trapping carbon dioxide to cool the Earth’s warming atmosphere. Never mind that Martin was only half serious when he made the remark (in his “best Dr. Strangelove accent,” he later recalled) at an informal seminar at Woods Hole Oceanographic Institution (WHOI) in 1988. At the time, ice-core records suggested that during past glacial periods, natural iron fertilization had repeatedly drawn as much as 60 billion tons of carbon out of the atmosphere. Not as simple as it sounds But is it legal?

researcher collaborates on important study of how ocean dead zones are shrinking habitat for blue marlins, other tropical billfish and tunas :: NOAA Fisheries Blue marlins and many other billfish are high energy fish that need large amounts of dissolved oxygen. By comparing the movement of the blue marlins and the location of low-oxygen areas, the study shows that blue marlins venture deeper when dissolved oxygen levels are higher and remain in shallower surface waters when low dissolved oxygen areas encroach on their habitat from below, squeezing them into surface waters. December 9, 2011 The science behind counting fish in the ocean to measure their abundance has never been simple. A new scientific paper authored by NOAA Fisheries biologist Eric Prince, Ph.D., and eight other scientists shows that expanding ocean dead zones – driven by climate change – have added a new wrinkle to that science. In the December 4 paper published in the scientific journal Nature Climate Change, these scientists sound an alarm that expanding ocean dead zones are shrinking the habitat for high value fish such as marlins in the tropical northeast Atlantic Ocean.

Remote Antarctic island is 'richer in biodiversity than the Galapagos' Antarctica's remote South Georgia Island boasts 90 percent of the world's fur seals, half of the world's elephant seals, is navigated by vast populations of blue whales, sperm whales and killer whales, and has beaches that can be packed shoulder-to-shoulder with nesting penguins. In total, it contains nearly 1,500 recorded species, many of which are found nowhere else on Earth. It's difficult to believe that until recently, this biological treasure was believed to be nothing more than an "inhospitable lump of rock." In fact, researchers now believe that South Georgia Island contains more species than anywhere else in the Southern Ocean, and may be the most biologically diverse remote island in the world — even more diverse than the storied Galapagos Islands, according to the Independent. "It shows you don't have to be a tropical island or in a hot part of the world to support a lot of marine life. The types of marine life around the island vary immensely.