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A Guide to the Orders of Trilobites

A Guide to the Orders of Trilobites
The Trilobite of the Month for April 2014 is a distinctive representative of the Order Asaphida, in the primitive superfamily Anomocaroidea. Like many members of the Asaphida, there is evidence of a very wide doublure, most apparent along the margins of both the cephalon and the pygidium. Remarkable concentric terrace ridges are apparent, running parallel to the anterior and posterior margins. I particularly enjoy the circular curves of the anterior facial sutures which converge at the signature anterior median ventral suture characteristic of many of the Asaphida. This image is courtesy of Dan Bowden. Images like this help explain why trilobites are one of the best-known and appreciated groups of prehistoric animals.

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Biological classification The hierarchy of biological classification's eight major taxonomic ranks. Intermediate minor rankings are not shown. Modern biological classification has its root in the work of Carolus Linnaeus, who grouped species according to shared physical characteristics. These groupings have since been revised to improve consistency with the Darwinian principle of common descent. With the introduction of the cladistic method in the early 20th century, formalized by Willi Hennig in the mid-20th century, phylogenetic taxonomy in which organisms are grouped purely on inferred evolutionary relatedness (based either on classical evidence of morphology, chemistry, physiology, ecology or molecular evidence or both) has become common in biology.[1] Molecular phylogenetics, which uses DNA sequences as data, has driven many recent revisions and is likely to continue doing so. Biological classification belongs to the science of biological systematics.

japanese garden in portland photo Random photo Submit your photo Stumble Thru nature photography Image of the Day: The Oldest Supernova Explosion Ever Detected Astronomers have discovered the oldest and farthest supernova ever detected -- a massive star that exploded 11 billion years ago. Scientists compared several years of images taken from one portion of the sky, which let them look for objects that changed in brightness over time -- “subtracting” the changes from the original image –- which erased the entire galaxy save for the supernova, which had changed. “What we’re looking for are things that were there one year, but which weren’t there the next,” said Mark Sullivan, an astronomer from the University of Oxford in the UK and one of the authors of the study, in a separate BBC report. Prior to this discovery, NASA’s Swift Observatory had detected a 13-billion-year-old gamma-ray burst, most likely from a supernova near the beginning of the Universe.

Introduction to Trilobites This is NOT the HOME PAGE of this site. Please click here to go to the true start page. last revised 15 May 2014 Trilobites are remarkable, hard-shelled, segmented creatures that existed over 520 million years ago in the Earth's ancient seas. They went extinct before dinosaurs even came into existence, and are one of the key signature creatures of the Paleozoic Era, the first era to exhibit a proliferation of the complex life-forms that established the foundation of life as it is today. Although dinosaurs are the most well-known fossil animals, trilobites are also a favorite among those familiar with Paleontology (the study of the development of life on Earth), and are found in the rocks of all continents.

The Top 50 'Pictures of the Day' for 2011 Every day at 5pm the Sifter posts the Picture of the Day. Below you will find a collection of the Sifter’s Top 50 from 2011. It’s hard to imagine the year is almost over, time seems to fly faster each successive year so it’s fun to take a moment and look back at the year that was. Resurrecting the Woolly Mammoth? Scientists Plan to Clone the Extinct Creature Good news for anyone who wishes we could revert to prehistoric times, or really, anyone who thinks woolly mammoths are awesome. Scientists in Asia have announced plans to recreate the giant creature that stomped around the Earth some 4,500 years ago. On Tuesday, scientist Hwang Woo-suk of South Korea’s Sooam Biotech Research Foundation signed an agreement with Vasily Vasiliev of Russia’s North-Eastern Federal University to clone a mammoth, AFP reports.

Fauna Simplified schematic of an island's fauna - all its animal species, highlighted in boxes. Zoologists and paleontologists use fauna to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. Etymology[edit] Subdivisions of fauna[edit] Dream Worlds Revealed On Canvas Along with some magnificent dreams, Jacek Yerka finds inspiration for his masterful paintings from his childhood memories: the places, remembered feelings and smells of 1950′s Poland. He studied fine art and graphic design before becoming a full time artist in 1980… and we’re glad he did. His paintings will take you through incredible worlds of imagination, bending reality in captivating and clever ways fit to inspire a novel or film.

Introduction 1. INTRODUCTION A typical ichthyosaur looks like this (see note for derivation and pronunciation of "ichthyosaur", as well as its usage in this page). Yes, just like a fish. 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:

Utah's Cambrian Life - Evolution and Biogeography of Burgess Shale Type Fossils The purpose of this web site is to provide an overview of the diverse Cambrian life that flourished in an ancient sea that covered what is now Utah over 500 million years ago. Evidence of Utah's Cambrian life is revealed by an exceptionally well-preserved fossil record of soft-bodied life forms that rarely stand any chance of becoming fossils. The focus of this web site is to showcase these special fossils, as well as to describe their geological and evolutionary context. Many of the fossils shown on this web site were collected by the Gunther Family of Utah, who were instrumental in bringing these fossils to light. University of Kansas Professor Emeritus Richard Robison, along with colleagues, was a pioneer in describing and documenting these amazing fossils. The research presented on this web site was supported in part by the National Science Foundation (Grant EAR-0518976 to Bruce Lieberman, Department of Geology and Natural History Museum, University of Kansas ).

Index fossil Examples of index fossils Index fossils (also known as guide fossils, indicator fossils or zone fossils) are fossils used to define and identify geologic periods (or faunal stages). They work on the premise that, although different sediments may look different depending on the conditions under which they were laid down, they may include the remains of the same species of fossil. If the species concerned were short-lived (in geological terms, lasting a few hundred thousand years), then it is certain that the sediments in question were deposited within that narrow time period. The shorter the lifespan of a species, the more precisely different sediments can be correlated, and so rapidly evolving types of fossils are particularly valuable. The best index fossils are common, easy-to-identify at species level, and have a broad distribution—otherwise the likelihood of finding and recognizing one in the two sediments is minor.[1]

Photos of Sakurajima volcano 25 Feb 2010 On a recent visit to Japan, alien landscape photographer Martin Rietze captured some spectacular images of Sakurajima volcano in Kagoshima prefecture. Multiple lightning flashes caused by fast moving fine ash Whale-eating sea monster uncovered in Peru Leviathan melvillei chomps down on a baleen whale. HIT PLAY, above, the see its fossilised teeth. Three lower teeth (a,b,c) of Leviathan melvillei compared to teeth of the modern sperm whale Physeter macrocephalus (d) and the modern killer whale Orcinus orca (e). Credit: G.