Fossils Fossils Acanthostega gunnari is an extinct amphibian tetrapod species, among the first animals to have recognizable limbs. It appeared in the Upper Devonian (Famennian) and is a candidate for being one of the first vertebrates to be capable of coming onto land. It had eight fingers on each hand, the hindlimbs had seven digits, it lacked wrists, and was generally poorly adapted to come onto land. The limbs could not support the animal's weight. Therefore, paleontologists surmise that it was probably the first lobe-finned fish to come onto land. ...more on Wikipedia about "Acanthostega"
Acritarchs are small organic structures found as fossils. In general, any small, non- acid soluble (i.e. non carbonate, non-silicate) organic structure that can not otherwise be accounted for is an acritarch. Most acritarchs are surely remains of single celled lifeforms. They are found in sedimentary rocks from the present back into the Precambrian. They are easily isolated from limestones with hydrochloric acid, and can also be isolated from silica rich rocks using hydrofluoric acid. They are excellent candidates for index fossils to be used for formation dating in the Palaeozoic and when other fossils are not available. They are also useful for palaeoenvironmental interpretation. Acritarchs include the remains of several quite different kinds of organisms including bacteria and dinoflagellates. The nature of the creatures associated with older acritarchs is generally not clear, though many are probably related to unicellular marine algae. ...more on Wikipedia about "Acritarch"
Amber is a fossil resin much used for the manufacture of ornamental objects. Although not mineralized it is sometimes considered and used as a gemstone. Most of the world's amber is in the range of 30–90 million years old. ...more on Wikipedia about "Amber"
Anomalocarids (meaning "odd shrimp") are a group of very early marine animals known from fossils found in Cambrian deposits in China, North America, and Australia. Anomalocarids are the largest Cambrian animals known (some Chinese forms grew up to 2 meters in length), and most of them were probably active carnivores (although recent thought posits one genus, Laggania, as a plankton-eating animal). ...more on Wikipedia about "Anomalocarid"
The Archaeocyatha, also called Archaeocyathids, were sessile, reef-building marine organisms that lived during the Lower Cambrian period (500-600 million years ago). All species being extinct, they are known only from fossils. ...more on Wikipedia about "Archaeocyatha"
Arkarua is a small, Precambrian disk-like fossil with a raised center, a number of radial ridges on the rim, and a five-pointed central depression marked with radial lines of 5 small dots from the middle of the disk center. The species Arkarua adami is 3 to 10mm across. Because of the five-fold symmetry, Arkarua has been proposed as a possible precursor to the Echinoderms. Some claim it is not only an echinoderm, but is specifically an Edrioasteroid. A few Edrioasteroids are reported from the Lower Cambrian of California and Newfoundland as well as the middle Cambrian of British Columbia in Canada. Arkarua is known only from the Ediacaran beds of South Australia. ...more on Wikipedia about "Arkarua"
Ausia is a curious Precambrian-age fossil that basically consists of a hollow cylinder taping to a cone on one end. The surface is covered with circular rows of depressions("windows") that taper into ovals toward the conical point. Ausia Fenestrata, named for the town of Aus in Namibia, is the only known Vendian animal with pores. Still, there is some question as to whether these pores completely penetrate the animal's wall. It may be a primitive sponge. ...more on Wikipedia about "Ausia"
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Aysheaia pedunculata is a soft-bodied, caterpillar-shaped organism average body length of 1-6 cm. They are known from fossils found in the middle Cambrian Burgess shale of British Columbia. Similar forms are known from the lower Cambrian Maotianshan shales of China. Aysheaia has ten body segments, each of which has a pair of spiked, annulated legs. The animal is segmented, and looks somewhat like a bloated caterpillar with a few spines added on -- including six finger-like projections around the mouth and two grasping legs on the "head." Based on its association with sponge remains, it is believed that Aysheaia was a sponge grazer and may have protected itself from predators by seeking refuge within sponge colonies. Aysheaia probably used its claws to cling to the sponge. ...more on Wikipedia about "Aysheaia"
Biostratigraphy is the science of dating rocks by using the fossils contained within them. Usually the aim is correlation, that is, demonstrating that a particular horizon in one geological section represents the same period of time as another horizon at some other section. The fossils are useful because sediments of the same age can look completely different because of local variations in the sedimentary environment. For example, one section might have be made up of clays and marls while another has more chalky limestones, but if the fossil species recorded are similar, the two sediments are likely to have been laid down at the same time. ...more on Wikipedia about "Biostratigraphy"
Bivalves are molluscs belonging to the class Bivalvia. They typically have two-part shells, with both parts being more or less symmetrical. The class has 30,000 species, including scallops, clams, oysters and mussels. Other names for the class include Bivalva, Pelecypoda, and Lamellibranchia. ...more on Wikipedia about "Bivalvia"
Blastoids (class Blastoidea) are an extinct type of stemmed echinoderm. Often called "sea buds," blastoid fossils look like small hickory nuts. They originated, along with many other echinoderm classes, in the Ordovician period and reached their greatest diversity in the Mississippian period. Blastoids persisted until their extinction at the end of Permian, about 250 million years ago. Although never as diverse as their contemporary relatives, the crinoids, blastoids are quite common fossils, especially in many Mississippian-age rocks.They can be found in Illinois, Kentucky, and Indiana. ...more on Wikipedia about "Blastoid"
Blue Amber is a rare coloration of amber. It most commonly is found in the Dominican Republic and well regarded by collectors for its value. ...more on Wikipedia about "Blue Amber"
Brachiopods (from Latin bracchium, arm + New Latin -poda, foot) make up one of the major animal phyla, Brachiopoda. Also known as lamp shells, they are sessile, two-shelled, marine animals that somewhat resemble pelecypod mollusks (i.e. "clams") externally but are quite different internally. Unlike bivalves, which have a left shell and a right shell, brachiopods are always bilaterally symmetric, although the top and bottom shells usually differ in shape. The shells may be either phosphatic or calcaerous. Some fossil forms also had elaborate spines. ...more on Wikipedia about "Brachiopod"
Bryozoans are tiny colonial animals that generally build stony skeletons of calcium carbonate, superficially similar to coral. They are also known as moss animals or sea mats. They generally prefer warm, tropical waters but are known to occur worldwide. There are about 5,000 living species, with several times that number of fossil forms known. ...more on Wikipedia about "Bryozoa" http://www.shortopedia.com never sleeps. Fossils
Canadia is an extinct polychaete annelid known from fossils found in the Burgess Shale formation of British Columbia. ...more on Wikipedia about "Canadia"
Charnia is the genus name given to a frond-like Precambrian lifeform with segmented ridges branching alternately to the right and left from a zig-zag medial suture. It strongly resembles a chestnut leaf. There are two species, Charnia masoni, discovered in 1957 in Bradgate Park, Leicestershire and Charnia wardi, discovered in 1978 in southeast Newfoundland. The genus was named after Charnwood Forest (the area in which the first species was found). It was originally interpreted as an algae (Ford) or a sea pen (Glaessner). One modern interpretation is that Charnia is a Vendazoan built with unipolar iterations of one cell family. ...more on Wikipedia about "Charnia"
Chitinozoa (English singular: chitinozoan, plural: chitinozoans) are a group of flask-shaped marine microfossils (50-2000 micrometres) which appear dark or almost opaque when viewed using a light microscope. They are used as stratigraphic markers in biostratigraphy from Ordovician, Silurian to Devonian. They have no neck (Family Desmochitinidae) , a badly defined neck/flexure (Family Conochitinidae) or a well defined neck/flexure (Family Lagenochitinidae). The chamber is closed by a operculum (Order Operculatifera) or a prosome (Order Prosomatifera). ...more on Wikipedia about "Chitinozoa"
Cloudinids (Cloudinia) are an extinct animal phylum that formed small tubelike or conical fossils consisting of "cup-in-cup" segments of calcareous material. What the animal itself looked like is still unknown. Cloudinids were widely distributed. They are quite abundant in some deposits. They are the earliest common animal form with a calcareous shell. The name Cloudinia honors 20th Century geologist and paleontologist Preston Cloud. ...more on Wikipedia about "Cloudinid"
A compression fossil is a fossil preserved in sedimentary rock that has undergone physical compression. While it is uncommon to find animals preserved as good compression fossils, it is very common to find plants preserved this way. The reason for this is that physical compression of the rock often leads to distortion of the fossil. ...more on Wikipedia about "Compression fossil"
Conodonts are extinct worm-like forms with distinctive conical or multi-denticulate teeth made of apatite (calcium phosphate). The animals are sometimes referred to as conodontophora ("bearers of conodonts"), taking the word "conodont" to refer to the teeth themselves, but the strictly correct name for the animal group is 'Conodonta'. These tiny teeth are quite common in Paleozoic rocks and sands (250 to 500 million years old), but body fossils were not found until the early 1980s. The teeth (or more formally "elements") show complex, specialized structures, and survived through the ages and the fossilization process due to their resilient phosphatic chemical composition. ...more on Wikipedia about "Conodont"
Coprolites are fossilized feces, or animal dung. They form an important class of objects studied in the field of paleontology. ...more on Wikipedia about "Coprolite"
Cretoxyrhina mantelli, the "Jaws of the Cretaceous", was a shark that lived in the Cretaceous period, about 100 million years ago. C. mantelli grew up to 5.5 meters long, and is known from several nearly complete skeletal fossils. ...more on Wikipedia about "Cretoxyrhina mantelli"
Crinoids, also known as "sea lilies" or "feather-stars", are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). They live both in shallow water and in depths as great as 6000 meters. Crinoids are characterized by a mouth on the top surface that is surrounded by feeding arms. Although the basic echinoderm pattern of five-fold symmetry can be recognized, most crinoids have many more than five arms. Crinoids usually have a stem used to attach themselves to a substrate, but many live attached only as juveniles and become free-swimming as adults. There are only a few hundred known modern forms, but crinoids were much more numerous both in species and numbers in the past. Some thick limestone beds dating to the mid- to late- Paleozoic are entirely made up of disarticulated crinoid fragments. ...more on Wikipedia about "Crinoid"
Cyclomedusa is an ancient circular fossil with a circular bump in the middle and having as many as 5 circular growth ridges around it. Many specimens are small, but specimens in excess of 20cm are known. The concentric disks are not necessarily circular, especially when adjacent individuals interfere with each other's growth. Many radial segment lines -- somewhat pineapple-like -- extend across the outer disks. A few specimens show what might be a stem extending from the center in some direction or other. ...more on Wikipedia about "Cyclomedusa"
Diatomaceous earth, also known as diatomite, kieselguhr, kieselgur, and Celite, is a naturally occurring, soft, chalk-like, sedimentary rock mineral that is easily crumbled into a fine white to off-white powder. This powder has an abrasive feeling similar to pumice powder and is very light-weight due to its high porosity. It is made primarily of silica and consists of fossilized remains of diatoms, a type of hard-shelled algae. It is used as a filtration aid, as a mild abrasive, as a mechanical insecticide, as an absorbent for liquids, as cat litter, and as a component of dynamite. ...more on Wikipedia about "Diatomaceous earth"
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