Conodonts are tiny, tooth-like, extinct microfossils that lived during the late Cambrian to the late Triassic period. They ranged anywhere from .22mm to 6 mm in length and were found mostly in marine sedimentary rocks of the Paleozoic age.
Conodonts are composed of calcium phosphate and range in color from translucent light color to a black. Conodonts are believed to have been small marine invertebrates living in the open oceans and coastal waters. Although Conodonts remained a puzzle for years, they were they were Conodonts are classified in the class Conodonta which includes jawless fish through to jawed vertebrates in the Phylum Chordota. Clearly very little can be stated about the possible life cycles of conodonts since the host organism
of conodonts is extinct. Conodonts are outspread, and identical or related species are found in many parts of the world. Black shales and limestones are rich in conodonts, but they also appear in sedimentary rocks. The process by obtaining conodonts is by dissolving limestone in 15 percent acetic acid. In this acid, conodonts are insoluble and the remains are collected, and put into a heavy liquid, bromoform, in which conodonts sink. Then they are studied and analyzed. At first, conodonts were discovered in Russia during the mid 19th century and were acknowledged as crucial to rock dating, and soon after more countries followed. The succession of conodonts serve as reference standards. The conodonts obtained from similar rocks from someplace or another can then be compared with these and correlations can be made.
Fox, R. 2001. Invertebrate Anatomy OnLine: Artemia Franciscana. Lander University. http://webs.lander.edu/rsfox/invertebrates/artemia.html, retrieved February 13, 2011.
W. H. Freeman and Company, New York. 2) http://www.trueauthority.com/dinosaurs/about.htm 3) Dr. Robert Riesz, University of Toronto, “Ceratopsia and Ornithopoda” http://www.erin.utoronto.ca/w
Because of its size and abundance, T. californicus is commonly regarded as the insect of the sea. This creature is generally very small, from 1-3 mm in size as adults. They are cylindrically shaped, and have a segmented body (head, thorax, abdomen) though no noticeable division between body regions (Powlik 1966). Each segment of the body has a pair of legs. They use their 'legs' to propel themselves through the water in short rapid jerks. They have 2 pairs of long feathered antennae, a chitin us exoskeleton and a single eye in the middle of their head, this simple eye can only differentiate between light and dark.
Mojetta wrote about prehistoric sharks, and the history of these creatures. According to Angelo Mojetta, author of Sharks, Cladoselache genus, one of the first prehistoric sharks, was buried in sediment that kept it preserved. Unlike other sharks, Cladoselache genus had a circle of tiny plates around it’s eyes for protection against it’s victim’s attempts to fight back. These sharks lived over 400 million years ago. Sharks of the past could mostly be identified by their teeth, because shark’s bodies are made of cartilage. Another shark that was focused on was called, Stethacanthus. This shark had a very unique look. Stethacanthus had a brush like decoration on the top of it’s head, and an extra fin like part that had the same bristle like decorations on it. These characteristics were thought to be used as suction cups, to hitch rides from larger fish. One of the most famous sharks that looks like an over...
The Great Barrier Reef is home to a remarkable number of organisms. The coral itself is made up of the skeletons of tiny, flowerlike water animals called polyps, held together by a limestone substance produced by a type of algae. Hundreds...
Cannibalism is a long-standing taboo in our society; the thought of humans preying on other humans for a food source disgusts and astounds us. Though the practice is not common amongst modern day humans there is some evidence to suggest that ancient humans resorted to such measures, and a recent discovery in Madagascar attests to the possibility that some carnivorous dinosaurs fed on their own species (Perkins, 2003).
When the word Shark comes to mind most people think of a monster that feeds on humans and is an enemy of all living beings. Contrary to popular belief less than 10 percent of sharks are known to attack humans unprovoked. Sharks are classified under the class of Chondrichthyes, which is fish that have characteristics of a skeleton made of cartilage, jaws, paired fins, and paired nostrils. The superorders are divided into two groups, which are Batoidea that have rays and their relatives and Selachii, which are sharks. Scientists have found isolated spines, teeth, and scales that appeared 350 to 400 million years ago in the Devonian Period known as "Age of Fishes". Most modern sharks have evolved 100 million years ago when dinosaurs lived on earth. (Matthews, 1989) Sharks have been known to inhabit tropical and temperate seas as well as some cold and polar seas. Migration of sharks is poorly understood due to not all species migrating. And in the species that do migrate the distance may be short or long and is based on availability of the food and environmental cycles. One American biologist Eugenie Clark is the world leader in shark study, she was the first person to learn how sharks behaved in captivity and how well sharks had the ability to understand.
Rock layers are like a portal through time, they show how animals looked in past and evolved through time. In these layers we see fossils, “petrified” and “preserved” forms of old organisms (Google). Scientists have seen and uncovered many different fossils and some have looked similar but from different depths in the layers. Scientists have found fossils of fish, reptiles, amphibians, mammals, birds, today’s mammals, and dinosaurs. They have grouped these fossils into three periods based on how deep in the earth they were found. These periods are the Paleozoic, Mesozoic, and Cenozoic periods. The Paleozoic period has the fossils that are the farthest down in the layer. These fossils include fish, amphibians, and reptiles. The Mesozoic period is contains all things dinosaur and is in between the Paleozoic and Cenozoic periods. Finally, the Cenozoic period contains the fossils of Mammals, birds, and today’s mammals, such as humans.
In absence of calcium carbonate, coral and shellfish can’t survive. The ecosystem of ocean depends on these organisms because they offer a large source of food at the bottom of the food chain. They need to be abundant in order t...
The Jurassic period was the second segment of the Mesozoic Era. It occurred from 199.6 to 145.5 millions years ago, following the Triassic Period and preceding the Cretaceous Period. During the Jurassic Period, the supercontinent Pangaea split apart. Laurentia, the northern half, made up what would eventually form North America and Eurasia. The creation of these opened basins for the central Atlantic and the Gulf of Mexico. The southern half, Gondwana, drifted into an eastern segment that now forms Antarctica, Madagascar, India, and Australia, and a western portion that forms the present Africa and South America. This rifting, along with generally warmer global temperatures, allowed for diversification and dominance of the reptiles known as dinosaurs. Along with dinosaurs, several different types of life and rock formations emerged during the Jurassic period.
They ruled the world before the time of the dinosaurs, from the Cambrian Period to the
...nder, C., Tsai, C., Wu, P., Speer, B. R., Rieboldt, S., & Smith, D. (1998/1999/2002). The permian period. Informally published manuscript, Biology 1B project for Section 115, University of California Museum of Paleontology, CA, Retrieved from http://www.ucmp.berkely.edu/permian/permian.php
Han, J., Zhang, Z. F., & Liu, J. N. (2008). A preliminary note on the dispersal of the Cambrian Burgess Shale-type faunas. Gondwana Research, (1), 269-276. doi:10.1016/j.gr.2007.09.001
Coral reefs need to be preserved for many reasons. In this paper, I will discuss a few of them. First of all, they house a collection of diverse organisms, and contribute to fisheries which provide food items such as fish, crustaceans, and mollusks. Furthermore, coral skeletons are being used as bone substitutes in reconstructive bone surgery and may be able to provide important medicine, including anti-cancer drugs and a compound that blocks ultra-violet rays, they even help reduce global warming by taking carbon dioxide out of the air. These reefs provide a habitat for many species.