Beginning in the 18th century, the concept of paleontology was established and was further developed in the 19th century. Paleontology is the study of prehistoric life, including organisms’ evolution and interactions with each other and the environment around them. It’s also the study of past fossil records of past geological periods and relationships between ancient and modern day species. Although it is a field of biology, it has also been associated with geology because of the attempt to learn about the Earth itself, not just its organisms. This field tries to explain causes rather than observing effects by conducting experiments. The use of paleontology was and still is an extremely important aspect in identifying organisms from the Paleozoic Era, a time period in which extinction and evolution collided with each other, helping to shape the biological world we know today.
The Paleozoic Era began about 542 million years ago and lasted for about 291 million years. It was divided into six parts known as the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. The oldest subdivision of the Paleozoic Era was the Cambrian period, which is also important to paleontologists because the rocks from this time are rich in fossils. During this period, evolution hit its peak, and for about 40 million years animal body plans were rapidly changing (Williams et al, 2007). Because of the sudden explosion of diversity during this period, it is sometimes referred to as the Cambrian radiation or Cambrian explosion. Many of the species that existed during this time period were marine organisms, mainly because at the beginning of the Cambrian period, life was entirely confined to the oceans. The evolution during this time period is...
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...ndred million years, the remnants left behind by them tell paleontologists today a lot about the way they lived and how they adapted. With the understanding and capability to delve deeper into the meaning of a fossil, paleontologists can now attempt to unravel the unknown from past time periods. The ability to examine a fossil using calcite remains and DNA has improved throughout history due to our advances in technology and the knowledge gained from past discoveries. Conclusions can finally be drawn and proved about the existence of trilobites. What we know today about trilobites is published throughout the world, revealing their lifestyles, eating and reproduction patterns, relatives to this species, and how they managed to adapt to the environment around them. The mystery of the trilobite has finally filled a missing chapter in the novel to the Earth’s history.
In the year 2002 a bizarre looking theropod dinosaur fossil was found in China (Xu). It challenges the way researchers have been thinking of theropods and other dinosaurs for a long time. In the Sahara desert, the oldest hominid skull in the world was found that same year. These are just two of many discoveries that have challenged the way we perceive the ancient world.
In the early 1800’s, a new discovery that left paleontologists in awe was the fossil finding of the immeasurable amount of species of reptiles, Ichthyosaurs. Greek for “fish lizards”, these fossils were found all over the world. Because these large aquatic reptiles migrated just as whales do today, paleontologists have had the amazing advantage of collecting fascinating bone fragments throughout the past 177 years. Ichthyosaurs swam the ocean life from about 245 million until about 90 million years ago- approximately the same time dinosaurs ruled the land. The earliest Ichthyosaur fossil findings were in parts of Canada, China, Japan, and possibly Thailand. Countless fossils came from coatings of limestone produced out of the ocean-floor ooze that was predominantly superior at preserving very well facts of the creatures it digested (Perkins 2).
The Permian-Triassic Extinction is a mass extinction that occurred between the Permian and Triassic geologic time periods approximately 250 million years ago; it is the deadliest of all extinctions that have occurred on Earth. In addition, during the Permian-Triassic extinction the continents of today existed as one supercontinent known as Pangaea. This was the first time in history where continental or land mass exceeded that of the ocean. This was also before dinosaurs of the Triassic period roamed Earth, during this time animals such as the therapsids, and Synapsids such as the Pelycosaurs, insects and amphibians also occupied Earth. Fauna that existed during the Permian period includes Gymnosperms, or seed producing plants such as the Conifers. Other animals that existed during this time include marine life such as brachiopods (clams), bryozoans (coral-like skeletons), bony fish and sharks, as well as crinoids (sea urchin like creatures). According to National Geographic, about 90 percent of all the animals and fauna of this period perished, the marine life was hit the hardest wi...
The team of scientists consisted of a biogeologist, geochemist, and tectonic geologist with the common goal of understanding the coevolution of life and environ...
Geologic development contributed to the Cambrian explosion. There was a supercontinent called Rodina that broke up to make continents. There was an ice age but the Earth continued to warm creating new life forms. There things called invertebrates that had no backbone. Life forms also had a hard outer shell to protect them. The trilobite is an arthropod that had a hard outer shell. In only 15 million years many different types of organisms evolved. Cambrian reefs made up of sponges flourished.
The Cambrian time period was the first in the Paleozoic era. It lasted about fifty-three million years. As the period started, the continents started to pull apart. Land masses were scattered. During this time period the oceans started to oxygenate. The Cambrian was thought to be in the middle of two ice ages; however, there were no significant ice formations during this tim...
Zhou, Z., Barrett, P., & Hilton, J. "An exceptionally preserved Lower Cretaceous ecosystem." 421. 20 February 2003: 807-814. 4 April 2004 <www.nature.com/nature>.
A whole lot of hypotheses have been used to explain the quick expansion of animal species in the early Cambrian period about from about 541.0 million to about 485.4 million years ago. The most modern explanations for the Cambrian explosion takes pieces of a lot of these hypotheses and melds them together; incorporating genetic, ecologic, abiotic conditions that set the evolutionary wheel in motion. The current state of understanding the Cambrian explosion still remains a topic of open and exciting debate. The processes in the hypotheses can be stand-alone or very tightly interconnected and mutually supporting of another. One can say the complexity of modern Animalia can be attributed to the complexity of the processes that happened during the rapid diversification attributed from an interaction of biotic and abiotic processes in the Cambrian period.
Trilobites are extinct sea creatures that were one of the first forms of life on earth.
...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
Majungatholus atopus roamed the plains of northwestern Madagascar about 70 million years ago during the Late Cretaceous (Perkins, 2003; Rogers et al, 2003). The discovery of 21 tooth-marked elements originating from two Majungatholus atopus individuals suggests evidence that the dinosaur supplemented its diet by feeding on its own dead or hunting them (Rogers et al, 2003). It cannot be confirmed whether they were purely scavengers, hunters, or both. Scientists are certain that the marks are not the doing of any other predator because the teeth marks are not consistent with any other known species that lived in the area. Only one other theropod that inhabited the area during the time Majungatholus atopus did, Masiakasaurus knopfleri, had teeth and bite marks too small to have caused these markings. Two large crocodile species also shared the same ecosystem but their teeth were “too blunt and too irregularly spaced to have produced the narrow grooves found on the Majungatholus bones”(Perkins, 2003). The tooth marks on at least nine Majungatholus elements attest to intertooth spacing in the perpetrators jaw and denticle drag patterns consistent enough to make a compelling case for Majungatholus feeding on other Majungatholus (Rogers et al, 2003).
There are several theories about how the Cambrian Explosion started. There were major changes in marine environments and chemistry from the late Precambrian into the Cambrian, and these also may have impacted the rise of mineralized skeletons among previously soft-bodied organisms. One theory as to what happened is that oxygen in the atmosphere, with the contribution of photosy...
With its abundance of genera, the Burgess Shale is one of the world’s most important fossil fields. It’s discovery in 1909 led to over 100 years of paleontological study in the Canadian Rockies, a majority of which has been carried out in two quarries known as the Walcott and Raymond quarries (Hagadorn, 2002). Though he was originally in search of trilobites in the Burgess Shale Formation, paleontologist Charles Walcott also discovered a diverse group of soft- and hard-bodied fossils, from algae and sponges to chordates and cirripeds (Hagadorn, 2002). Soft-bodied fossils are incredibly rare due to their delicate structure and susceptibility to decay, so it is hard-bodied fossils that more regularly occur in fossil findings. However over 75,000 soft-bodied specimens have been found in the Burgess Shale formation (Hagadorn, 2002). These specimens are preserved in layers of shale formed from deposits of fine mud. One of the most significant species discovered is the Pikaia gracilens. Believed to be an early chordate, the Pikaia gracilens existed very close to the beginning of the evolutionary path that ultimately lead to humans (McGraw-Hill Encyclopedia, 2006).
The Jurassic period is known as one of the most interesting periods of time in earth’s history, mainly for the awe-inspiring creatures many of which have gone extinct, the most remarkable being the dinosaurs. Life in the ocean during this time was also extremely diversified and amazing for the creatures it beheld. The Jurassic occurred from 199.6 to 145.5 million years ago, following the Triassic Period and preceding the Cretaceous Period within the Mesozoic Era. The supercontinent of Pangea began to drift apart during this time. Right before the Jurassic period began, a major extinction event occurred wiping out much of the life on earth. The events that unfolded afterwards gave life to a new planet.
Many kinds of cumulative change through time have been described by the term "evolution," and the term is used in astronomy, geology, biology, anthropology, and other sciences. This document focuses o...