Introduction
According to scientists, one of the most extraordinary bursts of evolution ever known was the Cambrian Explosion. For most of the nearly 4 billion years that life has existed on Earth, evolution produced little beyond bacteria, plankton, and multi-celled algae. Then, about between 570 and 530 million years ago, another burst of diversification occurred. This stunning period is termed the "Cambrian explosion," taking the name of the geological age in which the earlier part occurred. A recent study revealed that life evolved during the Cambrian Period at a rate about five times faster than today. But it was certainly not as rapid as an explosion; the changes seems to have taken around 30 million years, and some stages took 5 to 10 million years. The Cambrian explosion was a period of time where life evolved into numerous multifaceted organisms that developed into the vertebrates and human life as we know today.
The Cambrian Explosion took place in the Paleozoic era where a diversity of life emerged, leading to the lineages of almost all animals living today. Included in this group are chordates, a group of vertebrates, which humans are a part of. Ever since this phenomenon, numerous species have evolved with great changes including Homo sapiens. What happened during the Cambrian Explosion and how did it impact human evolution?
Common Theories
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...
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...o happen. But with the help of fossil evidence we are able to identify common ancestors and evolutionary pathways between species. We also identify oxygen as a major key contribution for life to evolve. Also, through scientific research it has been established that arthropods and chordates have shared genes, leading to the path of vertebrates and human life.
Works Cited
http://www.pbs.org/wgbh/evolution/library/03/4/l_034_02.html
http://biologos.org/questions/cambrian-explosion
http://www.darwinsdilemma.org/pdf/faq.pdf
http://science.nationalgeographic.com/science/prehistoric-world/cambrian/
http://books.google.com/books?id=nAh7AgAAQBAJ&pg=PA9&lpg=PA9&dq=cambrian+explosion+human+evolution&source=bl&ots=j--hqsl0WE&sig=q2yEIfk6KKJ-bO2tLKXl2k93z_8&hl=en&sa=X&ei=6px2U82iLY2YqAaf3oGICA&ved=0CJMBEOgBMA8#v=onepage&q=cambrian%20explosion%20human%20evolution&f=false
Issac Leib Peretz once said, “Time is change, transformation, evolution. Time is eternal sprouting, blossoming, the eternal tomorrow.” In PBS’s Documentary Great Transformations, the transformation from the first living organism to what we are today was discussed and how most organisms have very similar genes and characteristics. How fish used to colonize land and land mammals evolved to sea creatures.
As time progressed, Ichthyosaurs transitioned their body like features from a lizard-shaped body plan to a fish-shaped one through the early and middle Triassic periods. In 1927, the first bone fragments were foun...
[1] This problem with the theory of evolution was addressed by Stephen Jay Gould and other evolutionists. They postulated the punctuated equilibrium theory of evolution, which does not predict the numerous fossils predicted by the orthodox theory of evolution.
As the decades pass, technological advances have enabled researchers, entrepenures and pondering minds the ability to discover more and more about every aspect of our very existence. Over the past three decades the evolutionary tree of life has been expanded at least seven times over. Major advances have been made in the area of evolution to open the eyes of many to the extensive history of the earth. For the very first time, we have tangible knowledge that life evolved and grew to become a flourishing success during the young ages of the Earth. By 3.5 million years ago life was already well advanced. Before this breakthrough no one could have thought that life occurred so amazingly early, that Earth was inhabited by a huge array of tiny life forms through t the first four-fifths of it’s existence, and no one deduced that evolution itself evolved over geologic time.
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...
"Evolution and the Fossil Record by John Pojeta, Jr. and Dale A. Springer." Evolution and the Fossil Record by John Pojeta, Jr. and Dale A. Springer. N.p., n.d. Web. 15 May 2014.
The Cambrian explosion refers to the speedy diversification of new forms of animals arising within the fossil record in the span of about 20 million years. This may not seem to be the shortest time frame, but in an evolutionary sense it was lightning fast. Some of the early fossils are unusually intact and very well preserved. Two of the more famous locations of Cambrian fossil discoveries are the Burgess Shale discovered by Charles Walcott on August 30, 1909 in Canada and the Maotianshan Shales in Chengijang, china.
They ruled the world before the time of the dinosaurs, from the Cambrian Period to the
happen? If not, then why should science teachers teach that life evolved over billions of
According to the theory of evolution, approximately 3.8 billion years ago some chemicals accidentally structured themselves into a self-replicating molecule. This beginning spark of life was the ancestor of every living thing we see today. Through the processes of mutation and natural selection, that simplest life form, has been shaped into every living species.
The theory of evolution is quite sophisticated scientific theory that has received a lot of misinterpretation and distortion. However, it can be explained very simply by integrating several important concepts into one definition. Coyne (2009, p. 3) sums up the entire theory in one sentence, “Life on Earth evolved gradually beginning with one primitive species—perhaps a selfreplicating molecule—that lived more than 3.5 billion years ago; it then branched out over time, throwing off many new and diverse species; and the mechanism for most (but not all) of evolutionary change is natural...
The time between the formation of the earth and the beginning of the Cambrian(about 570mya) is a 4000 my long period known as the Precambrian, this includes approximately 90% of geological time of which we know very little about as pre-Cambrian rocks are poorly exposed, many have been eroded or metamorphosed and fossils are seldom found.
The theory of evolution, as set forth by Charles Darwin in 1859, stated that all plant and animal life evolved over long periods of time from simple to more complicated forms through mutation and adaptation. He also taught that only the fittest of each species would survive. He further postulated that the first living cell evolved in a "warm warm little pond" and that it took billions of years for the present diversity of living things to evolve. At the time, it was thought that the few "missing links" in the fossil record would be soon filled.(Darwin, 1927 ). Today, however, there is today a considerable body of scientific evidence that refutes this entire theory.
Over the past century, the Burgess Shale has revealed important information about the development of earth’s history. The excavation of the Burgess Shale formation provided evidence for what was once just a theory in evolution. The taphonomic findings of the Burgess Shale have played a significant role in understanding the large diversity that resulted from the Cambrian explosion, advancing the study of evolutionary assemblages for Paleontologists worldwide.
Francis Crick, co-discoverer of DNA, has said that “the origin of life appears to be almost a miracle, so many are the conditions which would have to be satisfied to get it going” (Horgan 27).2 Noted evolutionary astronomer Frederick Hoyle has described the chances of life having evolved from nonlife to be about as likely as the chances that “a tornado sweeping through a junkyard might assemble a Boeing 747 from the materials therein” (Johnson 106). Why do respected scientists doubt what textbooks teach as fact? It would appear that these scientists know something that current theories describing the origin of life fail to explain. While current theories describe scenarios in which genetic material such as RNA becomes entrapped in a protective cell membrane as a likely recipe for the formation of life, they generally do not focus on the difficulties of forming and concentrating all of these components in the first place.3 To clarify, current theories suffer from what I call the “cookbook mentality.