Charlotte Prior
November 2 2014
Earth Science Block C Mrs. McClellan
Citation:
"Low Oxygen 'delayed Life on Earth'" BBC News. N.p., n.d. Web. 02 Nov. 2014. <http://www.bbc.com/news/science-environment-29832046>.
The article I read explains the effect of oxygen levels on earth had on the rate of evolution. These new studies of rocks show that oxygen levels a billion years ago had 0.1% of the oxygen present today. The lack of oxygen prevented the evolution of complex life forms. 800 million years ago the components found in rocks began to change and oxygen became more abundant, the quick rise in oxygen levels led to the Cambrian explosion. This explosion is a sudden increase in the development and evolution of complex life forms, they did not change overnight or every generation, but the change was faster than it has been before. This is only a theory and it has been a question in science for so long, the reason that our animal ancestors took so long to develop lies in the chemical makeup of our atmosphere. This is a new development and some scientists are skeptical but by repeating these tests scientist can conclude more solid results.
This discovery does not affect our lives directly, but it provides an answer to a question that has been debated for a while. The question of how we got here is a difficult one, and the answer is not solid or straight forward. This discovery is just another piece in the puzzle of evolution. A billion years ago only simple life forms existed, modern animals, which led to human evolution had not formed. Scientists wondered why this was the case, and then suddenly 500 million years ago there was a spike in this evolution. By using this new technology scientists can use it to look at these oxygen levels in old rocks and find the reason for this spike. This evidence is a big piece of our puzzle and it means we are one step closer to the answer and full understanding.
This article has very skeptical evidence, whether or not the dating of these rocks and the measuring of the oxygen in them, is valid is a question of the technology. This article was well written and everything made sense. The language in the article was not to complex so that a person would not be able to understand, and the author did a good job explaining the discoveries from the experiment. The author also gives a view of both sides of the argument of the validity of this data, the author is not biased and gives facts not opinions. Overall this article was intriguing and it has a great impact of our knowledge of how we came to be on this planet and with this form.
Charlotte Prior did a fantastic job summarizing and critiquing the article "Low Oxygen 'Delayed Animal Life on Earth."' The question answered here is one I have asked my self a lot, "How did we get here." Thanks to Charlottes write up, i now know that it is thanks to the levels of oxygen increasing over time. I find it interesting that 500 million years ago, there was a spike in oxygen in our atmosphere. I ask myself, why? I am also fascinated that the evidence for this theory is found in the rocks dating back to about 800 millions years ago. Charlotte did a great job summarizing what she read, it was beautifully written and it was a great easy read. I also love how Charlotte admitted that her source may not be trustworthy, and I admire the honesty and willingness to point out a potentially faulty article. I am also skeptical of Charlottes article but because she didn't include any sources or quotes into her review. Besides her lack of credibility, i found that Charlotte provided a beautifully written interesting piece to the blog.
ReplyDeleteI am glad you took an interest on Charlotte's post on how we can tell oxygen spiked on Earth and can see that in the rock record. Though she thought her source was questionable, I can tell you that the evidence is real, and you will see it for yourself firsthand in the American Museum of Natural History tomorrow. Look for the iron rock with red banding and read the sign about that this means in the "Hall of Earth"!
ReplyDeleteCharlotte’s review on "Low Oxygen 'Delayed Animal Life on Earth" was very engaging. To begin, she did a great job summarizing the article. She included actual facts and evidence discovered from the article, which made it easier to understand. I had no idea that a billion years ago the earth had .1% of the oxygen that is present today. In addition, I didn’t know the reason for the increased oxygen levels was the Cambrian Explosion. Lastly, I didn’t know scientists could look at oxygen levels in old rocks and determine how long ago the rocks existed. I was impressed by the amount of evidence for evolution. I also was impressed with how Charlotte gave her personal opinion on the article, which made her review more intriguing. I think Charlotte could have maybe related the article more to present day life, but she did a terrific job!
ReplyDeleteCharlotte's review on this article is better than most reviews. I agree with the other commenters that she did an amazing job both summarizing the article and at wording the review in such a way that it sounded like a student wrote it. I say this because a normal professional review would require a more direct factual analysis and summary, which without a doubt would cause the reader to be lost in a sea of words. By her rephrasing her sentences in such a way that a student would is excellent for this particular assignment because other students would be able to comprehend what is being said, like me. Regardless of the way this review was written, it really informed be about common ideas that I never new about, like a good summary/review should. I not only learned about the theory itself but also a glimpse to what the past was like on our planet (because admittedly, I don't know much about it). By her explaining each in great detail through her review, I was able to learn as much as possible things I had never heard about before. One suggestion that I may suggest that she do in a latter review is that she includes more analysis. Reason? The reason I have is that through her review, I felt as if she was just giving factual information and not relating this personally to every day life. I know that she says that it does not affect us directly in every day life, but it would have been nice for the reader to find some sort of statement, metaphor, or connection to anything in the world that we live in now. Otherwise, I deem this to be a well written review to an amazing topic.
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