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| Second Edition Published by Dover Publications |
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Fossil or Not?
Identifying fossils is a more complicated task then you'd think. There are lots of different kinds of rocks, which can have their own unique patterns in them. Some of these patterns are the remains of ancient life; others are abiotic structures, chances of mineralization or later erosion that lead to pseudofossils...
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Why Pluto Should Not be a Planet
It was 2006 when the International Astronomical Union declared that Pluto was no longer going to be considered a planet. Ironically, this was probably one of the best followed scientific controversies of my lifetime...
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Dinosaurs: Now in Color
A few months back, I talked about how scientists had found evidence of iridescence in fossil feathers. At the time, that was a huge step forward. We still didn't know what colors dinosaurs were, but we could find out something from microscopic structures in well-preserved feathers. Now, we've got something even cooler...
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Life on Mars
The question of how much life there is in the universe is one of the most fundamental questions in astronomy, and possibly all of science. While we are just now on the brink of finding Earth-like planets around other stars, the possibility of life existing on planets very different from our own still remains...
January 25, 2012
Book Review: Fads & Fallacies in the Name of Science
January 20, 2012
Getting Students Invested
I have seen teachers use contracts in the classroom before, but not like this. The basic idea is you show students the requirements for each letter grade at the start of the semester. Each assignment is pass fail and can be repeated a fixed number of times. So for example to get an A you needed to get above 80% on 4 exams, do 3 of 4 written assignments, and 3 of 4 activities. To get a B in the class you would need to get above 80% on 4 exams, do 2 of the 4 written assignments, and 3 of the 4 activities. The student gets complete control over what activities and written assignments to do but for whatever assignments they chose they need to show a very strong understanding of the material. The idea is to get students to set their own goal at the start of the semester and then focus on mastering the material throughout the semester, not just remembering a percentage of it.
I really like this idea for several reasons. Giving students more control makes them more responsible for their own learning. That alone can be really motivating for many students. I also like the idea of letting students retry assignments because it makes them look at their previous work critically and look for ways to improve on it. Lastly, I think it is really good for students to learn to set goals early with a clear idea of what they will need to do to achieve that goal.
As nice as it is that this kind of student contract caters to my philosophical notions about how we should teach students, the real question is, does it work? The answer appears to be a tentative yes. To test it researchers at Western Illinois University compared two freshman psychology classes. The teacher and content was the same in both courses but one is a traditional grading system and the other used this contract grading system. To quote the press release...
...at the end of the semester, the group of students who were graded contractually were three times more likely to earn an A grade, one third as likely to fail or withdraw from the course, perceived a higher degree of control over their grade, and consistently rated their own effort, their instructor, and the course overall more favorably.It is important to note that is was a small study and it was done on the college level so it is hard to say how well it would apply to a K-12 environment. We also can't rule out effects like the teacher being biased towards the contract grading system or the result being a statistical fluke. Still I think it is a really interesting idea. One that deserves more studies at more educational levels.
The full paper is titled "Use of Contract Grading to Improve Grades Among College Freshmen in Introductory Psychology" by Dana F. Lindemann and Colin R. Harbke and can be found at http://sgo.sagepub.com/content/early/2011/12/22/2158244011434103
January 18, 2012
Dynamic Earth: Happy Birthday, Baby Island!
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| From Universe Today |
January 17, 2012
Scientific Unknowns: What is Life Redux
| Image Credit: JFantasy via Wikimedia Commons |
This all started when Edward Trifonov, a biologist at the University of Haifa Isreal, proposed a three word definition of life. To quote from the article by Carl Zimmer on Txchnologist...
Trifanov analyzed the linguistic structure of 150 definitions of life, grouping similar words into categories. He found that he could sum up what they all have in common in three words. Life, Trifonov declares, is simply self-reproduction with variations.In his article, Zimmer does acknowledge that there is a considerable amount of criticism but he mostly focuses on what this definition might be missing, metabolism, information and so on. I was interested, though, when I read a critical piece by Sean Carroll asking if reproduction should even be a part of our definition. He says...
...the idea of reproduction looms large in many people’s definitions of life. But I don’t think it really belongs. If you built an organism from scratch, that was as complicated and organic and lifelike as any living thing currently walking this Earth, except that it had no reproductive capacity, it would be silly to exclude it from “life” just because it was non-reproducing. Even worse, I realized that I myself wouldn’t even qualify as alive under Trifonov’s definition, since I don’t have kids and don’t plan on having any.
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| 3 Legged dog on the right Photo Credit: Jon Hurd via Wikimedia Commons |
So what is life? I certainly don't have an answer. Right now we have a sample size of one*. Until we find life somewhere else in the universe, I wouldn't expect any real agreement on this deceptively simple question.
*After all, every living thing we have found on the Earth shares a common ancestor.
January 15, 2012
Pardon Our Construction
Thanks!








