Tuesday, February 25, 2014

My molecular evolution midterm test

My students wrote the midterm test today. Here are the questions. They had to answer the first question and 4 other questions (out of 5). How would you do?

  1. What’s the most important new thing about molecular evolution that you have learned in this course so far? Explain your answer by describing your "important new thing."
  2. If mutation rates are relatively constant then why does the molecular clock tick at different rates in different proteins?
  3. Many evolutionary biologists think that population genetics is the key concept in understanding evolution but biology students often complete several years of courses without ever learning about effective population sizes, mutation rates and the importance of random genetic drift. Why? Is it because population genetics is not a necessary key concept in evolution?
  4. Grad students at this university publish a journal called Hypothesis. A few years ago (2005) there was a student who wrote ...
    I am a grad student, and long hours at the bench have got me thinking of other things lately, including the idea of marriage. I came up with a few criteria to direct me on my quest for a wife, and near the top of the list was that she needs to know what a gene is. I thought that this would be a reasonable thing to ask for. I like learning about how we and the rest of life work, and knowing how, in a general sense, cells are programmed to do what they do is a pretty good indicator of similar interest. My friends, however, disagreed with me, and on several occasions, as I shared my list, I feared that things were going to get violent. They argued that I will never get married with such a short-sighted and elitist attitude.
    Imagine that you would only seek partners who knew what a gene was. What definition would you require and why?
  5. What’s the best evidence that a substantial amount of our genome is junk?
  6. Imagine that you are teaching a class and you ask students to calculate a mutation rate in humans based on what they know about biochemistry. What mistakes are they most likely to make and why?