Thursday, January 28, 2010

SNOW DAY!! Both 9:00 and 10:00 Sections CANCELLED on FRIDAY


As I am sure you are all aware by now, Tech is closing down at 12:30 on Thursday afternoon and will not reopen until 10 AM tomorrow. Thus, the 9:00 section of BIOL 1404 is cancelled by university policy. In order to keep the whole class on the same lecture schedule, we have decided to cancell the 10:00 section on Friday as well.

I know that this is a terrible blow to most of you because you were so excited about learning about population ecology graphs tomorrow (because "dog gonnit, you love graphs"). Sadly, this will have to wait until Monday.

Stay Warm, Dry, and SAFE- I'll see you on Monday.

Wednesday, January 27, 2010

Homework #2- Due February 1st

The second online homework (Behavior) assigment is due by 11:59 PM on Monday February 1st.

Monday, January 25, 2010

SI and Group Office Hours


SI (Supplemental Instruction) and Group Office Hours offer chances for students to meet regularly to ask questions about BIOL 1404.

SI

SI Leader: Brittany Embry (undergrad and former 1404 student)

Meeting Times and Place

Tuesday 7:30-9:00 Holden Hall 150

Thursday 5:30-7:00 Holden Hall 150

Group Office Hours

Group OH Leader: Dr. McGinley

Meeting Time and Place: Mondays 5:30 in room 21 in Biology Building

Sexual Selection



I think that sexual selection is one of the most interesting topics in all of biology. First, studyign this topic helps to illustrate that natural selection is much more than "survival of the fittest". Second, many of the traits produced by sexual selection are particularly bizzare. Finally, I think that it is fun to use what we have learned about mate choice in animals to helping us to understand human behavior.


Expected Learning Outcomes


By the end of this course a fully engaged student should be able to


- discuss the critical difference between males and females and discuss how this difference influences differences in behavior and morphology between species.

- discuss why sexual selection is just a subset of natural selection

- discus why females should be choosier about who they mate with than males

- discuss why males often compete with other males to fertilize eggs of females

- compare and contrast male-male competition in species with internal fertilization and species with external fertilization

- describe the studies used by scientists to see if females are capable of choosing the best males

- discuss how females can determine which is the best male

- discuss why the variation in female reproductive success is much less than the variation in male reproductive success

- discuss how you would use sexual selection to help you understand human behavior


Past Exam Questions (answers at the bottom of the post)


1. Why are females choosier than males about who they mate with?
(a) female gametes are much more expensive than male gametes
(b) male gametes are much more expensive than female gametes
(c) in some species, males are larger than females
(d) in some species, males compete to mate with the female
(e) c and d


2. Why should females prefer to mate with the oldest males?
(a) because they can pass on good mating genes to their daughters
(b) because they can pass on good survival genes to their sons
(c) because the can pass on good survival genes to their daughters
(d) a and c
(e) b and c


3. Why might females sometimes cause male-male competition to occur?
(a) to assure that she mates with the oldest male
(b) to assure that she mates with the most symmetric male
(c) the male who wins the fight is likely to have “good genes”
(d) a and c
(e) a, b, and c


Further Reading


Here is a link to a website that a student sent to me last year called "The 30 Strangest Animal Mating Habits" http://www.neatorama.com/2007/04/30/30-strangest-animal-mating-habits/

Take a look at this and see if you can relate what the animals are doing to some of the theories that we have talked about in class.


Here is a link to a youtube video showing the mating display of lyrebirds. I was lucky enough to see a lyrebird doing its mating display when I was a kid living in Australia. There was a professional nature photographer who had been hiking around the bush for a couple of weeks waiting to see the display and he was pissed that my Dad and I were able to see the display after spending only about an hour in the woods. What do you think is going on with the lyrebirds?





Here is a link to the Powerpoint Presentation I prepared for this topic.

http://www.slideshare.net/secret/CG2HHvtrLA1KwL

Answers. 1. a, 2. e, 3. c

Friday, January 22, 2010

Antibiotic Resistance



I think that the evolution of antibiotic resistance is an interesting and important issue. Below I has listed the expected learning outcomes for this topic in BIOL 1404. Because this topic has widespread medical relevance I have included a lot of additional readings and a powerpoint presentation that I developed for another class last semester. This info is not required, but is only intended to provide more info to interested students.

Expected Learning Outcomes

By the end of the course a fully engaged students should be able to

- discuss the causes of the development of antibiotic resistance

- discuss where antibiotics come from

- discuss what we have learned from ecology and evolutionary biology about potentila problems associated with antibiotic use

- discuss what we have learned from evolutionary biology that should help us fight microbial diseases more effectively

Past Exam Questions (answers at the bottom of the post)

In the 1950s, Japanese physicians began to notice that some hospital patients suffering from bacterial dysentery, which produces severe diarrhea, did not respond to antibiotics that had generally been effective in the past.

1. In order for the result described above to have occurred, which of the following must have been true in the population of dysentery-causing bacteria?
(a) there was variation in the susceptibility of the bacteria to antibiotics
(b) antibiotic resistance was heritable
(c) bacteria that were more resistant to antibiotics had higher survival rates than less resistant bacteria
(d) a, b, and c
(e) neither a, b, or c was true


2. What can be done in future to limit the problem of antibiotic resistance in disease-causing microorganisms?
(a) Doctors should only describe antibiotics when appropriate
(b) Doctors should prescribe larger doses of antibiotics
(c) patients should make sure to take all of the pills when antibiotics are prescribed
(d) a and c
(d) a, b, and c

Answers 1. d 2. d

Further Reading

Evolution of Antibiotic Resistance-
http://www.pbs.org/wgbh/evolution/library/10/4/l_104_03.html

Antibiotic resistance: Questions and Answers- CDC
http://www.cdc.gov/getsmart/antibiotic-use/anitbiotic-resistance-faqs.html

Antibiotic resistance- delaying the inevitable (parts 1 and 2) UC Berkeley
http://evolution.berkeley.edu/evosite/relevance/IA1antibiotics2.shtml

HIV the ultimate evolver (parts 1-3) UC Berkeley
http://evolution.berkeley.edu/evosite/relevance/IA2HIV.shtml

Resisting our drugs-
http://understandingevolution.com/evolibrary/article/0_0_0/bergstrom_03

Turbochared evolution-
http://understandingevolution.com/evolibrary/article/side_0_0/turboevolution_01

Relevance of evolution:medicine-
http://understandingevolution.com/evolibrary/article/0_0_0/medicine_01

Powerpoint Presentation

Here is a link the the powerpoint presentation I used in that class.

http://www.slideshare.net/secret/rPekyBdLalUvFY

Thursday, January 21, 2010

Cultural Selection

In humans there are examples of alturistic behaviors that appear to be difficult to explain by kin selection of reciprocal altruism (e.g. soldiers sacrificing their lives in battle, police or firefighters risking their lives, catholic priests remaining celibate).

Genes are self replicating molecules. Genes produce our bodies which in turn produce more copies of their genes. Richard Dawkins has suggested that we think about genes as being "replicators" and our bodies as being "vehicles" whose job it is to make more copies of the replicators. If we can not explain altruistic behaviors as strategy for increasing the transmission of genes into the next generation them maybe we need to search for another kind of "replicator". Dawkins has suggested that "ideas" (he calls them "memes") are also capable of self replication. Because ideas differ in how long they survive and how well they are passed on it should be possible to have selection for ideas (cultural selection).

Expected Learning Outcomes

By the end of this course a fully engaged student should be able to

- identify examples of altruistic behavior that might be explained by cultural selection
- be able to compare and contrast "natural selection" with "cultural selection"

Further Readings

Cultural evolution http://plato.stanford.edu/entries/evolution-cultural/

One of my favorite books of all time is "The Selfish Gene" by Richard Dawkings. He discusses some of his ideas about cultural selection in the final chapter of this book. Here is a link to that chapter in case you are interested
http://www.rubinghscience.org/memetics/dawkinsmemes.html

I think this chapter is a must read for any educated person, I hope you enjoy.

Reciprocal Altruism and Evolutionary Psychology


Drawing of a hungry vampire bat (right) solicits food from a potential donor, first by grooming around the stomach area (c) and then licking the donor's face (d). The donor bat then responds by regurgitating blood (e) if receptive. (Wilkinson 1990)

Altruistic acts among non relatives can be understood by reciprocal altruism. As we discussed in class we would expect reciprocal altruism to be limited to species that show long term associations and are "smart" emough to be able to recognize individuals and remember who owes them and who does not.

Examples of Past Test Questions (answers at the bottom of this post)

1. It is not uncommon for college students to share items such as shampoo with their roommates. Which of the following hypothesis best explains this behavior?
(a) group selection
(b) kin selection
(c) reciprocal altruism
(d) selfish behavior
(e) altruistic behavior

2. Which of the following terms apply to a roommate who borrows your shampoo when she/he has run out, but will not allow you to borrow their shampoo when you need it?
(a) altruistic
(b) mutualist
(c) cheater
(d) a and c
(e) b and c



Further Readings

Reciprocal Altruism http://www.bbc.co.uk/nature/animals/mammals/explore/altruism.shtml

Reciprocal Altruism in Vampire Bats http://www.bio.davidson.edu/people/vecase/behavior/Spring2002/Perry/altruism.html

If you are interested in learning more about Evolutionary Psychology here is a link to a bunch of Frequently asked questions. Some of this goes into way more detail than we need to be worried about for this class.
FAQ Evolutionary Psychology http://www.anth.ucsb.edu/projects/human/evpsychfaq.html

Expected Learning Outcomes

By the end of this course a fully engaged student should be able to

- define reciprocal altruism
- discuss the conditions under which altruistic acts can be explained by reciprocal altruism
- examine an example of an altruistic behavior and determine whether reciprocal altruism is the best explanation
- explain how participants benefit by being involved in reciprodal altruism in real world examples (e.g, vampire bats)
- define a cheater in a reciprocal altruism system and discuss (a) why cheating is a problem in the system and (b) what organisms can do to reduce cheating
- discuss Trivers' ideas about how human psychology has been influenced by reciprocal altruism (be able to provide your opinion about Trivers' ideas and be able to back up your opinions)


Answers 1. c even though this is an example of altruistic behavior, the best explanation for this behavior is reciprocal altruism) 2. c