Research and Finish Setup!

From last week’s assignment to look for a reliable published reading, I came across pill bug's “male effect”. The “male-effect” is characterized by a significant shortening period of the pre-parturial intermoult (PPI) during which oocyte maturation spontaneously takes place. The prolonged presence of male along with females is known to boost female reproductive physiology. From the paper, the study resulted in the ideas that the “continuous presence of a male can speed up vitellogenesis and the moulting cycle, so to reduce female PPI by 15-20 day” (177). Results also indicate that the earlier and longer the copulations, the stronger the “male effect” can be. From the published data, a conclusion of “females are adjusting their reproductive physiology according to the presence/absence and the intensity of male mating stimuli” (177) was proven. During this meeting, Mr. Calos ordered pill bugs. I also prepared two tanks (for the convenience after sorting out males and females) in preparation for the bugs to arrive on Friday.


For the full text of the published research article, please visit:

http://www.tandfonline.com/doi/abs/10.1080/07924259.2010.9652331

FRANÇOIS LEFEBVRE & YVES CAUBET (2010): Female-extended control over their reproductive investment: the role of early mating interactions on oocyte maturation in the terrestrial crustacean Armadillidium vulgare (Latreille, 1804), Invertebrate Reproduction & Development, 54:4, 177-186.

Project Begins!

This week, I am actually starting the project - Mr. Calos and I set up my experiment station downstairs of Weaver. I then started researching about the determination of gender for pill bugs. I interestingly found out that male pill bug has a pair of long blade-like appendages near its hind legs while female does not. The way to know that is to hold the bug gently and turn it upside down to check. Here is the link as to where I got the information: http://snailstales.blogspot.com/2008/02/is-it-boy-or-girl.html. I then moved on to observe some of the pill bugs; I was not able to get one by just using my hands, so I will have to use some forceps to help me. Before my next meeting, I will have to look for some published books that discuss about pill bug’s sexual behaviors, and learn more.

Here is a picture of what a male pill bug will look like:

Settling on a Topic!

For this meeting, I brought in websites that I found on insects’ (not pill bug specifically) sexual behaviors and learned more about the expression of such behaviors. For pills bugs, I could not specifically find anything on their sexual behavior but when I was researching about pill bugs via the Internet, I read a lot on the environment they usually live in, their reproductive cycles, the terrestrial behaviors, etc. However, I am really interested in finding out about the sexual behaviors of them so Mr. Calos and I decided that we should investigate more on their reproductive behaviors. So for the meeting after winter break, I am going to read books on pill bugs and try to discover any special activity they have when they start their reproductive cycle.

Closer to a Start!

In my reading, I came across the marine isopod Paracerceis sculpta, a species with more than one coexisting reproductive strategy. The males of this species differ in sizes: large (alpha), medium (beta) and small (gemma), and each of these have its own behavioral phenotype (Alcock, pg338). There are different kinds of male reproductive success for these three types of males, and that fact interests me. However, it is difficult to find a species that exhibits a distinct behavior in the reproduction process (e.g. male-male competition). Even though the sponge isopod would be an ideal organism, it will be challenging to set up for its experiment, hence why another organism that fits the criteria should be use. Insects first came to my mind as the isopod vaguely resembles sowbugs or pillpugs. For the next meeting, I am to research about pill bugs, their reproductive behaviors (if any) and how they reproduce.

Time to get going!

After reading more about male dominance and reproductive success, I came to the meeting by raising basic internship-related questions. Mr. Calos and I discussed a lot about quantifying reproductive benefits as well as how to track them in a population. We also looked into the example of Drosophila. Drosophila is the scientific name for fruit flies, and the book has specially mentioned this organism to have a unique evolution of gametes. Fruit flies is a species in which males produce oversized sperm that are (when uncoiled) ten times longer than their bodies – the mass of an egg, though, is still vastly greater than the size of a sperm (Alcock, pg322). Sex and gender behaviors were also discussed. In general, we plan to come up with an idea to determine the hypothesis and the experiment itself before Revels. For the next meeting, I will continue reading Alcock’s book and brainstorm about some experiments.

Knowing More About Behaviors!

For this week, I chose to read about Behavioral Adaptations for Survival, Choosing Where to Live, the Evolution of Reproductive Behavior and the Evolution of Mating System. The reading was just a skim-through to understand more about what kinds of animal behaviors I am interested in. At the meeting, I discussed about some fascinating factual statements about dominance hierarchy (in which individuals that live together in groups interact aggressively for a while before sorting themselves out from top dog to bottom mutt; the alpha male will signal submissiveness to the lower-ranking male; from Alcock pg332).  We also talked about what kind of approach I would want for my internship, whether it will be topic/question-orientated or it will be an organism-based project. The conclusion was that I keep my options open while thinking about what my experiment will be like:  using natural organisms that I can find around the area or lab organisms. For the next meeting, I will read more about male reproductive success and dominance.

Getting Started!

For the first meeting, I discussed with Mr. Calos about my science internship interests. Before this meeting, I have thought of doing a PCR lab but I backed up and brainstormed more directions for my internship. At the meeting, Mr. Calos and I discussed about possible ideas to do and I mentioned I want to do something that allows me to learn and gain a deeper understanding of what I have learned in class before. I have a high interest in cell biology (about diseases, cell abnormality or genetic problems) as well as medical-related sciences (e.g. cancer tumors). Anatomy and physiology was something that came to mind; and that would involved dissections (something I enjoy a lot). On top of those, I also expressed interest in animal behaviors.  This direction is broad as I am curious to learn different kinds of behaviors such as make decisions of territory, food, inter-organism exchange. For the next meeting, I will research more ideas and read a book on Animal Behavior.