Saturday, November 22, 2008

An end to Eco Lab :-(

Earlier last week, we conducted our final Ecology Lab experiment. The purpose of the experiment was to observe characteristics of Island Biogeography. We used ping-pong balls to represent our colonizing species and empty egg cartons to simulate the islands to be colonized. First, we used a empty egg carton which was capable of holding one dozen eggs or ping-pong balls, then we used one half of a carton, capable of holding, duh, six ping-pong balls. Using five balls for each trial, Krizia stood about 1 meter from the 'large island' and tried her best to 'colonize' or bounce, each ball into one of the cups of carton. Liz and I counted how many instances of colonization she got for each trial and caught balls as they flew every which way. After each trial of five balls being tossed at the island we rolled a die to determine at which cup within the carton there would be an 'extinction' event (all cups of the carton were previously labled). By extinction event I mean that if we rolled the die and say rolled a two and there was a ping-pong ball in cup two, that ball would be removed and not counted in the final number of colonizations. We then repeated the procedure after having moved the same carton two meters away from Krizia. Then we used the 'smaller island' to carry out the same procedure while Lisa recorded all of the data and made calculations. What we determined from our readings and experiments was that with a larger sized island, there is decreased chance of extinction. With the smaller island there is increased chance of extinction. Also, as the distance from the 'mainland' increases, there are decreased immigration rates.

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