· Food Chain Menu

Ecosystem

You can watch an ecosystem in action, observing how the three populations interact—grass, mice, and fox—with each other and change as time passes. You have many online graphing options to watch the data unfold and see the trends. You can just watch and observe to get a good feeling about the process. Or you can take notes and formulate hypotheses, and test these hypotheses on other trials. You can download the data to do an analysis for your own spreadsheet. In Dave Volek's Food Chain, you choose how you interact with the data coming from the ecosystem simulation.

The computer program will generate the starting numbers for each ecosystem simulation. In this way, no simulation will behave exactly like any other simulation. However, you should start seeing some similar trends after going through several simulations. The challenge is to predict how the grass, mouse, and fox populations will change from month-to-month and when population reversals are going to happen.

The Ecosystem differs from the Laboratory in three important ways. First the area is expanded to 10km x 10km. Second, foxes are added to the Ecosystem. So you can now observe how the foxes interact with the grass and mice.

A third difference is that, in the Laboratory, you were provided with all sorts of information about mouse pups because the mouse dens were electronically monitored. In the Ecosystem, mice are making their own dens so there is no electronic surveillance. Because the dens are underground, beyond the visual reach of the observers and any population sampling techniques, you will get no information about the mouse pup population (but you still get reliable data for mouse juveniles, adults, and elders). Hopefully you have learned something about mouse pups from the Laboratory to help you understand the mouse trends you are seeing in the Ecosystem.

The Food Chain computer program will continue to use exactly the same mouse algorithms in the Ecosystem as it did in Laboratory. The only exception is mouse death by predation. Many mice will find their way into the stomachs of foxes, something that did not happen in the Laboratory. But other mortality rates, the birth rates, the growth rates, etc. are all the same.

Similar to mice, foxes also rear their young in underground dens. So you will not get any information about the fox kits in the Ecosystem data. If you want some correlations about fox kits, you will have to obtain them by comparing fox numbers over several months. For example, an increase in juvenile foxes indicates a high birth rate at an earlier time. What were the conditions to create that high birth rate? You and your fellow Food Chain colleagues will have to figure this correlation out for yourselves.

Science · Laboratory · Ecosystem · Quest · Laboratory Trials · Ecosystem Trials · Quest Trials
Discussion · Journal · Hall of Fame · Design · Participation · Contacts & Credits

 
© 2011 Dave Volek. All Rights Reserved.