One of the major items that struck me as I read through the evolutionary biology literature was the fact that natural selection (or more specifically in the case of the overfishing example, directional selection) can cause changes in an observable phenotype that can become apparent within only a few generations.Â I was always under the impression that evolutionary processes operated over a very long period of time and were more or less unobservable at the micro (generational) level.Â However, it seems that my initial assumptions were incorrect, and the fact that a scientist was able to design an experiment that could show the effects of directional selection as well as the corresponding rebounding of a population within just a few generations is amazing.
The next thing I would like to explore is how these processes play out over longer periods of time. The experiment I covered in class lasted 10 generations, and I wonder whether there would be statistically significant differences in the various populations after, say, 100 generations of â€œrecovery.â€Â This would lend more credence to the theory that we could reverse the damage we have done by overfishing large fish populations if we were to stop and give these populations in the wild some time to rebound.
Exploring this experiment as part of the Science Salon helped to prepare me for my initial meeting with my scientific expert.Â During this meeting we determined that our mutual interest was in finding ways to more effectively convey difficult scientific concepts to students as well as find ways to make Biology more engaging and appealing.Â Our initial plan is to develop a simulation that uses Augmented Reality techniques to create an immersive environment that can be used as a teaching tool.
Our initial game plan for developing such a system is as follows:
- Develop a 2D simulator that models the concept of directional selection on a simple population.Â For the purposes of this project we have selected the somewhat famous case of the â€œCepaea nemoralisâ€ snail and its predator, the Song Thrush.Â (http://www.weichtiere.at/Mollusks/Schnecken/drossel.html).Â The simulator will have the following characteristics:
- An environment made up of a heterogeneous background color will be established for our snails.
- Snails of various colors will be introduced and will be able to move around this environment.
- Song Thrush predators will be established and will keep track of how â€œhungryâ€ they are.Â When they reach a certain hunger level they will enter the environment and select the â€œeasiest to spotâ€ snail within a small region.Â The ease of detecting a snail is computed by comparing the snailâ€™s coloring to the coloring of the background.
- Snails that are eaten are removed from the simulation.
- After a predetermined time the remaining snails enter a breeding period.Â Offspring will have coloring that is computed based on the coloring of their parents. Cepaea nemoralis is a hermaphroditic species, so two mating snails act as both mother and father for the next generation.
- Statistics are gathered throughout the simulation, including the frequency and color of snails eaten as well as the coloring and frequency of the surviving snails.
- Once the simulator behaves in a stable and reliable manner, we will work to convert it into a 3D augmented reality installation.Â The AR display will (probably) work as follows:
- A static camera will focus on a tabletop that contains an AR marker tile.
- The marker will serve as the center of the environment and will be detected by an AR computer vision algorithm.
- The augmented video stream will be projected on a screen behind the table.Â This will allow passers by to see themselves standing in front of a table that is teeming with 3D snails and birds locked in an epic evolutionary struggle!
- A series of additional AR tags will be available to allow visitors to interact with the display.Â These can include tags that can be held up to display:
- Current statistics on the color values & frequency of eaten snails
- Current statistics on the color values & frequency of surviving snails
- Possibly allow visitors to â€œdropâ€ new snails into the simulation or to start off the simulation with customized starting parameters