Here are my Honours Projects for 2007.
IMPORTANT: Please come and see me regarding any project you intend doing before selecting that project.
The 'Daisyworld' model of Ecologist James Lovelock, first published in 1983, is a simple model of planetary self-regulation, bi-stability and homeostasis. It is considered a 'parable' of planetary self-regulation, achieved via feedback between life and its environment. The original model had a simple gray plant, populated by two species of daisy: one black and one white. The number and proportion of the daisy species alter their local temperature in opposite directions (a white daisy reflects solar radiation, a black one absorbs it). The Daisyworld model demonstrated a global regulation of planet surface temperature in response to changes in the amount of solar radiation falling on the planet. This is achieved by a feedback loop between planetary albedo and daisy growth rates.
In 1998, a paper by Robertson and Robinson argued that if there were variation of optimum growth temperature within the daisy population, then the population should adapt towards the prevailing conditions. Robertson and Robinson showed that high rates of adaptation destroyed temperature regulation in Daisyworld. Lenton and Lovelock responded in a 2001 paper, claiming that with bounds on the range of adaptation, regulation was maintained. However, their model showed wide variation for different runs, with the mean of 10 separate runs showing only 'minor temperature regulation'.
In this project you will develop an evolutionary Daisyworld model in order to test the effects of adaptation on self-regulation. The goal is to better understand the effects of mutation rate and adaptive bounds on this model.
The 2006/2007 summer cricket season was imbued with controversy as Cricket Australia banned the 'Mexican wave' across stadiums in Australia. Many fans reacted angrily, defying the new laws, potentially facing eviction from the ground and heavy fines. A campaign to 'save the wave' was quickly begin, with commentators saying the ban had gone too far, ruining people's enjoyment of the game, and participation as spectators.
The rational given to banning the Mexican wave is that, when throwing their arms in the air, some people choose to throw objects that fall on the people below, potentially risking serious injury.
For this project you will develop an agent-based model of crowd behaviour, designed to test theories about the initiation and propagation of the Mexican wave in stadium crowds. You will need to model agents (representing the people in the stadium) as well as the physical layout of the stadium itself.
Some questions to be asked of the model:
The so-called 'superformula' is generic geometric transformation developed by the engineer Johan Gielis. It is based on the idea that relatively simple parameterised formula can represent a wide variety of geometric shapes. For example, the circle, square, and ellipse are all members of the set |x/a|^n + |y/b|^n = 1. The superformula can represent a large number of natural profiles, particularly those found in plants. The original formulation was confined to two-dimensional space. The aim of this project is to develop a three-dimensional modelling system based on the use of the superformula. Some possibilities include the use of generalised cylinders (using superformula representations for profile and carrier curves), or implicit surface representations. The system developed should be applied to practical modelling of a variety of organic shapes.
For this project you will need to have successfully completed CSE3313 Computer Graphics. Knowledge of OpenGL and a hunger for mathematical visualisation would also be helpful.
Reference: Gielis, J. "A generic geometric transformation that unifies a wide range of natural and abstract shapes", American Journal of Botany 90(3): 333-338. 2003.
Important questions that will be addressed by the student include:
What are the necessary and sufficient conditions for the evolution of virtual
ecosystems?
How does group selection compare against individual selection under different
circumstances?
New computer graphics visualisation tools will need to be developed
in order to interpret the results of the simulations conducted during
the course of the project. Students will require a sound programming
knowledge (C/C++ preferred, CSE2305, CSE3308) and experience with computer
graphics programming (OpenGL, CSE3313) and multimedia (CSE2325/3325).
Wade, M.J. 1976. Group selection among laboratory populations of Tribolium. Proceedings of the National Academy of Sciences U.S.A. 73: 4604—4607
Wade, M.J. 1977. An experimental study of group selection. Evolution 31: 134—153
Some introductory reading:
Dawkins, R., The Blind Watchmaker. 1987, New York: W.W. Norton & Co.
Epstein, J.M. and R. Axtell, Growing Artificial Societies, Social Science from the Bottom Up. 1996, Washington D.C.: Brookings Institution & MIT Press.
Yaeger, L. Computational Genetics, Physiology, Metabolism, Neural Systems, Learning, Vision and Behavior or Polyworld: Life in a New Context. in Artificial Life III. 1992: Addison-Wesley