Computer simulation is the process by which some type of physical phenomena is modeled within the computer. Unlike physical simulations, computer models can be repeatedly executed, thus saving time and money. Simulations are used in science, industry, military, and other important fields. Object-Oriented Physical Modeling is the approach to simulation that will be adopted in this project.

The biological sciences often use simulations. By simulating the natural environment, trends can be realized and knowledge can be gained about our surroundings. A deeper understanding of an organism can be attained by simulating that organism in various conditions. Variables can be changed and the simulation can be run again. In the physical realm, this process could take years versus days or hours on a computer.

The Helicoverpa moth is native to Australia and is the moth being simulated in this project. Its life cycle consists of the following stages: egg, larva, pupa, and adult. Figure 1 shows the life cycle in simple graphical form. Eggs are laid on young plant shoots or the fruiting part of crops. Eggs take from five days to two weeks to hatch. The larva or caterpillar stage is next and normally lasts about three weeks. This is when moths cause most of the damage to clover, corn, cotton, sunflowers, tomatoes, and various cereals. According to Jo Brewer, "[moth larvae] consume enough greenery to increase [their] weight as much as one thousand to ten thousand times" (18). The pupa (commonly referred to as the cocoon) is formed next. The amount of time a moth spends as a pupa varies from a few days to several months. The adult emerges from the cocoon and is able to fly within minutes. The whole cycle takes from 35 to 75 days.

Flight patterns of the Helicoverpa are determined by environmental characteristics such as temperature, wind speed, and wind direction. If these patterns can be recognized, then the pests can be curbed and both money and crops can be saved. One method of pin-pointing these flight patterns is to simulate the moths, their environment, and environmental aspects including rain, temperature, crop growth, etc. using the concepts of Object-Oriented Physical Modeling. From the simulation output, a better understanding of moth behavior emerges.

In the area of simulation and Object-Oriented Physical Modeling:

• Paul Fishwick

In the area of Helicoverpa moth research:

• Martin L. Dillon
• Gary P. Fitt

See Literature Review and References for detailed citations.