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The model I choose to look at was Mimicry. One type of mimicry known as Batesian mimicry is the situation where a harmless species evolves to looks similar to a different species which isn't harmless in order to avoid a common predator. One example of Batesian mimicry is depicted by monarchs and viceroys. They are very similar in coloring even though they are different species, one is a butterfly while the other is a moth. The monarch butterflies are unpalatable to birds and so the birds avoid the monarchs based on coloring. The viceroy moths avoid being eaten if they are similar in color to the monarchs.

The model demonstrates how this complex behavior might have evolved. It begins with 450 monarchs and viceroys. The monarchs are represented by the letter "x" and are colored red, while the viceroys are represented by the letter "o" and colored blue. There are also 75 birds, the common predator to the monarchs and viceroys. When a bird encounters a monarch or a viceroy it eats the butterfly or moth unless it remembers that the butterfly is unpalatable. As the butterflies/moths are eaten they are regenerated based on how many butterflies/moths already exist,the carrying capacity is 225. When a butterfly/moth reproduces there is the chance that it could result in a mutant which has different coloring.

The model allows you to varry how long a bird retains the memory that a particular color is unedible and it allows you to vary the number of memories a bird can hold at one time. In addition the mutation rate of the butterflies and moths offspring can be varied.

This model is similar to the Langton's Ant model because it shows how complex behavior such as mimicry culd have arisen from simple interactions between the birds, butterflies and moths. Both the Langton's Anot model and the Mimicry model at first seems to need complex explanations for the behavior demonstrated but in fact the behaviour can be accounted for in terms of simple interations between simple things. The organisms in both only require a simple set of instructions and the ability to respond to and change their environment. The main difference bewteen the two models is that the Mimicry model is not completely predictable and deterministic because the mutations introduce randomness into the model.