Uri Wilensky

Uri Wilensky, Professor

Sunflower Biomorphs: How can artificial selection drive the emergence of beauty? April, 2006

NetLogo agent-based modeling environment, 14" x 14" print as well as interactive NetLogo simulation

Artist’s Statement:

This interactive simulation is loosely based on the ideas in Richard Dawkins' "The Blind Watchmaker" (1986) where he discusses evolving simulated insects.

In this simulation, the user is presented with a series of "flowers" that are drawn based on four separate "gene" values. For example, if flower A has a "num-color" value of 3 and flower B has a "num-color" value of 2, then flower A would be drawn with more colors. These 4 variables are thus the genotype of each flower-like creature, and the drawing, based on those numbers, is the phenotype. If the user clicks on a flower (or "biomorph"), then all the flowers are erased and the chosen biomorph would be used as the basis for a new population of biomorphs. Each variable is mutated slightly in the new generation (representing the inheriting of a slightly higher or lower value for the genotype), and these mutated values would be used in the new population of the biomorphs. In this manner, the new generation of biomorphs resembles the previously chosen biomorph, with some variation. For example, if you chose a biomorph with a large number of colors, then, because next generation biomorphs are all modified versions of the chosen biomorph, they all would tend to have more colors than the previous generation.

The biomorphs vary along four variables--num-color, step-size, size-modifier, and turn-increment--and not nine. The user is presented with a number of flowers. By clicking on a flower, the user can choose the type of flower that will populate the next generation. If ASEXUAL? mode is OFF, the user picks two biomorphs instead of just one; the next generation will be produced by selecting one of the values for each of the four genotype variables from either one of the parents.

The framed print is part of an exhibit mounted at the NICO building titled:

A Patchwork of Complexity: Agent-Based Models of Emergent Phenomena

by Uri Wilensky and Michael Novak

The exhibit description is:

This "patchwork" is constituted of thirteen squares, each of which is a visualization of an agent-based model of a complex system. A fundamental way to understanding complex systems is to break the overall system pattern down into a set of independent parts (known as the agents). Each agent has its own properties and rules of behavior. When the model runs, each agent follows its rules of behavior, moving and interacting with other agents. The emergent phenomenon is the resultant pattern that arises from these movements and interactions. Emergent phenomena span a wide range of domains. They can include bird flocks arising from individual bird behavior, chemical reactions arising from the behavior of molecules or atoms, economic indicators arising from the behavior of many buyers and sellers, geographic or climatic changes arising from the interaction of topographic features and human outputs, or language change as resultant from the speaking and listening of millions of people. By modeling these phenomena using the agent-based approach, we can gain insight into how micro level interactions give rise to many of the macro patterns we observe in nature and society.

Jurors’ Comments:

"This colorful representation of evolution shows the diversity that accompanies slight changes or mutations in species. It is a visual representation of what Darwin himself postulated; it’s detailed and interesting."

"Being fractal is in these days, didn’t you know? Of course Biology has known that for 3.8 Billion years and counting – can we count on you to be fractal too?"

"This eye-catching piece is an interesting representation of the mathematical model of genetic diversity and evolution. A carefully planned work of art."

"Proves finally that beauty emerges from asexuality."