Photo by V. Miller
March 15, 2006
Fractals and Fish Scales
The Fractal Model: A New Model to Analyze the Development of Fish Scales
Lucia Mocz, 14, Mililani, Hawaii
Finalist, Discovery Channel Young Scientist Challenge, 2005
Project background: Fish, like trees, have growth rings. A fish's growth rings are recorded on its scales. Lucia read about fractal math as applied to tree rings. She wondered whether the growth rings on fish scales might provide information about the life of an animal, just as tree rings provide information about the life of a plant. She hypothesized that fish scales would follow fractal patterns—geometric patterns that repeat over a variety of ranges.
Tactics and results: Lucia obtained four species of USDA-inspected fish. Using a digital microscope, she obtained micrographs of the scales of each species. She converted these images to grayscale and used a technique called rescaled range analysis to examine the pixel intensity of a cutout section of each image. She calculated a Hurst coefficient to determine whether long- or short-term fractal correlations occurred in the growth of the scales. A Hurst coefficient of 0.5 to 1.0 indicates a highly fractal pattern. The average correlation for the four fish species was 0.7. Mullet had the strongest positive correlation (0.79) and salmon had the weakest (0 .67).
 |
| Photo by V. Miller |
Lucia concluded that rescaled range analysis of fish scales could be an effective means of tracking environmental impacts on fish life.
Read the latest science fair news
Get a science fair tip
Browse a list of science fair topics
Talk Back:
Do you have any comments about this ScienceFairZone? Send them
to us using the form below.
|
SNK RSS Feed 
