Mathematical Model of Sunflower Head (image) University of Arizona Share Print E-Mail Caption This image shows the pattern on the head of a sunflower as generated by a mathematical model of plant growth. Credit Matt Pennybacker, University of Arizona. Usage Restrictions This photo may be used only to illustrate a story about the research described in the accompanying release, How Nature's Patterns Form. Please make sure to credit the image to: Matt Pennybacker, University of Arizona. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.