Villi Form Patterns within the Gut during Development (image) Harvard University Share Print E-Mail Caption Patterns within the gut progress through several characteristic stages during embryonic development. Credit Images courtesy of L. Mahadevan and Science/AAAS. Usage Restrictions None 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.