The Sea Squirt, <i>Ciona intestinalis</i> (IMAGE) University of Arizona Caption Its simple body organization and close kinship to vertebrates make the sea squirt Ciona an attractive model organism to study the genetic underpinnings of heart development. Credit Daniel Stolte/UANews Usage Restrictions Usage only permitted with reference to this news release. Photo credit must be indicated. License Licensed content 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.