Figure 2. Proposed Model: Emu wing buds contain muscle progenitor cells with dual somite-derived myogenic and lateral plate mesodermal signature. (IMAGE) Tokyo Institute of Technology Caption Proposed Model: Emu wing buds contain muscle progenitor cells with dual somite-derived myogenic and lateral plate mesodermal signature. These cells undergo cell death, which hinders the normal development of wing muscles. As a result, the lack of mechanical stress from muscle contractions leads to shortened bones and asymmetric fusion of skeletal elements. Credit Professor Mikiko Tanaka / Nature Communication Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND 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.