To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Movie 4. Retrograde heartbeat showing sequential closure from the anterior to the posterior end. Differentiation and function of cardiac valves in the adult Drosophila heart Christian Meyer, Maik Drechsler, Heiko Meyer, and Achim Paululat Journal of Experimental Biology 2023. 226:None-None; doi: 10.1242/jeb.245839 Download Original Video