Modal density and coherence in science dissemination: Orchestrating multimodal ensembles in online TED talks and youtube science videos

As science communication goes beyond the traditional borders of academia, new dissemination genres emerge. This paper presents a multimodal analysis two online videos uploaded to YouTube: recorded TEDx talk and PBS Space Time video. We have determined existence layers modes in videos: embodied filmic modes. The former are deployed by speaker, while latter added ensemble during postproduction editing. Our sheds light on three main aspects this orchestration: modal density, coherence, genre definition. findings show that more modally dense as result incorporation into ensemble. In addition, we also find use requires some degree expertise know-how order keep coherence short, video shows higher density coherence. conclude at different stages development digital genres.