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Synopsis Our article describes the explosive seed dispersal of the Hura crepitans fruit. Through high-speed video analysis of an exploding fruit, we observe that the seeds fly with backspin as opposed to topspin, which was previously assumed. Backspin orients seeds to minimize drag during flight and consequently increases dispersal distance. The seeds’ dispersal distance is estimated by using results from the seeds of Ruellia ciliatiflora, which are similarly shaped but ∼10 times smaller than those of H. crepitans. We note that the effects of lowering drag on the dispersal distance are more pronounced at higher speeds. We also see that the effect of launch height on the dispersal distance of the seeds becomes less consequential at higher launch speeds. We conclude that the increased dispersal distance due to flying with backspin should improve fitness in colonizing new habitats or escaping disease or predation and that comparisons of the seed dispersal mechanisms across species within the Euphorbiaceae and Acanthaceae might help reveal the adaptive significance of this behavior. 

Abstract This report, summarising work achieved in the context of the LHC Dark Matter Working Group, investigates the phenomenology oft-channel dark matter models, spanning minimal setups with a single dark matter candidate and mediator to more complex constructions closer to UV-complete models. For each considered class of models, we examine collider, cosmological and astrophysical implications. In addition, we explore scenarios with either promptly decaying or long-lived particles, as well as featuring diverse dark matter production mechanisms in the early universe. By providing a unified analysis framework, numerical tools and guidelines, this work aims to support future experimental and theoretical efforts in exploringt-channel dark matter models at colliders and in cosmology.