Figure CaptionsFigure 1. Cumulative step curves of preprints addressing the COVID-19 epidemic posted to a) bioRxiv, b) medRxiv and c) arXiv preprint servers over time. Search terms used covered ”coronavirus”, ”coronaviruses”, ”ncov”, ”SARS-CoV-2”, and ”COVID-19”. Colours denote categorisation from preprint metadata, as defined and classified by each preprint server. Interactive, hyperlinked versions of these figures are available at https://lbrierley.github.io/cov_preprints