This month's cover highlights the article Adaptively evolved human oral actinomyces‐sourced defensins show therapeutic potential by Shunyi Zhu and colleagues. The scanning electron microscope shows the deformation of the gram‐positive bacterium Bacillus megaterium caused by an oral actinomyces‐sourced defensin – AMSIN (lower panel). The upper panel shows the untreated bacteria. (Scientific image by Bin Gao and Shunyi Zhu, Institute of Zoology, Chinese Academy of Sciences, Beijing, China)