Contents: The microbes thriving in our bowels Hidaya Aliouche Spotlight Saving the red ape Katie Frimston Bioethics Genome editing: promises and problems John Bryant Fighting flu Saira Hussain 'Controlled variable' and 'control group' Martin Rowland Cultivating clones Liz Sheffield Interface Modelling wildlife corridors: a tool for creating habitat in fragmented landscapes Lydia Cole Upgrade Will examiners penalise my poor English? Martin Rowland Uncoupling mitochondria turns up the heat Katrine Wallis Evaluating experiments The Miller-Urey experiment Adam Hart The placenta Kirsty McIntyre Images of biology Evolution in your garden Kevin O'Dell