Correction to: Nature https://doi.org/10.1038/s41586-020-2024-3Published online 19 February 2020

In this Article, owing to errors during the production process, the text ‘n = 25,202’ was erroneously obscuring the top left of Figs. 1a and 2a (in Fig. 1a, this text was duplicated, and in Fig. 2a, this text was inadvertently added). These figures have both been corrected online.