Building a baby: The first two weeks

The first few weeks of an embryo's development are vital. Now, new techniques are allowing scientists to learn more about this crucial time than ever before. Read more: https://www.nature.com/articles/d4158… Sign up for the Nature Briefing: An essential round-up of science news, opinion and analysis, free in your inbox every weekday. https://go.nature.com/371OcVF