Over the weekend I came across a wonderful illustration in a new paper that I’ve goosed up (thanks, open access!). The subject of the paper is the way our proteins work together. Many proteins work by first joining together with other proteins to form what are known as complexes. Which naturally raises the question: how did different protein complexes evolve from common ancestors?

To attack this question, Dutch researchers decided to compare two species in which protein complexes have been very carefully catalogued: yeast and humans. Yeast are fungi, and humans are animals; fungi and animals descend from a common single-celled ancestor that has been estimated to have lived 1.5 billion years ago. The Dutch researchers identified