Skyrmions are stable topological textures with particle-like properties — a mathematical concept that was originally used to describe nuclear particles but has since turned up at all scales. Last year, the presence of skyrmions in the magnetic compounds MnSi and Fe1?xCoxSi was confirmed with neutron-scattering experiments. Here, real-space images are presented of a two-dimensional skyrmion lattice in a thin film of the latter compound. The observed nanometre-scale spin topology might reveal new magneto-transport effects.

Volcanic eruptions release a large amount of sulphur dioxide. This is oxidized to sulphate and can then form sulphate aerosol, which can affect the Earth's radiation balance. Here, past volcanic eruptions and atmospheric conditions are investigated by using sulphur and triple oxygen isotope measurements of atmospheric sulphate preserved in the rock record. The results show that seven eruption-related sulphate aerosol deposition events occurred in the mid-Cenozoic era in the northern High Plains of North America.

It is expected that closely related organisms are more likely to show similar ecological interactions than less related ones. But this has been tested only for certain types of interaction, and in a restricted set of taxa. Now interaction networks have been constructed for 116 different clades of related organisms, across the entire tree of life, and including all types of interaction. The results reveal significant conservatism across the board, including both specialist and generalist species.