Your browser has javascript turned off or blocked. This will lead to some parts of our website to not work properly or at all. Turn on javascript for best performance.

The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here:

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Brittle star fossils provide insights into when, how and why major evolutionary change occurs in Earth history

brittlestar painting
An artistic reconstruction of Ophiopetagno paicei from the Silurian of Gotland, Sweden. Painting by Joe Petagno.

Present-day biodiversity is the result of millions of years of evolutionary change. Although we can trace back in time most of the major organismal groups using fossils, the very origin of these clades is generally deemed impossible to grasp, hampering our understanding of what drives evolutionary innovations. An international team of paleontologists, including Mats Eriksson and Johan Lindgren, recently discovered 428-million-year old fossils from Sweden that precisely pinpoint the origin of the living brittle stars – a major group of marine invertebrates related to the starfish – to a single pair of temporally consecutive species. This challenges textbook knowledge that last common ancestors of major groups are impossible to find in the fossil record.

The paper is published in Nature’s Communications Biology.