The vertical fossil and the exploding ichthyosaur theory

Ancient seagoing animals did not explode nearly as often as scientists believed, according to a new study called Float, Explode or Sink: Postmortem Fate of Lung-breathing Marine Vertebrates.

The authors, an all-star team of palaeontologists, pathologists and forensic anthropologists [one of them, Achim Reisdorf, is pictured here] from six institutions in Switzerland and Germany, deflated a hypothesis that had for years lain basking in the sun.

They were addressing the underlying question: why are some ichthyosaur skeletons scattered across an expanse of sea floor, while others remain fairly intact?

The current adventure started with the discovery of an ichthyosaur skeleton, embedded in rock, in northern Switzerland. This skeleton was oriented weirdly, compared with most such fossils: aligned vertically, with its head down, its feet up.

Someone hypothesised that "an explosive release of sewer gas" had "propelled the skull into the sediment"….

So begins this week's Improbable Research column in The Guardian.

BONUS: For something completely different—an upside-down, head-exploding take on this same subject—behold this video: