The fossil cluster and a diagram showing the position of the lobsters |
This close up of the fossil makes the lobsters a little easier to see |
It was only when they examined the shell closely that they found a series of smaller fossils inside. The Dotternhausen quarry contains a type of rock called gas shale. The shell of the ammonite was so thin that it was translucent, allowing the researchers to see the tiny preserved exoskeletons of three lobsters inside. It was likely that the ammonite died and drifted to the seabed where the soft innards rotted and the lobsters took refuge inside the husk.
It is possible that they were taking refuge from giant marine reptiles whose remains have also been found in the same geological formation. What makes them important is their age. The rocks from the area have been dated to 180 million years old. Previously, the oldest known lobster cluster was just 100 million years old which came from Greenland. These kinds of fossils may not be the most exciting to look at, but they do reveal the origins of characteristics seen in animals today.