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Prehistoric ammonite's 'death drag' uncovered

(China Daily) Updated: 2017-05-12 07:26

LONDON - A team of scientists from the United Kingdom, Germany and Spain has uncovered the "death drag" of a squid-like creature, made about 150 million years ago.

The team, led by paleontologist Dean Lomax, from the University of Manchester, has digitally recreated the fossil using 3-D modeling technology.

The fossil is an ammonite, a type of prehistoric cephalopod related to squid and octopuses, found across the globe, the scientists said this week.

What makes this ammonite stand out is the 8.5-meter-long drag mark it has left behind. The ammonite was already dead when the drag mark was made, making it an extremely rare find, they said.

Lead researcher Lomax said: "With fossils, we usually find body fossils, such as bones, teeth or shells, or trace fossils, such as tracks and burrows. However, the drag mark has not been made by the ammonite in life and does not reflect behavior. Instead, the drag mark was created by the lake's current moving the ammonite shell. It is easy to understand why such fossils have been misinterpreted as the traces of living organisms.

Peter Falkingham, one of the co-authors of this study, said: "We created a virtual model of the fossil by compiling over 600 photographs of the specimen. We then created a video, which shows the drag mark and the preserved ammonite. Such modern digitization techniques, like the photogrammetry method we used, have really revolutionized the way paleontologists can study fossils."

Xinhua

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