Some fossil ammonites show evidence that they had been fatally bitten. Lyme Regis Museum Education Officer - Chris Andrew, Geologist - Paddy Howe, Trustee - Chris Paul and Steve Donovan have investigated who the culprit might have been. Their research has shown that single pieces of shell, which extend almost symmetrically on either side and usually reach the umbilical seam on one side, are missing.
The damage lies in a position that would allow a predator to sever attachment muscles and remove the body from the shell more easily. Lack of shell chips preserved adjacent to damaged ammonites precludes scavenging or post-burial crushing as causes of the damage. Ammonites were caught in the water column, manipulated into a horizontal position and then bitten at a precise point.
The most likely predator was an active swimmer, with the capability to hold and manipulate a smooth, possibly slippery, ammonite shell. Their conclusion was that the damage is consistent with bites made by robust, parrot-like, squid jaws.
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