A vertebrate “food chain” fossil has been found in Germany. It was a shark that had eaten an amphibian that had eaten a fish. Scientists compared the fossil to Russian nesting dolls.
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The fossilized trio lived 290 million years ago in the shallow coastal waters of a freshwater lake in the Saar-Nahe Basin of southwestern Germany. The lake had previously been linked to the sea but was landlocked for millions of years before the three animals lived and died.
Several pieces of evidence suggest the animals must have formed part of a single food chain.
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