New fossil suggests the body part was used for fighting, swimming
Ancient sea scorpions were hacks.
Some of the marine creatures had a thin, serrated spine on the tip of their tail — and that tail was surprisingly flexible, based on a 430-million-year-old fossil found in Scotland. Slimonia acuminata may have had the range of motion to strike large predators and prey, researchers report online April 18 in American Naturalist.
Scientists had thought that the ancient animals largely used their tails for swimming, primarily flapping them up and down like today’s lobsters and shrimp do and, to a limited degree, side to side like a rudder. But the tail on the new, well-preserved fossil curls dramatically to the side — a flexibility not seen in other sea scorpion specimens.
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