Study of puzzling fossils confirms they came from an animal

NEW YORK (AP) — Scientists say they’ve confirmed that puzzling fossils from more than 500 million years ago are traces of an animal.

That would make it one of the earliest known creatures.

The fossils are impressions in rock: oval shapes with internal lines, looking somewhat like a leaf imprint densely packed with veins. First described in 1947, they are found in Australia and Russia.

Scientists have debated what kind of organism left the impression. Nowadays, most experts believe it was an animal. New evidence for that idea was released Thursday in the journal Science. Researchers found a chemical signature characteristic of animals.

It’s not clear when the creature lived, but some of its fossils are 558 million years old.