'Ghost' fossils preserve haunting record of ancient life on a hellish Earth

Ghostly imprints of very tiny "nannofossils" can offer a valuable window into our planet's past — and hint at its possible future.

'Ghost' fossils preserve haunting record of ancient life on a hellish Earth
Ghostly imprints of very tiny "nannofossils" can offer a valuable window into our planet's past — and hint at its possible future.