Practice problem

Fossils (Evidence of Evolution) — Overview & Examples

The image displays a stromatolite with many thin layers of orange, red, brown, and green. — Stromatolites (Snowslip Formation, Belt Supergroup, Mesoproterozoic, 1.44 Ga; Glacier National Park, Montana, USA) 3 by James St. John, CC by 2.0 via Wikimedia

Stromatolites are formed when layers and layers of film-forming bacteria collect sediment and turn into a fossil. Stromatolites are some of the oldest fossils ever, with some being older than 3.5 billion years. Why would finding a stromatolite contribute a lot to the fossil record? Select all correct answers.