Which dating method determines the age of a fossil by comparing its position with fossils in other layers?

• A. Geologic time scale
• B. Relative dating
• C. Radioactive dating
• D. Fossils

Answer: (B)

Determining age by the fossil’s position in rock layers is relative dating. In undisturbed sedimentary sequences, newer layers pile on top of older ones, so fossils found in deeper layers are older than those in higher layers. By comparing where a fossil sits with other layers and the fossils they contain, you can place it in an order along a timeline without assigning an exact year. Using index fossils—fossils known to exist for short, specific time spans—helps sharpen this relative placement.

The geologic time scale is a reference framework for time periods, not a dating method by itself. Radioactive dating gives numerical ages by measuring isotopic decay, not just order. Simply naming fossils isn’t a dating method, though fossils can aid relative dating.