Fossils Show Relative Age Practice Test

A student studies two rock columns from nearby locations. Fossils were deposited when the layer formed.

Column X (top to bottom):

• X1: Fossil E (ammonite-like spiral)
• X2: Fossil F (clam shell)
• X3: no fossils shown

Column Y (top to bottom):

• Y1: no fossils shown
• Y2: Fossil F (clam shell)
• Y3: Fossil G (bone fragment)

Which statement is best supported by the fossil evidence?

Two nearby outcrops show undisturbed rock layers. Fossils were deposited when the layer formed.

Column A (top to bottom):

• A1: Fossil S (spiral shell)
• A2: Fossil T (fish)
• A3: Fossil U (leaf)

Column B (top to bottom):

• B1: Fossil V (bird footprint)
• B2: Fossil T (fish)
• B3: Fossil W (coral)

Which conclusion is best supported by the fossil evidence?