How fossils form · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

How fossils form

Science · Earth's Systems · ages 7-8
Name ______________________   Date ____________

  1. Which object can become fossil evidence of an ancient animal?

    • A mark made by a raindrop
    • A seashell
    • A crack made by freezing water

  2. In the shell-fossil model, what happens first?

    • The animal dies
    • The shell is buried in mud
    • The layers become solid rock

  3. A shell fossil can preserve a mark of the shell's shape in rock.

    Circle one:   True   False

  4. A dead fish lies on a muddy lake floor. Which event gives its remains a better chance of being preserved?

    • Mud quickly covers the remains.
    • Moving water scatters the remains across the lake.
    • Other animals eat all the remains before burial.

  5. In the shell-fossil model, which stage comes directly after the shell is buried?

    • The surrounding layers become rock
    • The animal dies and leaves its shell
    • More layers build up

  6. These cards name fossils. How many are body fossils rather than traces of activity?

    BoneShellFootprintLeaf print

    Answer: ______________

  7. Jax leaves an ordinary rock in sunlight for an afternoon and calls it a fossil. Which fact checks his idea?

    • Sunlight changes every rock into the remains of an ancient animal.
    • Any old rock counts as a fossil, even without evidence of ancient life.
    • A fossil must preserve evidence of ancient life.

  8. Mia finds an ancient leaf print preserved in rock. What is it?

    • A crystal growing inside a crack
    • A leaf fossil
    • A scratch made by a digging tool
LightMySky · lightmysky.comW1-mt_mwirOvigWD-s1

Answer key

For grown-ups. Fold this page away before handing over the rest.

How fossils form W1-mt_mwirOvigWD-s1

  1. A seashell · A seashell came from an animal. Raindrop marks and freezing cracks are not remains or traces of life.
  2. The animal dies · This shell model begins when the animal dies. Burial and rock formation follow.
  3. True · A shell or a mark of its shape may be preserved as the surrounding layers become rock.
  4. Mud quickly covers the remains. · Burial can protect remains from being eaten or washed away. It gives preservation a better chance but does not promise a fossil.
  5. More layers build up · Burial is followed by more layers building up. Rock formation comes later in this model.
  6. 3 · Bone and shell preserve body parts. A leaf print preserves body shape. These three are body fossils. A footprint records activity.
  7. A fossil must preserve evidence of ancient life. · Sunshine alone does not create preserved remains or traces of ancient life.
  8. A leaf fossil · The leaf was part of a plant. Its preserved ancient print is fossil evidence of life.
Worksheet · LightMySky