ES2901  Observe how fossils can form.

This animation shows the formation of a cast and mold, one way that fossils can form. Casts are copies of fossilized plants or animals. Molds are hollow impressions of the fossil. This process takes thousands or millions of years.

  !   Click the image to see the animation. Use the movie controls to step through or replay the animation.
Jennifer Loomis, TERC