Evidence in the Fossil Record

Front

Fossil Noun

---

[fos-il]

Back

Fossil

---

A preserved remain or trace of a living thing from a past geological age, often found embedded in rock.

---

Example: Shows how dinosaur remains become fossils over time, buried in sediment layers.

Front

Sediment Noun

---

[sed-uh-muhnt]

Back

Sediment

---

Small, solid pieces of material that come from rocks or the remains of organisms, settling at the bottom.

---

Example: Sediment layers form as rivers deposit small rock pieces at the bottom of lakes.

Front

Mold Noun

---

[mohld]

Back

Mold

---

A type of fossil that is a hollow area in rock in the shape of an organism or part of it.

---

Example: The image shows a mold fossil, which is a hollow impression left by an organism in rock.

Front

Cast Noun

---

[kast]

Back

Cast

---

A solid copy of an organism's shape, formed when minerals or sediment fill a mold and harden into rock.

---

Example: A cast fossil forms when minerals fill a mold and harden, creating a solid copy of an organism's shape.

Front

Body Fossil Noun

---

[bod-ee fos-il]

Back

Body Fossil

---

A fossil that preserves the actual shape and structure of an organism's body, like bones, shells, or teeth.

---

Example: A dinosaur's body is buried by sediment over time, preserving its bones as fossils.

Front

Petrified Fossil Noun

---

[peh-truh-fahyd fos-il]

Back

Petrified Fossil

---

A fossil in which minerals replace all or part of an organism, effectively turning the remains into stone.

---

Example: A petrified fossil shows minerals replacing an organism, turning it into stone.

Front

Trace Fossil Noun

---

[treys fos-il]

Back

Trace Fossil

---

A type of fossil that provides evidence of the activities of ancient organisms, such as footprints, nests, or burrows.

---

Example: A dinosaur footprint fossil shows evidence of ancient animal activity.

Front

Fossil Record Noun

---

[fos-il rek-erd]

Back

Fossil Record

---

The total number of fossils that have been discovered, providing evidence about the history of life on Earth.

---

Example: This image shows how a dinosaur becomes a fossil over time, illustrating the fossil record.

Front

Microfossil Noun

---

[mahy-kroh-fos-il]

Back

Microfossil

---

A fossil that is microscopic in size and can only be seen and studied with the aid of a microscope.

---

Example: This image shows microfossils, which are tiny fossils visible only under a microscope.

Front

Radioactive Dating Noun

---

[rey-dee-oh-ak-tiv dey-ting]

Back

Radioactive Dating

---

A method of determining the age of an object by using the properties of radioactive atoms that it contains.

---

Example: A graph showing how a radioactive substance decreases over time, helping to date fossils.