Life Changed Over Time · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

How Life Has Changed

Science · Dinosaurs & Paleontology · ages 10-11
Name ______________________   Date ____________

  1. What is a fossil?

    • A pretty rock someone painted to look old
    • The bones of an animal that died last week
    • The preserved remains or shape of a living thing from long ago

  2. Which of these is real evidence that life has changed over time?

    • A drawing of a dragon in a storybook
    • Fossils of animals that look different from anything alive today
    • A photo of a dog taken last week

  3. Which list shows the order of the slow change from dinosaurs to birds?

    • Feathered dinosaur, bird, dinosaur, early bird
    • Dinosaur, feathered dinosaur, early bird, bird
    • Bird, early bird, feathered dinosaur, dinosaur

  4. What can scientists learn from a fossil?

    • The exact day the animal died
    • Only the color of the animal's skin
    • How it looked and how it changed

  5. Two fossils found in the same rock layer probably lived at about the same time.

    Circle one:   True   False

  6. Zara compares a fossil bird footprint with a modern heron's footprint. Both show three forward-pointing toes. What does this match tell her?

    • The fossil footprint must be a fake
    • Bird feet have never changed in any way
    • The ancient bird's foot worked much like the modern bird's foot

  7. Fossils show that early feathered dinosaurs shared many features with which living animals?

    DinosaurFeatheredEarly birdBird
    • Insects
    • Birds
    • Fish

  8. A shell fossil is found 12 meters down in the rock. A leaf fossil is found 3 meters down. Which fossil is probably older?

    • The shell fossil, because it sits deeper
    • The leaf fossil, because it is closer to the top
    • They are the same age, because they were found on the same day

  9. Mia says fossils are like pages in a book about life. What does she mean?

    • Fossils have words printed on them
    • Fossils are made of paper
    • Each layer records a different time, so reading them in order shows how life changed

  10. Ben finds a seashell fossil in a deep rock layer and a leaf fossil in a layer near the top. Which fossil is probably older, and why?

    • They are exactly the same age, because they were found together
    • The seashell fossil, because deeper layers formed earlier
    • The leaf fossil, because leaves are lighter than shells
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Answer key

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

How Life Has Changed W1-mt_gTDqxYkLs9-s1

  1. The preserved remains or shape of a living thing from long ago · A fossil is what a living thing from long ago left behind: remains or a shape preserved in rock.
  2. Fossils of animals that look different from anything alive today · Evidence about ancient life has to come from ancient times, and fossils are exactly that.
  3. Dinosaur, feathered dinosaur, early bird, bird · The slow change ran from ancient dinosaurs to the birds of today, with feathered dinosaurs and early birds in between.
  4. How it looked and how it changed · Fossils preserve shapes of bones or shells, so scientists can compare them with living things today.
  5. True · One layer was laid down in one stretch of time, so fossils from the same layer lived at about the same time.
  6. The ancient bird's foot worked much like the modern bird's foot · A matching shape suggests a matching job: both birds walked and stood on the same kind of three-toed foot.
  7. Birds · Feathers, hollow bones, and similar skeletons link early feathered dinosaurs to birds alive today.
  8. The shell fossil, because it sits deeper · Deeper layers formed earlier, so the fossil 12 meters down is probably older than the one 3 meters down.
  9. Each layer records a different time, so reading them in order shows how life changed · Each rock layer holds fossils from one stretch of time, so the layers in order tell the story of how life changed.
  10. The seashell fossil, because deeper layers formed earlier · Deeper layers were laid down earlier, so the fossil in the deeper layer is probably the older one.
Worksheet · LightMySky