Megafauna Extinction & De-Extinction · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Why Did the Mammoths Disappear?

Science · Dinosaurs & Paleontology · ages 13-14
Name ______________________   Date ____________

  1. Which environment has preserved mammoth remains containing ancient DNA for thousands of years?

    • Desert sand dunes
    • Siberian permafrost
    • Ocean sediment

  2. What does the 'overkill hypothesis' say caused megafauna extinction?

    • Human hunting reduced their populations
    • Rapid climate warming melted their habitat
    • A meteor impact wiped them out

  3. Scientists can take a frozen mammoth's DNA and grow an exact clone of it today.

    Circle one:   True   False

  4. A frozen mammoth carcass with preserved hair, DNA, and stomach contents can give evidence about which of these?

    • Its fur color and diet
    • The exact day it died
    • What language ancient humans spoke

  5. Mammoths survived on Wrangel Island about 6,000 years longer than on the mainland. What can these extinction dates alone tell us about the cause?

    Mainlandmammoths10000WrangelIslandmammoths4000
    • The climate hypothesis, since islands are colder
    • Neither hypothesis, since island mammoths were a different species
    • The dates alone do not establish a cause

  6. Mainland mammoths went extinct about 10,000 years ago. Wrangel Island mammoths survived until about 4,000 years ago. How many more years did the island mammoths survive?

    Mainlandmammoths10000WrangelIslandmammoths4000

    Answer: ______________

  7. One site has hunting weapons with mammoth remains. At another, mammoths declined as pollen shows their feeding habitat shrank during warming, before known human artifacts. What is the best conclusion?

    • The evidence is contradictory and should be ignored
    • Climate change alone explains all mammoth extinctions everywhere
    • Hunting and climate may matter in different places

  8. A news article says 'scientists will bring back the exact woolly mammoth species using cloning.' What is misleading about this claim?

    • Mammoths were never really extinct
    • An elephant with mammoth traits is not an exact clone
    • De-extinction has already fully succeeded
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Answer key

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

Why Did the Mammoths Disappear? W1-mt_tGZ2sMzMGz-s1

  1. Siberian permafrost · Frozen permafrost keeps DNA from breaking down as fast as warmer environments do.
  2. Human hunting reduced their populations · The overkill hypothesis blames human hunters, not weather or an impact.
  3. False · Recovering a DNA sequence does not supply a living cell with a usable nucleus for cloning. No exact mammoth clone can be grown from the preserved DNA today.
  4. Its fur color and diet · Hair and genes can give clues to coat colour. Preserved stomach contents provide evidence of diet.
  5. The dates alone do not establish a cause · The gap shows different extinction times. It does not prove hunting or climate caused either loss.
  6. 6000 · 10,000 minus 4,000 is 6,000 years longer.
  7. Hunting and climate may matter in different places · One site supports hunting; the other supports habitat change. Their relative roles may differ. Missing artifacts do not prove humans were absent.
  8. An elephant with mammoth traits is not an exact clone · The proposed route edits elephant DNA to copy selected mammoth traits. That differs from cloning a complete mammoth.
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