Solved cryptogram

Fossils turn up in sedimentary rock, because the heat that makes the other kinds destroys them.

Earth Science Facts, sourced to U.S. Geological Survey.

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What it means

Sediment settles gently, in layers, at temperatures a shell or a bone can survive. Igneous rock arrives as a melt, and metamorphic rock is recooked hard enough to rearrange its own minerals, so neither preserves a body. That is a strong constraint on where anyone can look for the history of life. The fossil record is not a record of the past in general; it is a record of the places where mud was piling up quietly.

The claim comes from U.S. Geological Survey.

Nearby in the collection

The facts either side of this one.

  • NPShard, 74 letters
  • USGSmedium, 72 letters
  • USGSmedium, 73 letters
  • NPSmedium, 73 letters

About as hard as this one

Scored closest to it by the model behind our guide to solving cryptograms.

  • NSIDCmedium, 70 letters
  • NOAAmedium, 72 letters
  • RSCmedium, 75 letters
  • USGSmedium, 79 letters

Every Earth Science Facts cryptogram · All fact collections

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