Fossil Records CW 1

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Across
  1. 4. A scientist that studies the fossil record to better understand life on Earth.
  2. 5. time when much of Earth’s surface is covered by glaciers
  3. 7. A fossil that provides evidence for organisms transitioning from living in water to land.
  4. 8. oldest era of the Phanerozoic eon
  5. 9. similar cells that work together and perform a function
  6. 14. longest unit of geologic time
  7. 17. Groundwater fills pore spaces in animal or plant remains and deposits minerals. Most dinosaur body fossils are formed this way.
  8. 20. species that existed on Earth for a short length of time, was abundant, and inhabited many locations
  9. 22. middle era of the Phanerozoic eon
  10. 24. most recent epoch, which began 10,000 years ago
  11. 26. youngest era of the Phanerozoic eon
  12. 30. dominant Mesozoic vertebrate that walked with legs positioned directly below its hips
  13. 31. Evidence that organisms have changed over long periods of time.
  14. 34. Hollow space left in a rock by animal or plant remains that have dissolved.
  15. 37. study of similarities and differences among structures of living species
  16. 38. refers to a side or a sideways direction
  17. 39. Impression or other preserved sign of activity such as feeding, scratching, burrowing, walking, or resting.
Down
  1. 1. subdivision of an era
  2. 2. Preserved remains or traces of ancient plant and animal life.
  3. 3. atoms of the same element that have different numbers of neutrons
  4. 6. body part found in multiple species that performs a similar function but differs in structure
  5. 10. numerical age of a rock or other object
  6. 11. preserved remains or evidence of ancient living organisms
  7. 12. Layers of sedimentary rock that compile and compress over time that can trap fossils within them.
  8. 13. process by which an unstable element naturally changes into another stable element
  9. 15. first epoch of the Quaternary period
  10. 16. subdivision of a period
  11. 18. Preserved remains of the plant or animal itself, or the preserved parts of the animal or plant like bones, teeth, and shells, or the imprint of parts of the animal or plant.
  12. 19. body part found in multiple species that is similar in structure and position but different in function
  13. 21. set of all the fossils ever discovered on Earth
  14. 23. fossil copy of an organism in a rock
  15. 25. chart that divides Earth’s history into different time units
  16. 27. process of matching rocks and fossils from separate locations
  17. 28. scientist who studies fossils
  18. 29. fossilized carbon outline that forms when pressure drives off the gases and liquids from a buried organism
  19. 32. the age of rocks and geologic features with respect to other rocks and features nearby
  20. 33. when all individuals of a species have died
  21. 35. subdivision of an eon
  22. 36. time required for half of the parent isotopes to decay into daughter isotopes