Evolution-Are they among us?

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Across
  1. 4. the dying out of a large number of organisms over a relatively short period time
  2. 6. the process by which the age of a fossil or rock is determined through measuring the decay of radioactive isotopes
  3. 7. a species from which two or more species have descended
  4. 9. a subdivision of a geologic eon-an earl is the second-longest period of geologic time
  5. 11. a method used to identify the approximate age of a rock layer by determining the ages of the layers above and below it
  6. 12. the process of bringing back organisms that have gone extinct
  7. 13. both the inside and outside structure of an organism
  8. 14. the process by which an embryo forms and develops
Down
  1. 1. an organism preserved in rock that is common of a particular time or environment and used to help identify geologic periods
  2. 2. all know fossils in the Earth's history arranged in chronological order
  3. 3. a developing animal that hasn't hatched or been born yet and is in the earliest stages of growth when its basic structures are being formed
  4. 5. a scientist who studies the fossils of prehistoric organisms
  5. 8. the geologic age of a fossil as defined by other rocks or fossils
  6. 10. the study of fossilized animals and plants
  7. 14. the gradual change in living things over many generations due to changes in inherited traits