Evolutionary Search

Name: ______________________   Date: ____________

Use the clues to fill in the crossword.

Across

  1. 1. A period marked by distinctive character or reckoned from a fixed point or event (3)
  2. 2. An amount of time (6)
  3. 5. The responsive adjustment of a sense organ to varying conditions (10)
  4. 6. The remains of a plant or animal that existed in a past geological age and that has been excavated (6)
  5. 7. No longer in existence (7)

Down

  1. 1. The sequence of events involved in the ___ development of a species or taxonomic group (9)
  2. 3. A well-substantiated explanation of some aspect of the natural world (6)
  3. 4. The time required for something to fall to ___ its initial value (8)