The Best Crossword Puzzle Maker Online
Powered by BrightSprout
Save Status:
or to save your progress. The page will not refresh.
Controls:
SPACEBAR SWITCHES TYPING DIRECTION
Answer Key:
Edit a Copy:
Make Your Own:
Crossword Word Search Worksheet
Rate This Puzzle:
Log in or sign up to rate this puzzle.

Life Science: Chapter 8

Across
The period in the geologic time scale from the formation of the Paleozoic era, from about 4.6 billion to 542 million years ago.
The theory that explains how large pieces of the Earth's outermost layer, called tectonic plates, move and change shapes
The standard method used to divide the Earth's long natural history into manageable parts
The species of hominids that include modern humans and their closest ancestors and that first appeared about 100,000 to 160,000 years ago
The geologic era that lasted from 251 million to 65.5 million years ago; also called the Age of Reptiles
Describes a species that has died out completely
Down
Any method of determining whether an event or object is older or younger than other events or objects
Any method of measuring the age of an object or event in years
The geological era that followed Precambrian time and that lasted from 542 million to 251 million years ago
The most recent geologic era, beginning 65 million years ago; also called The Age of Mammals.
A type of primate characterized by bipedalism, relatively long lower limbs and lack of a tail.
The trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock.
A type of mammal characterized by opposable thumbs and binocular vision