Geological Time Crossword Puzzle

QUESTIONS LIST:

• period : one of the units of geologic time into which geologist divide eras
• mesozoic era : known as the "age of reptiles"
• clam : invertebrate with shell during cambian time
• dinosaurs : animal that first appeared during the triassic period
• cycad : seed plants with a long fossil history during the triassic period
• vertebrate : an animal with a backbone
• mammal : a warm blooded vertebrate that feeds its young milk
• pre cambrian time : includes most of earth's history
• era : one of the three long units of geologic time between precambrian and the present
• paleozoicera : a great number of different kinds of organisms evolved during this time
• amphibian : a vertebrate that lives part of its life on land and part in the water
• devonian period : animals began to invade the land during this time
• invertebrate : an animal without a backbone
• shark : group of fish that have 5 to 7 gill slits on each side
• epoch : subdivisions of the periods of the geologic time scale
• pangaea : earth's continents move together to form great land mass
• conifer : a tree that bears cones during the permian period