How is geologic Time divided?

 I can distinguish the different geologic time periods.

 Tell me about last week…………… What science topics did we discuss?????????????

 Page 273  Geologic Time is divided into  Eon  Era  Period  epoch

 Eons are the longest subdivision on the geologic time scale.  Based on the abundance of certain fossils

 Era’s are the second longest subdivision  Marked by major, striking, worldwide changes in the types of fossils present.

 Periods are units of geologic time characterized by the types of life existing worldwide at that time.

 Epochs are 4 th on the geologic time scale for time.  Characterized by differences in life forms  Can vary from continent to continent Usually referred to as early, middle or late

 By the various rock layers and the fossils found in them.

 In your notes  Take about 7 minutes to draw the geologic time scale. (Page 273) you may color if time.

 Changes through time…(274)

 Species is a group of organisms that normally reproduces with only other members of their group.

 Natural Selections– a process by which organisms with characteristics that are suited to a certain environment have a better chance of surviving and reproducing than organisms without these characteristics.

 Chapter 10 section 1 read pages (for understanding) Quiz tomorrow…..Reading/Comprehensi on quiz….  Exit Quiz

 1. How many different units is the geologic time scale divided into?  2. Name the different units of geologic time.