Essential Knowledge 1.C.1

Speciation and extinction have occurred through the Earth’s history.

Speciation rates can vary, especially when adaptive radiation occurs when new habitats become available.

Species extinction rates are rapid at times of ecological stress Illustrative examples include:

• Five major extinctions (note: the names and dates of these extinctions are beyond the scope of this course.)
• Human impact on ecosystems and species extinction rates

Students should be able to:

LO 1.20 Analyze data related to questions of speciation and extinction throughout the Earth’s history.

LO 1.21 Design a plan for collecting data to investigate the scientific claim that speciation and extinction have occurred throughout the Earth’s history.