Relative age and relative dating
Here is an easy-to understand analogy for your students: relative age dating is like saying that your grandfather is older than you.
Absolute age dating is like saying you are 15 years old and your grandfather is 77 years old.
Geologists establish the age of rocks in two ways: numerical dating and relative dating.
Numerical dating determines the actual ages of rocks through the study of radioactive decay.
Throughout the history of life, different organisms have appeared, flourished and become extinct.