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Online Lessons for Teachers: Learning Evolution


How Did Humans Evolve?

Back to LESSON 5

Activity 1: Teacher Notes

Activity 2: A Tree Full of Ancestors

Activity 2: Teacher Notes

Activity 1: Fossil Finding

You are a paleoanthropologist working at a dig site in Africa. You spend months in quest of fossils. You walk, squat, and investigate pieces of broken fossils. Unfortunately most bones belong to baboons and hyenas. So you walk and squat and look again. Then one night, you head back to camp, and something catches your eye. Another monkey femur, right? But it's not. You've never seen anything exactly like it before. And there are more fossils with it.


What is it?


When did it live?


What did it look like alive?


How did it move?

Check out the evidence from four different digs to see how scientists unlock the secrets of fossil remains. Fossils are evidence of species that lived long ago, most of which are now extinct. By studying their structure, scientists can fill in family trees and determine how organisms were related. This helps show how one species evolved from another and how species can be traced back to a common ancestor.

You will try to answer the questions above about famous fossil finds:


The remains of Lucy, the first Australopithecus afarensis find, discovered in Hadar, Ethiopia in 1974 by a team of fossil hunters including Don Johanson;


The skull of a mature male A. afarensis found in 1992 in the Hadar region of Ethiopia (Hadar Skull) by a team led by Yoel Rak and Bill Kimbel;


The Laetoli Footprints discovered by Mary Leakey in Laetoli, Tanzania in 1978;


Don Johanson's "First Family," a group of 13 individuals of different ages and sexes found in Hadar, Ethiopia in 1975.


Print out these instructions, and let's get to the dig sites.


Your teacher may assign you to a small team of researchers. Choose a dig site, or your teacher may assign one to your group.


Launch the Riddle of the Bones Web activity. Answer the four questions above, or divide them among your teammates. Your task is to use the evidence at your site to answer the questions. You may concentrate on your own question but share information with your team. (You may need to investigate the fossil evidence from the other sites in order to compare it to your evidence.)

 Screen grab from the Web activity Riddle of the Bones.

Riddle of the Bones


Remember your objective. Use the fossil evidence to answer your question and then share your research with other team members. Don't forget to write a summary of your group's findings.


If you want to review fossils and dating methods, you should visit The Record of Time Web site. If you want to learn how scientists determine the age of fossil finds select "Learn More" on the When Did They Live? page in Riddle of the Bones.


Finally, you will discuss the relationship between the organisms found at your site and those found at other sites. Discuss this with your whole class.


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