Background Information 

Review the following video, “What Happens When Continents Collide.” The video summarizes the Great American Biotic Interchange (GABI). This was an important late Cenozoic paleogeographic and biotic event in which land and freshwater fauna migrated from North America via Central America to South America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor and bridged the formerly separated continents. 

The Paleobiology Database

In this lab exercise, you will be introduced to a new online tool that uses real data of fossil occurrences around the world and across geologic time called the Paleobiology Database. This is a tool that scientists use to locate the occurrence of fossils of any taxa that has been found anywhere in the world. The interface for this tool, the Navigator, is quite user friendly. Open the Paleobiology Database Navigator here: PBDB (Links to an external site.). 

Instructions

In the first part of this exercise, you are going to look at the migration of several terrestrial animals including Machairodontinae or “Saber-toothed tigers”, and Glyptodontoidea, related to modern armadillos, Later in the exercise we’ll add data for Canidae (dogs) and Megatheriinae (giant ground sloths!).  In this activity, you will be constructing distribution maps using the PBDB Navigator for each of these animals during the Oligocene, Miocene, Pliocene, and Pleistocene epochs of geologic time. This covers the geologic time period during which the North and South American continents joined together at the Isthmus of Panama. The Cenozoic geologic time Era with the epochs appears below:

Steps:

1. Download the maps that you will need to complete this exercise: Maps Download Maps
2. You may choose to complete the map annotations by hand or use simple drawing tools in Word. (Watch the video tutorial to see how simple it is to use these tools).
3. Type (write) your name on each map.

Machairodontinae

1. Return to the PBDB Navigator (Links to an external site.) and in the upper right search bar, enter: Machairodontinae. A “Taxa” drop down menu will appear; select Machairodontinae.
2. Use the geologic time scale at the bottom of the screen to filter the fossils by epoch. Double click on “Cenozoic” on the geologic time scale and then select Oligocene. This will filter the data to only show the distribution of Machairodontinae from the Oligocene epoch. 
   1. Review the data on the Navigator map focusing on North and South America.
   2. Return to your blank Oligocene map and open the drawing tools in the Word document.
   3. Annotate the Machairodontinae distribution for the Oligocene epoch. (In Word, select Draw from the toolbar, then “Draw,” your pen type, and a color from the drop down menu. Watch the Lab Video Tutorial if you need more help.
   4. Annotate the Key in the upper right of each map with the color that you used for the distribution of Machairodontinae.
   5. Repeat this for Machairodontinae distribution on each map for the Miocene, Pliocene, and Pleistocene epochs.  
   6. Use the same color for the Machairodontinae on all four maps.

Glyptodontidae

1. Return to the PBDB Navigator and clear your filters (bottom left of map).
2. Follow the same steps above for Glyptodontoidea. Use a different color to represent Glyptodontoidea on each of your maps; add that color to your key.

Completing the rest of the lab exercise

1. Analyze your completed maps and move on to the Quiz portion of this exercise to answer questions here: Module 07 – Lab #1 Questions – The Great American Biotic Interchange.
2. You will be updating these maps with additional critter distributions.