Find the sweet spots in the fossil record

Many kids like to imagine they are paleontologists. It's a great adventure to hunt for and find precious fossils from when the dinosaurs ruled the Earth. Studying fossils, however, is hard work! Paleontologists endure weeks-or even years-of painstaking work in all kinds of weather to study life on Earth during prehistoric times.

Invite your kids to practice their paleontology field techniques with this "cookie excavation" activity, developed by the educators at Badlands National Park.

Here’s what you need

- Cookies (one of each type for each child): hard chocolate chip, chewy chocolate chip, hard oatmeal raisin, soft oatmeal raisin

- Paper towels

- Toothpicks

Here’s what you do

Place a paper towel at each child's place at the table. On each paper towel, place one hard chocolate chip cookie and one hard oatmeal raisin cookie. In addition, give each child six toothpicks.

Ask each child to use a toothpick to try to excavate the chocolate chips out of his or her cookie. If the toothpick breaks, chips, or becomes dull, they must discard it.

After 3-5 minutes, check on their progress. Was anyone successful in extracting a chip or raisin from the cookie? What condition were the chips or raisins in that were excavated? Did any chips or raisins come out clean, or were bits of cookie clinging to the sides? Was it easier to extract chips or raisins? Why?

Now try the same process with the soft cookies. The same rules apply-if the toothpick breaks, throw it away.

After 3-5 minutes, check in with them again. Is it easier or harder to excavate chips from this kind of material? Which cookie do your kids think most closely resembles an actual fossil dig environment? Why?

Fact

The Gobi Desert in central Asia is one of the most active excavation sites on Earth. Conditions there are just right for fossil preservation; it has yielded some of the world's most exquisitely preserved fossils, like the Mamenchisaurus, (above) a creature with the longest neck of any known animal.

See Mamenchisaurus and other ancient Gobi-dwellers in the Science Museum of Minnesota's giant Chinasaurs: The Great Dinosaurs of China exhibit, November 10, 2004 through May 1, 2005. For more information, visit www.smm.org or call 651-221-9444.