Overview
By acting as pairs of penguin "parents" and "babies," children will explore how animals use scent to communicate.

Estimated Time and Age Level
Preparation: 30 minutes the night before
Activity: One 45-minute session
(Ages 6-12)

Materials
Five strongly scented, non-toxic liquids such as vanilla, peppermint, oil of cloves, vinegar, and almond extract (oil-based extracts work best and can be obtained at a lotion store or the local grocery)

Assuming a group size of 30:
15 cotton balls

15 small plastic 35mm film containers with lids

Permanent marker and masking tape (to make labels)

Preparation
Contact a local store that develops film or ask a photographer to save film containers with lids. You will need half as many as the total number in your group or class.

At least one day before the activity, prepare three identical containers with each of the five scents in the following way: Wet three cotton balls with one scented liquid. Place each cotton ball inside a film container. Seal container with lid. Label the lids and container bottoms with obscure codes such as "V" on the bottom and "L" on the lid for vanilla. (Make the container and lid codes different from each other so children can't match them visually.) To transfer the scent on the cotton ball to the lid, store upside down overnight. Repeat these steps for each scented liquid.

Just before conducting the activity, shake the containers one last time.

Remove the lids and place in one location. Place the container bottoms in a separate but nearby location.

Be sure to have the same number of lids laid out as containers. The total should equal your group size.

Procedure
Explain that the population of a penguin rookery (nesting site) can number well into the thousands. The noise is deafening. How could a lost chick find its parents in such a crowd? Humans recognize each other by sight and sometimes by sound. What about smell?

Divide the group into two sets. Give each person in one of the sets one of the 15 scent container bottoms. These individuals will be the penguin "parents." Give each individual in the second set a scent container lid. These individuals will be penguin "babies."

Have the penguin babies gather and mill about in the center of the room. The penguin parents (returning, theoretically, from foraging for food) then must find their own penguin baby with the same scent. Remind the penguin parents to keep their containers right-side-up so the cotton ball does not fall out.

Give the parents five minutes to move around and match scents. If the scents match, baby and parent should sit down.

At the end of the activity, determine how many babies survived by checking whether the codes on the container's lid and bottom match. Ask: How well did everyone "communicate"? Was anyone unsure about a scent or did scents overlap? If you practiced this activity a couple of times, would the group produce more successful matches? Collect the scent containers and store them for a future session, if you like.

Assessment
Ask children to design an experiment to test communication by scent or odor. How long do odors last? Do some travel farther than others? How quickly and how far do odors travel? (They might try this classic experiment: open a bottle of ammonia at the front of a room, and have individuals raise hands as the scent reaches them.)

Extension
Besides keeping family ties, scents help animals communicate in other ways. For example, ants lay down an odor trail between a food source and the nest so that others can find their way. Many animals urinate at strategic points to define the border of their own territory.

Using scented film canisters and working in two group's, set up an "odor trail" outdoors. One scent, such as vanilla, can mean "You're on the right track." Another scent, such as vinegar, can mean "Wrong way" or "Predator!" Each group can then try to follow and map out the other group's trail.

This activity has been copied, with permission, from the National Science Foundation server to ours, to allow faster access from our Web site. We encourage you to explore the original site.