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Mediterranean On the Rocks:
The Sea Within the Sea

Life in the waters of the Mediterranean Sea is especially perilous for its native finback whales and bluefin tuna. A new marine reserve in the Ligurian Sea, plus ongoing projects to track and analyze whales and tuna here, will help these and other species of marine wildlife survive the challenges of this unique ecosystem.

Curriculum Links
National Science Education Standards
Discussion: Sounds of Whales
Activity 1: Whale Songs
Activity 2: Make a Paper Whale



fish, marine mammals





(Please visit the Subject-Area Search feature on this website for related Frontiers shows and activities!)


5-8: Structure & Function in Living Systems; Reproduction & Heredity; Populations & Ecosystems; Diversity & Adaptations of Organisms
9-12: The Cell; Molecular Basis of Heredity; Biological Evolution; Interdependence of Organisms; Matter; Energy & Organization in Living Systems; Behavior of Organisms
5-8, 9-12: Understandings About Science & Technology
5-8: Populations; Resources & Environments; Natural Hazards; Science & Technology in Society
9-12: Population Growth; Natural Resources; Environmental Quality; Science & Technology in Local, National & Global Challenges


Whales living in different pods, or groups, communicate using distinct calls or dialects. Scientists researching whale communication have found that, with at least some whale species, each pod of whales has its own dialect or speech pattern that can be used to distinguish its members from whales of other pods. As dialects are passed from generation to generation, minor changes occur. Observations show that dialects of pods recently split apart are more similar than dialects of pods separated for many years.

Humpback whales have been studied and recorded extensively. Their songs have a structure and pattern made of sound building blocks. The most basic component is called a unit, which is a single sound like a click, moan or whistle. Several units sung in sequence make up a phrase (click-click-whistle-moan, for example). A theme is com-posed of several distinct phrases sung in sequence. Some whales, like orcas (killer whales), communicate through simple sounds, while other species, like the humpback, can sing complex songs lasting up to 30 minutes.

In this story, scientists study the finback whales living in the Ligurian Sea. This group of whales has maintained its isolation and its dialect over time and does not mate with whales in other groups. While finback whales from other parts of the world migrate, sometimes traveling very long distances, the finbacks in the Ligurian Sea appear to be unique in that they stay in the Ligurian during winter.



Biologists who study animal communication often find it helpful to study a visual representation, or voiceprint, of an organism's sounds. By converting sounds to a drawn tracing, it is easier to analyze and compare unfamiliar noises like clicks, moans and groans. The drawings below represent tracings of sounds made by five different killer whales. Study these tracings, and then answer the questions that follow.

  1. How many pods do you think are represented? Explain.
  2. Which whales are from the same pods? Explain.
  3. Which whales are from the most distant pods? Explain.
(Please see below for the answers.)


Examine the sequence of tracings pictured below. Then, on a piece of paper, write down the letters to indicate the sequence that best represents how a pod's sound might change as it is passed down from generation to generation (Sequence= __ - __ - __ - __).

(Please see below for the answers.)


  1. Locate the Ligurian Sea and other sites mentioned in this episode on a map.

  2. Research the migration routes of the finback whale and bluefin tuna and plot them on a map.

  3. Investigate other species of whales, their current status (endangered or not), population, research into their communication.

  4. Killer whales (orcas) can be heard on the radio in Vancouver, B.C. Listen to the orcas at

  5. Find examples of American dialects and accents. Listen to the speech of people in and from other regions. Differences in pronunciations of common words (route, roof, wash, car, park, creek) will provide clues to a person's native accent. Think about how differences in human speech might keep groups isolated. Investigate and map U.S. dialect regions. See for more.


Part 1
  1. 3 pods
  2. pod 1 = A and D; pod 2 = B; pod 3 = C and E
  3. pods 2 and 3 are the most different
Part 2

Sequence: The sequence that makes the most sense is C-B-D-A or the reverse, but students may be able to support other sequences.


Origami is a great way to learn about and practice principles of math and geometry. Writer and educator Barbara Pearl has turned the ancient art of origami into a series of workshops that teach mathematical and geometrical concepts. Pearl developed origami for the classroom and published her activities and teaching techniques in a book, Math in Motion: Origami in the Classroom.

Some of the mathematical concepts that can be learned by doing origami include spatial skills, symmetry, angles, fractions and ratios, problem-solving and more. Activities in Pearl's book support NCTM standards.

Now you can make your own whale.


  • origami paper (pre-cut paper works best because it is the right size and shape and is precisely cut, but you can certainly prepare your own and recycle paper at the same time)


  1. Place a 6-inch square sheet of paper on the table so it looks like a diamond (refer to graphic below).

  2. Fold the right point over to meet the left point (fold in half). Unfold. Find the center crease (line of symmetry).

  3. Fold the lower right and left sides to meet at the center crease (line of symmetry). (The paper should look like a kite at this stage.)

  4. Fold the apex (top point) down to the base line to form a small triangle.

  5. Fold the right side over to meet the left side.

  6. Put your finger on the bottom as you turn the whale sideways.

  7. Fold the end point up to make a tail.

  8. Draw a happy face (if you wish). Have a whale of a day!

Adapted with permission from Math in Motion: Origami in the Classroom K-8 by Barbara Pearl.


  1. Create origami figures for other kinds of whales like the finback seen in this episode. Design origami patterns for fish and other marine mammals.

  2. If you are in Philadelphia, Pa., visit the Math in Motion origami exhibit at the Franklin Institute of Science.

  3. Some other sites about paperfolding and using origami in the classroom include: and Visit the MIM website for more, including links to other math and origami sites:

For free teaching suggestions, send a self-addressed, stamped envelope with two first-class stamps to: MIM, P.O. Box 567, Langhorne, PA 19067. Request "25 Ways to Use Origami in the Classroom."


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