TM TEACHER’S GUIDE “Sometimes I dream I’m swimming along, alone, when I hear dolphins near me, and I understand what they’re saying to each other… I can understand their language. It’s farfetched, I know… What can I say?… That’s my dream.” —Dr. Kathleen Dudzinski MACGILLIVRAY FREEMAN’S TM An Educational Resource for Teachers The large format film, DOLPHINS, is appropriate for all intermediate grades (4-8). This Teacher’s Guide will be most useful when accompanying the film, but is a valuable resource on its own. Teachers are strongly encouraged to adapt activities included in this guide to meet the specific needs of the grades they teach and their students. All activities developed for this guide support National Education Standards for Science, Geography, Math and English, but are not referenced in this guide due to space constraints and differences in standard use throughout the nation. Introduction Table of Contents Dolphins —Animals We Are Science Still Trying To Figure Out On Location 1 Introduction Humans cherish and admire beings who possess The MacGillivray Freeman noble traits. The resourcefulness, confidence and Films crew filmed scientists at 5 ACTIVITY 1 Literacy Sandwich, grace of dolphins endear them to our hearts and work for DOLPHINS. It’s not Hold the Mayo minds. It is because we search for the same easy to follow wild dolphins characteristics in ourselves that we cherish these and study them, but Drs. 6 ACTIVITY 2 Deep Diving! magnificent animals. Kathleen Dudzinski and We like to think that dolphins enjoy being Alejandro Acevedo-Gutierrez 8 ACTIVITY 3 Save the Dolphins! around us as much as we do them. Is it possible are doing exactly that. To that dolphins share our company simply for diversity? study at close range, the 10 ACTIVITY 4 What’s the Chatter? Some species can become bored with their own researchers must wait for dol- kind. Who gets more out of the relationship: the phins to come to them, not a 12 ACTIVITY 5 Hidden Identities! human or dolphin? They provide us with insight simple task since dolphin into the realms of anatomy, behavior and commu- groups can travel up to 50 14 ACTIVITY 6 Feeling a Little nication. Still, our curiosity pushes us to learn more. miles per day. Off Balance? Although we admire other animals, dolphins Dudzinski’s research remain high on our list of species that fascinate us. focuses on behavior and com- ACTIVITY 7 Scientists believe that marine mammals are munication. She spent nearly 16 Listen and Learn descendants of animals that once lived on land. The 2,000 hours in the Bahamas skeleton of a dolphin supports this theory. There is gathering data amounting to 18 ACTIVITY 8 The Eyes Have It! a modified form of hands in the front flippers of a only twenty hours of usable dolphin. Two small, unattached bones located recordings. Like Dudzinski, 20 ACTIVITY 9 Uncommon Sense! behind the rib cage are believed to be remains of Acevedo earned his doctorate the pelvic girdle, to which hind limbs once attached. from Texas A&M. He special- 22 ACTIVITY 10 Talk The Talk Most people wouldn’t know it, but dolphins have izes in behavioral ecology of a common ancestor with hoofed animals, specifi- marine mammals and has 24 Resources, cally cows. With so many cow lovers out there as researched dolphin feeding Acknowledgements well, it wouldn’t be a surprise. behavior and foraging techniques. Adding to the challenge of finding dolphins “To the dolphin alone, beyond all is the inconvenience of carrying the technical other, nature has granted what the equipment. With more bulk and weight than the ® best philosophers seek: friendship average movie camera, the 92-pound IMAX filming unit is not easy to carry in or out of water. Because for no advantage.” of its bulk, it had to be placed in an underwater —Plutarch, Greek housing for easier maneuvering and was given the TEACHER GUIDE moralist and biographer nickname “Miss Piggy”by the film crew. 1 for tourists, marine mammals included. The spirit of the people, appealing climate and warm waters make it a pleasing choice for a vacation. The middle of the Bermuda Triangle, appropri- ately named Hope Town, was the starting point for the crew. Many fish inhabit this archipelago. It’s no coincidence that dolphins spend a lot of time in this area. Known for its calm, warm and clear waters, the Bahamas provide dolphins shelter from tropical storms. The MacGillivray Freeman Films crew filmed Dean Bernal swimming with a bottlenose dolphin named Jojo off the coast of the Turks and Caicos Islands. Off the southern coast of Argentina, Puerto Piramides is battered by a cold, windy ocean. Despite the challenging conditions, this is a key feeding site for dusky dolphins. Anatomically Correct Thanks to her invention of a 25-pound mobile video/acoustic array, Dudzinski had an The dolphins’use easier time moving than the film crew. The array of echolocation was the key component in deciphering which dol- sets them apart phin was making noise. On land, there is a slight from most ocean delay in sound that allows us to interpret the dwellers. Dolphins direction of its origin. Since sound moves 4.5 use echolocation to times faster underwater, the delay is less, making detect food under it more difficult to find the source. With a group of sand and maneu- dolphins all making noises at the same time, this ver through dark could be a big dilemma. The array records dolphin or cloudy water. A vocalizations with two underwater microphones, dolphin can find a called hydrophones. They are set on a bar at least single BB (shot) 4.5 times the distance between Dudzinski’s ears. when dropped at the far end of a 70-foot (21 m) During the analysis of the videotapes, the delay pool in less than 20 seconds. There is also a theory produced by that distance allowed her to localize that they can focus sound into a narrow beam that the sound source. Combining the hydrophones projects out in front of them. The direction of the and a high-tech video camera in a waterproof beam is selected by them. shelter allowed her to tape the dolphins visually Dolphins also rely on their eyes for survival. while recording their vocalizations. The unit also To rest, they close an eye allowing one side of their contains a smaller box. The box contains a Digital brain to sleep, while the other eye patrols the Audio Tape (DAT) recorder and filter with a third water for danger. Staying in a group also makes it hydrophone attached—the click detector. This easier to rest. recorded the signal envelope of dolphin echoloca- Their eyes help them adjust to their surround- tion clicks. Echolocation involves sending out a ings by opening wide to see in dim light and nearly stream of pulses called a click. The echo sounds closing to see in bright sunlight. When they jump are received by the lower jaw of dolphins. From above the surface, dusky dolphins can see up to there, the sounds are transmitted to the inner ear five miles. Also, each eye moves independently of via the middle ear. Without this detector, the pitch the other, enabling it to follow different objects at of the clicks is too high for humans to hear. Despite the extra effort required to carry them, the click once. Finally, there is the ability of the eyes to see detector and array earned their keep by supplying directly forward or backward. This is an invaluable new (or never before recorded) information on how tool in helping spot food or detecting an dolphins use sounds and behavior to communicate. approaching enemy. All mammals breathe air. Dolphins, unlike most Locations: Places of Contrast mammals, exchange 80 percent of lung volume with each breath. In comparison, we only use 20 In the film, dolphins can be seen swimming in percent with each breath. They also have flexible bodies of water all over the world. Still, like most rib cages that prevent their bones from breaking on animals, dolphins have their preferred homes. Two deep dives. They can dive up to 1,640 feet (500 m). TEACHER GUIDE of these are the Bahamas and Patagonia, Argentina. They can stay under water for more than eight 2 The Bahamas are a popular vacation destination minutes. Stored oxygen is used for diving, while the efficiency of their lungs allows them to con- serve heat and stay under longer. Most humans can spend no more than one minute under water. These unique mammals provide us with valuable scientific knowledge. Understanding their built-in sonar and its capacity to detect size, shape, texture and density of underwater objects could help in furthering sonar development. The shape of a dolphin’s body and its capability to reach great speeds (21 miles per hour or 33.8 km) might assist design of sea vessels. They can achieve these great speeds by bowriding a fast moving vessel. This allows them to surf pressure waves while expending Keeping distance and avoiding pursuit of dol- no energy. We can look at the way dolphins swim to phins is vital for their safety and ours. assist us in building quicker boats, much like birds have helped us design better aircraft. Random Acts of Kindness When a member of a group gets injured, two More Aggressive Than We Realize dolphins may swim underneath and support it When most people think of dolphins, they think of below the flippers, then bring it up to the surface Flipper from television and film.