Bouncy Blubber

Introduction

For years, it was thought that the only use for blubber was to keep dolphins and other marine mammals warm in chilly water. But researchers now believe that this fat may be energy-saving in a whole new way.

Podcast

Bouncy Blubber

Transcript

How blubber gives dolphins extra bounce. I'm Bob Hirshon and this is Science Update.

Few animals can match the grace and power of a speeding dolphin. Recently, researchers found that dolphins owe some of that remarkable speed to their layer of blubber.

Ann Pabst is a functional morphologist at the University of North Carolina, at Wilmington. She found that blubber is more than just a layer of fat cells.

Pabst:
When we looked at blubber more carefully, we realized, yeah, there was a lot of fat in that tissue, but boy it was also a highly organized connective tissue structure.

In fact, she and her colleagues found that the blubber between a dolphin's top dorsal fin and its tail flukes is crosshatched with elastic fibers. And in the same way that high-tech athletic shoes help basketball players speed down the court, this blubber puts more spring into the dolphin's strokes.

Pabst:
The animal is kind of bouncing on a blubber spring through its marine environment. And in so doing, decreasing the amount of metabolic energy that they have to use to swim.

The research is helping scientists better understand how dolphins can swim so quickly and effortlessly. And it's even being looked at by makers of boats and submarines, to see if they can make a propeller that works as well as the tail of a dolphin.

For the American Association for the Advancement of Science, I'm Bob Hirshon.

Making Sense of the Research

Why study a dolphin's blubber? While it may look like one continuous sheet, blubber is very specifically built for different functions on different parts of the animal. Studying these different structures and functions helps us understand how animals deal with the same physical principles and laws that cars, boats, planes, and people do. An interesting follow up to this story would be to look at some of the human technologies that have been guided by the work of biomechanists and functional morphologists. For example, what sports technologies have been modeled after the structure of animals? How about cars, boats, and planes—has morphology helped inform the design of these technologies?

Now try to answer the following questions:

1. What are the different functions of a dolphin's blubber?
2. What was the key that led researchers to believe that the dolphin's ability to swim at high speeds could be related to its blubber?
3. What are the implications of this finding for humans?
4. Can you think of examples of human technologies that resemble the structure of an animal?

Going Further

For more information on thermoregulation, read Animal Adaptations for an Aquatic Environment from Sea World/Busch Gardens. Extensive information on dolphins is also available at this site.

Blubber is designed to streamline a dolphin's body in a precise way, as well as to provide thermoregulation and buoyancy control. Compare this to the new swimsuits that debuted at the Sidney 2000 Olympics. Are there any structural similarities? What advantage was this suit designed to give swimmers? What marine mammal served as the model for the suit? Visit Speedo's FastSkin Fact Sheet to learn about the development of the new suit. Then, go to If the suit fits...Technology vs. athleticism at heart of bodysuit debate from the CNN/Sports Illustrated site to read about the controversy surrounding the suit. What do you think? Do these suits give swimmers an unfair advantage?

For a 6-8 lesson that explores how technology has been used to enhance human abilities, go to the Science NetLinks lesson entitled Extending Human Ability through Technology.