Suppose you ask your friend for a drink, and you're thinking that you want water because you are really, really thirsty. Then your friend brings you a glass and you take a big gulp and almost choke on it. What happened? He thought you wanted a soda. Maybe you should have looked at it and smelled it before you took that drink! Has something like that ever happened to you?
Eye to Eye
When you compare the eye of a shark to that of a human, you find that they are very similar in a lot of ways. Like your eyes, a shark's eyes have irises, pupils, and lenses.
Would you know what was in each teaspoon if you had a teaspoon of sugar and a teaspoon of salt in front of you? How could you and your friends tell one from the other?
If you take the wrappers off different kinds of gum, can your friends guess which one is peppermint and which one is spearmint? In each of these examples, you need to rely on your senses of sight and smell before you use your sense of taste to figure out what kind of food is in front of you.
Do Sharks Have Ears?
You can't see a shark's ears because they are located down inside of the shark's head. Even though you can't see these inner ears, the shark has excellent hearing and balance because of them.
Did You Hear That?
Sharks have many ways to find their food, and they usually are pretty reliable. Scientists believe that the first thing that gets a shark's attention is noise. Sound waves travel really well through water from distances that might be as far as a mile away.
Speaking of sound waves, have you ever blown a dog whistle? A dog hears the high-pitched sound, even though you can't. Sharks hear sounds that are too low for us to hear. Once they hear them, they immediately start to search for whatever made that noise, knowing that it usually means food.
Because I am so beautiful, most people think that they would like to touch me. But beware! I can actually sting you with a touch. Do you know which one I am?
Think of all the sounds that you connect with lunch or supper: sizzling meat in a skillet, the ringing of the timer from a microwave, the noise of a mixer or a blender, or the snap that a toaster makes right before it pops up your bread. What other sounds can you think of that make you think of food?
Talk about a great sense of smell! Scientists believe that a shark can detect blood in the water from farther away than the length of a football field. Once the shark smells blood, it will start swimming in that direction. Although a shark seems to have a nose like ours, it doesn't have to worry about getting water up its nose or choking, like we do, because the holes in its nose are not very deep. These holes or nostrils are like open bags that allow the water to pass into them and then out again. This way the shark can sample the water and swim towards the strongest smell.
This bull shark is looking for dinner. Figure out his path by matching the scenes in the small boxes with the big picture.