Puzzles

Here are a range of interesting puzzles to try:

   Baleen or toothed whale? 

    Dolphin body parts - mix and match, wordsearch

    Dolphin dilemma

    How many cetacean?

    Turtle puzzle

    Whale food wordsearch

    Here are even more puzzles:

Which dorsal fin belongs to whom?

The dorsal fins of these cetaceans are all mixed up! Can you help these poor animals find their dorsal fin?

1. Bottlenose Dolphin

A.

2. Killer Whale

B.

3. Humpback Whale

C.

4. Harbour Porpoise

D.

Answers:

1C, 2A, 3D,4B

Whales, dolphins, porpoises and their dorsal fins

You have just learned what the dorsal fins of the Bottlenose Dolphin, the Killer Whale, the Humpback Whale and the Harbour Porpoise look like. Some whales, dolphins and porpoises have very big dorsal fins, while some of them have very small ones. The location and shape of the dorsal fin varies as well. For example, look at the difference between the dorsal fin of the Killer Whale and the Humpback Whale. The fin of the Killer Whale is very big and is located in the middle of its back, while the dorsal fin of the Humpback Whale is quite small and is located further to its tail.

And did you know that some have no dorsal fin at all! On the pictures you can see a Finless Porpoise, and a Northern Right Whale Dolphin.

Because the dorsal fins of all the whale, dolphin and porpoise species look different, it is possible to identify what kind of whale, dolphin or porpoise it is. The shape of the dorsal fin can even be used to identify individual animals.

Figure 3: Dorsal Fins of the Bottlenose Dolphin

By looking at the dorsal fin, researchers can identify which dolphin is which, because each dorsal fin looks different. On the picture above you can see a scar in the dorsal fin of the dolphin. Because of this, a researcher can identify this dolphin very easily.

Evolution in a labyrinth

Can you answer this question below?

With what other mammal does the dolphin share a common ancestor?

Walk through the labyrinth, beginning at the starting point, and pick up the letters you find on the shortest path to the finish. This will give you the answer to the question above.

From land mammal to dolphin

About 55 million years ago the ancestors of sea mammals, like whales, dolphins and porpoises, evolved from land mammals. You can see that dolphins evolved from land mammals by looking at their bone structure. On the picture below you see the skeleton of a dolphin.

You can see that by looking at their pectoral fins; they have a complete hand structure with five finger bones, just like we have!

Whales, dolphins and porpoises have a heart, kidneys and intestines just like you. Like humans, they also nurse their young. The mammary glands and the nipples are inside mammary slits. When the calf nuzzles the mother dolphin, the nipples protrude, so the calf can drink.

Have you ever noticed that whales, dolphins and porpoises move their tail up and down, instead of from right to left like fish do? The reason they do that is because they evolved from land mammals. During evolution land mammals have developed strong bones and muscles to support themselves against the constant downward pull of gravity. Their ‘up-and-down’ muscles are therefore very strong. Therefore, when land mammals evolved in sea mammals, like whales, dolphins and porpoises, they started to swim around by moving their tail up and down.