1. By: Luka Prpa

2. What is a shark? Sharks are skillful predators, but only a few of them are dangerous to people. Sharks range in size from about 6.5 inches long to 40 feet long. All sharks belong to one class of fish called Chondrichthyes - have bones made of cartilage. Sharks go through a thousand teeth in a lifetime - as old teeth break or fall out, new ones replace them. Sharks are covered in small teeth-like denticles which make their skin very rough. Sharks mainly live in the sea but sometimes come inland. Strategy: Digging for Meaning

3. Shark Attacks Sharks do not purposely attack people. Shark attacks are usually mistakes. Sharks mistake humans for their usuall prey. Each year 50 to 75 people are attacked, but only 5 to 10 attacks end in a death. Most shark attacks occur during summer months. Attacks usually happen from 2:00 PM to 6:00 PM. Attacks are most likely to happen in less than 6ft 6in of calm water and about 35ft away from shore. Strategy: Four Quadrants

4. Why do people kill sharks? People kill sharks for all sorts of reasons. Some of those reasons are for sharks' meat, fins, skin, and liver oil. People also kill sharks for pure sport. The biggest threat to sharks is overfishing worldwide. Sharks that get caught in fishing nets often get thrown back into the ocean dead. Sharks are even killed in nets to protect swimmers. I think sharks should not be killed to protect swimmers - people should just stay away from places where sharks will attack. Strategy: Making Connections

5. Sharks in Fresh Water Most sharks are usually found in the sea. There is one shark that can live in fresh water. This shark is called the Zambezi river shark (picture on right). The shark has a unique body which allows it to adjust to big changes in salt water. Zambezi River Shark

6. Shark Growth Sharks can grow up to 40 feet long. Sharks can also grow as small as 6.5 inches long. The whale shark is the biggest shark and the dogshark is the smallest. Half of the 375 species of shark grow smaller than 3.3 feet long. Whale Shark Dogshark

7. Study of Sharks It is hard for scientists to study sharks in the wild because they constantly move and swim too fast. Sharks also dive too deep for divers to keep up with them. Scientists study and follow sharks by catching them and attaching a sonic tag - a radar to keep track of the sharks - to their fins (this is called tagging a shark). When the sharks are released, scientists keep track of them by picking up radio signals with a receiver. I think scientists should just catch sharks, study them in a pool of salt water, and then release them. sonic tag on a shark fin Strategy: Making Connections

8. Shark Senses Strategy: Determine Importance One reason that sharks are such good predators is because they have great senses. Two-thirds of a shark's brain is dedicated to its best sense - smell. Sharks have a mirror-like layer in eyes which helps them see better in water. Sharks have an extra sense than humans, sharks can feel the vibrations of their prey in the water.

9. Fun Facts Strategy: Digging for Meaning Some pacific ocean islands used to worship sharks as gods. Shark skin has been used to smoothly sand marble finishes, as well as wood/timber finishes. Sharks kept in captivity grow 10 times faster than in the wild. A tiger shark's teeth are strong enough to crunch through a turtle's shell and bones. shark in captivity tiger shark teeth

10. Shark Families Sharks Hunting in a Group Strategy: Making Connections Sharks don't really live in families. Sometimes sharks hunt in groups but that is the closest to a family. When sharks give birth or lay an egg, they don't care for their babies. I think most sea animals don't care for their babies. Sharks just find safe places to lay their eggs or give birth.

11. Sources Maynard, Christopher. Informania Sharks. Cambridge, Massachusetts: Candlewick Press "Physical Characteristics of Sharks." Wikipedia. http://en.wikipedia.org/wiki/Shark http://en.wikipedia.org/wiki/Shark "Sharks." Shark Facts. http://www.kidzone.ws/sharks/facts.htmhttp://www.kidzone.ws/sharks/facts.htm MacQuitty, Miranda. Shark. New York: Alfred A. Knopf

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