Aymz's: All About Sharks

Today we have a huge debate about sharks having eggs and whether it is a fish or a mammal at our lunch break. I claimed that Sharks DO lay eggs and they are NOT mammals, but the others thoughts contradicts mine's. I think that all fish with fins swish their fins left to right (including sharks), where as all mammals with fins swish their fins up and down. another point i pointed out was that sharks have gills! just like fishes do! unlike whales, dolphins and seals who doesn't have them. Another reason on why I thought that sharks are fish is because the have to swin continuously to breath. they do not surface for oxygen like those other finned mammals do. Also, they lay eggs! but my friends said that they do not. they said that sharks give birth and is a mammal...

...and so, i did a little research and guess what, I'm right! :D
... and for the egg part, we're both right! Some sharks give birth while some lay eggs XD

here's a little proof...

What is a Shark?

Sharks are a type of fish.

Sharks are amazing fish that have been around since long before the dinosaurs existed. They live in waters all over the world, in every ocean, and even in some rivers and lakes.

Unlike bony fish, sharks have no bones; their skeleton is made of cartilage, which is a tough, fibrous substance, not nearly as hard as bone. Sharks also have no swim bladder (unlike bony fish).

source: http://www.enchantedlearning.com/subjects/sharks/

SHARK BABIES

Baby sharks are called pups. Just like there are many types of sharks, there are also different ways that sharks come into this world. There are three ways that sharks are born:

eggs are laid (like birds)
eggs hatch inside the mother and then are born
pups sharks grow inside the mother (like humans)

Sharks can have from 1 to 100 babies at a time, depending on the type of shark. The ones with pups that grow inside the mother have fewer babies at a time than sharks that lay eggs outside the body.

Sharks do not care for their babies after they are born, but they do search for a safe place where they can lay their eggs or give birth.

source: http://www.kidzone.ws/sharks/facts7.htm

Some pics of shark eggs...