I think sharks are amazing creatures.  How do you feel about them?
Modern sharks are known as clade Selachimorpha.
That's cool - what were non-modern sharks known as?
Sharks are a bunch of fish characterized by cartilaginous skeleton.
And they bite.....what do they eat?
"Shark" has also been used for extinct members of a subclass.
And, what do they eat?
They usually don't live in freshwater.
So, then, where do they live?
), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths of . They generally do not live in freshwater although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and freshwater. Sharks have a covering of dermal denticles that protects their skin from damage and parasites in addition to improving their fluid dynamics. They have numerous sets of replaceable teeth.
Well-known species such
Shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used for extinct members of the subclass Elasmobranchii outside the Selachimorpha, such as "Cladoselache" and "Xenacanthus", as well as other Chondrichthyes such as the holocephalid