Baby sharks shed teeth in the womb:

A SHARK sheds teeth throughout its life, continually replacing them with new
ones. Researchers have now found that this tooth replacement starts before
birth.

       Two researchers named 
Michael Gottfried , Malcolm Francis studied a pregnant female great white shark,
Carcharadon carcharias, that had been caught by fishermen.

Teeth are vital to marine predators, and that  whites has evolved a
particularly dangerous set. To keep its dental arsenal in peak condition, the
great white doesn't wait for teeth to wear. 

                But the researchers were surprised to find that, many baby shark's teeth began to grow while they are in the mothers womb.Many of these teeth were tiny, conical and unserrated, very

different from those of adult great whites.

Sharks’ teeth have

different shapes, depending on where they are in the jaw. 

Last but not the least , they fight among themselves and  whoever can survive in this fight will  born.