What is the difference between a chimaera and a shark?
The chimaera is comparable to the shark, but it has a bit of pores and skin protecting its gill slits called an operculum, whereas sharks do not. Most chimaeras have a poison-filled backbone in front of their dorsal fins. The top jaws of chimaeras are fused to their skulls, while those of sharks are not. Sharks have replaceable teeth, however chimaeras have permanent enamel plates. Chimaeras always hatch from eggs. The female chimaera lays large eggs in a leathery egg case, and the case lies at the bottom of the ocean for anywhere between six months and one 12 months before the eggs hatch. Some sharks lay eggs and others give birth to live young. Sharks can lay up to 100 eggs, while those that give delivery to live young have one or two young at a time.
