Vertebrates have a back bone. They have living endoskeleton, pharnyx and efficient respiration, advanced nervous system, and paried limbs.
Fish, eels, and lobsters living in coral reef not reed are examples for habitat.
There's been a lot of bad news for polar bears recently. In 2007, for example, scientists reported that if global warming continues unabated, the population could drop two-thirds by 2050.
