Most marine species 'will be discovered this century'

As many as two thirds of the species living in our oceans may still be unknown to science, say researchers, despite the fact that their calculations indicate that there are many fewer species than previously thought.

Stranded whales identified as world's rarest type

The world's rarest whale has been seen for the first time, after a mother and her male calf were stranded and died on a New Zealand beach.