Have you seen this?
http://www.bbc.co.uk/newsround/27541177 (http://www.bbc.co.uk/newsround/27541177)
Interesting, specially the fact that there has been approx. 18,000 new species found in the last 12 months :shock:
I think I once read that there are approx 4 million species identified to date and an estimate that there are "probably" about 10-13 million altogether. Millions left to identify in the oceans and in the soils. It also said that you should wait a long time before saying something is extinct because years later it quite often is discovered again !!