What is the total number of living species?
According to chapter 1 of the Global Biodiversity Outlook 1 of The Convention on Biological Diversity, 2007-05-19 (http://www.cbd.int/gbo1/chap-01.shtml), the approximate number of described species is 1.74 million, and the estimate total of existing species, 14 million. These estimates are inevitably incomplete, because new species will have been described since publication of any checklist and more are continually being described; most groups of organisms lack a list of species and numbers are even more approximate.
There are currently about 1.4 million identified animal species, and about 1 million of them are insects. Biologists estimate the number of animal species could be as many as 5 million. The total of living plant and animal species is estimated as 8.7 million species. This does not include bacteria which could number in the hundreds of millions of species and subspecies.
We currently know of approximately 1.6 million species, with the number growing every year. We only know of a very small percentage, however, with estimates of the total number of species numbering 7-100 million. Because of the human impact on the environment, however, many of these species may die out before we ever find them.
Why does the total number of chromosomes have to remain constant between members of the same species?
During his travels, it was revealed to him that an enormous number of species inhabit the Earth. He noticed that every place he went to had different animals that were suited for that environment. However, similar environments didn't always have similar species. There could be immense variations of the same species all over the world. zzz