There are thought to be about 9 million different species on Earth, not counting bacteria. Out of all these species, almost 85 percent on land and about 90 percent of those in the water have yet to be discovered or described. Out of the five kingdoms of species counted in the estimate, Animalia has the most species, with more than 7.8 million species projected. The smallest kingdom is Chromista, which includes algae and other basic cells, with only about 100,000 projected species. Of these, less than half have been cataloged.
More facts about species:
- If bacteria were counted in the number of species on Earth, it would be dramatically higher. Although estimates of the number of species of bacteria vary widely, even the most conservative are in the 10 million range. That would mean that the number of species on Earth would more than double.
- There are more than 611,000 species of fungi alone, fewer than 15 percent of which have been described and cataloged.
- If the 9 million species estimate is correct, even the most sophisticated endangered species list reviews only about 1 percent of all species.
