Scientists have never had a good handle on exactly how many species of plants, animals, and fungi there are on Earth. Estimates have ranged from 3 to 100 million species. However, a new study, published in PLoS Biology, has yielded a much more accurate (we hope) idea of how many different types of living organisms are on our planet. Scientists now believe that about 8.7 million species live on Earth, an estimate that’s accurate, give or take 1.3 million.
“The question of how many species exist has intrigued scientists for centuries and the answer, coupled with research by others into species’ distribution and abundance, is particularly important now because a host of human activities and influences are accelerating the rate of extinctions,” said lead author Camilo Mora of the University of Hawaii (via TG Daily).
Here’s the breakdown of the 8.7 million species:
- 6.5 million live on land
- 2.2 million live in the ocean
- 7.77 million are animals (we’ve cataloged 953,434 of these)
- 298,000 are plants (we’ve cataloged 215,644 of these)
- 611,000 are fungi (we’ve cataloged 43,271 of these)
- 36,400 are protozoa (we’ve cataloged 8,118 of these)
- 27,500 are chromista (we’ve cataloged 13,033 of these)
A few more facts:
- 86 percent of land species have yet to be discovered
- 91 percent of ocean species have yet to be discovered
- Only 1.25 million species have been registered
- 700,000 more species have been described, but not officially identified
At our current rate of discovery, it could take 1,200 years of work by 300,000 taxonomists to catalog all of the species on Earth. And by the time we’re done, who knows how many of them will still be alive.
“Many species may vanish before we even know of their existence, of their unique niche and function in ecosystems, and of their potential contribution to improved human well-being,” said Mora.