Does anyone know the estimated number of species on the planet?

Answer 1

As a soft guide, however, the numbers of currently identified species can be broken down as follows:

287,655 plants, including:
15,000 mosses,
13,025 ferns,
980 gymnosperms,
199,350 dicotyledons,
59,300 monocotyledons;
74,000-120,000 fungi;
10,000 lichens;
1,250,000 animals, including:
1,190,200 invertebrates:
950,000 insects,
70,000 molluscs,
40,000 crustaceans,
130,200 others;
58,808 vertebrates:
29,300 fish,
5,743 amphibians,
8,240 reptiles,
9,934 birds,
5,416 mammals.
However the total number of species for some phyla may be much higher:

5-10 million bacteria;
1.5 million fungi;


from wiki.

Answer 2

Between 2.5 million and 5 million are known and categorised and probably about that same number remain to be discovered. And in the next month and for every month after that at least one of those species will become extinct. More species have gone extinct than currently exist on the planet.

Answer 3

Species are the fundamental unit of biodiversity, but, of all the tens of millions of species that have existed on the earth, only a comparatively small percentage have been studied in detail. Some species have been well studied, such as many large mammal, butterfly, bird, plant, and insect species. But very little is known about the biology and distribution of vast numbers of species groups such as arthropods, fungi, and nematodes. In the past decade, scientists have discovered species in areas that were previously inaccessible, such as the tube worms in deep sea thermal vents and discovered new species even in relatively well populated areas.

There have been a number of efforts to estimate the number of species that are known and have been described. This is a challenging job because there are no central registries for species, and no one database. Often species that have been described by scientists in one geographical site, are also recorded and described by scientists at another. It takes time and research for biologists to recognize these redundancies. In addition, scientists have different opinions about what constitutes a species or a subspecies. Biologists define a species as a population that interbreeds under natural conditions. However, there are ambiguities in this definition that add to the difficulty of enumerating species, even those that have already been discovered.

The United Nations Environment Programme's Global Biodiversity Assessment is often cited, which estimates the number of described species at approximately 1.75 million. One study done by prominent biologist E.O. Wilson and others estimate known species at approximately 1.4 million, while another study
estimates the number at approximately 1.5 million.

There are also differences in how organisms are categorized. For example, for many discoveries, scientists must determine whether is it a species or a subspecies. It is an easier task to classify mammals and plants, but consider the difficulties of classifying bacteria. Very few bacteria species have been given a scientific name. One Norwegian study found between 4000 and 5000 bacterial species in a single gram of soil. A single square meter of "tropical grasslands can hold 32 million nematodes. Biodiversity is not evenly distributed across species or across regions. Over half of all described species are insects, including approximately 300,000 known beetles, a fact which led biologist J. B. S. Haldane to remark that God has "an inordinate fondness for beetles."

Considering the difficulties in assessing the number of species already known, imagine the difficulties of estimating the total number of species on the planet. Coumpounding the problem is the fact that diversity is not evenly distributed across the planet. Seventy percent of the world's species occur in only 12 countries: Australia, Brazil, China, Columbia, Ecuador, India, Indonesia, Madagascar, Mexico, Peru, and Zaire. The tropical rain forests are believed to contain more than half the number of species on Earth.

Answer 4

milions and increasing...every year scientists discover some new species..the most of them are insects..insects are the most numerous on our planet..

Answer 5

Billions & then there's me,