The answer to this question is quite difficult. However, the number varies within 1,250,000, which are identified. Of these, 1,190,200 constitute the invertebrates, while the rest 58,800 forms the vertebrates.
There are approximately about 5416 mammalian species, 5743 amphibians, 8240 reptiles, 9800 avian species, and 29,300 species of fishes under the vertebrates. The invertebrates are organisms without a vertebral column and form the insects, crustaceans, such as crabs and lobsters and mollusks. These broad classifications are further categorized into sub-heads and classes in accordance with the similarities and differences exhibited by the species. Scientists claim that there can be more than 30 million species of unidentified insects in the rainforests. Carl Linnaeus is credited with recording of the species. He recorded more than 18,000 species on his ventures.
Biodiversity and Counting
Keeping a count of the species revolves around biodiversity. It gives an idea to zoologists and scientists about how the composition of species changes or overcomes change through times and let them examine the factors that affect the count of species.
Factors Affecting Counting
Even with the increase in technologies for maintaining statistical data, counting species always takes a hit because of certain factors. Counting the species is difficult when it comes to varied habitats. For example, organisms that are known to dwell in the soil and other difficult terrains are hard to quantify. Likewise, smaller is the species, the difficult it becomes to keep a note of their number. Another factor that plays an important role in distracting the count is the mass extinction of some species, which may have been brought about by catastrophes, such as the woolly mammoth and rhinoceros and the saber- tooth tigers.
Purpose of Counting
With greater danger of extinction of rare species, it is of vital importance to maintain a detailed record of the animal species. This helps in spreading knowledge about their conservation and preservation.
