How many animals ara there in the world?

The exact number of animal species in the world is not known, as new species are being discovered regularly. However, it is estimated that there are between 5 and 50 million species of animals on Earth. This number includes both vertebrates (animals with backbones) and invertebrates (animals without backbones).

The majority of animal species are invertebrates. Insects are the most diverse group of animals, with over 1 million known species. Other major groups of invertebrates include arachnids (spiders, scorpions, and ticks), crustaceans (crabs, shrimp, and lobsters), and mollusks (snails, clams, and octopuses).

Vertebrates are a smaller group of animals, but they include some of the most familiar animals, such as mammals, birds, reptiles, amphibians, and fish. There are about 60,000 known species of mammals, 10,000 species of birds, 10,000 species of reptiles, 6,000 species of amphibians, and 30,000 species of fish.

The number of animal species is constantly changing. New species are being discovered all the time, while others are becoming extinct. It is estimated that about 1,000 species of animals become extinct each year.