https://www.youtube.com/watch?v=8bczZ727OSk
Animals range in size from no more than a few cells to organisms weighing many tons, such as the giant squid. By far most species of animals are insects, with groups such as mollusks, crustaceans, and nematodes also being especially diverse. … All animals are members of the Kingdom Animalia, also called Metazoa.
There are many living things in the world. To keep them simple and easier to remember, the scientists had identify many groups of animals. The six main groups are: invertebrates, mammals, birds, amphibians, reptiles and fish
Vertebrate animals can be categorized into 5 main groups: Mammals, birds, fish, amphibians, and reptiles. The following are examples of vertebrate animals, some of them given by their generic names; when we say “deer”, we mean that all the species of deer are vertebrates, for instance.
First, we don’t even know how many types of animals there are in the world, let alone how many individual animals there are. Scientists have recently estimated that there are approximately 8.7 million species on Earth. They believe that 1-2 million of those species are animals.
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