Why are 97% of all animal species invertebrates?

The reason is most likely that the word 'invertebrate' applies to a very wide variety of animals. If we look at the taxonomical hierarchy, we can see that all 'vertebrates' are in the phylum chordata. read more

The reason is most likely that the word ‘invertebrate’ applies to a very wide variety of animals. If we look at the taxonomical hierarchy, we can see that all ‘vertebrates’ are in the phylum chordata. read more

To group all invertebrates together is an immodest proposal, since the definition of "invertebrate" is any animal without a spinal column — no less than 97 percent of all animal species on Earth. read more

Quick Answer. Invertebrates make up between 95 and 97 percent of all animal species on Earth. They play a number of hugely important roles in their ecosystems, such as food, pollination and decomposition. read more