This single criteria helps placing the animal species in one of the two groups, the vertebrates and the invertebrates animals. So before a scientist or a zoologist begins to learn about the animal, he or she first decides, whether it comes under vertebrates or invertebrates animals. We will learn about the vertebrates and invertebrates differences by individually understanding the characteristics of each group.

Difference Between Vertebrates and Invertebrates

The following information on animals will help you understand the differences between each group.

Which Animals are Known as Invertebrates?
Invertebrates are animals that belong to a large animal group. These animals do not belong to a single sub-phylum like the vertebrates. The invertebrates are those animals without a backbone. Invertebrates are multicellular organisms and mostly form a colony of individual cell that function as one. All the cells in the colony have a particular function. They have no cell walls and many have tissues, except the sponges. Most of the invertebrates produce sexually.

Most of the invertebrates can move except the adult sponges. There are many invertebrates that follow symmetrical organization. This means one can draw a line down the middle of the animal and the two sides will be similar like mirror images. Invertebrates are heterotrophs that feed on plants and animals. The invertebrates include the following animals:
Phylum Porifera - Sponges
Phylum Cnidaria - Jellyfish, hydras, sea anemones, corals
Phylum Ctenophora - Comb jellies
Phylum Platyhelminthes - Flatworms
Phylum Mollusca - Molluscs
Phylum Arthropoda - Arthropods
Phylum Annelida - Segmented worms like earthworm
Phylum Echinodermata - Echinoderms
Which Animals are Known as Vertebrates?The vertebrates are grouped under sub-phylum Vertebrata. The vertebrates are animals that possess an internal skeleton, that is, endoskeleton. This endoskeleton is made up of an internal column of vertebrae. The sub phylum Vertebrata is grouped within the phylum Chordata. The vertebrates form the most advanced organisms on the planet. Vertebrates are larger than the invertebrates. Most of the vertebrates have an advanced nervous system, that makes them smarter. The other characteristics of vertebrates include a bilateral symmetry, body segmentation, complete digestive system, closed blood system, bony or cartilaginous endoskeleton, tail and ventral heart. The animals of the vertebrates group include:
Fish
Amphibians
Reptiles
Birds
Mammals
Marsupials
Primates