Invertebrate

An invertebrate (in contrast to a vertebrate), is an animal with no spine.[1]

Most living animals are invertebrates, including arthropods, molluscs, and annelids.

The phyla contained in Invertebrata are:

* Protozoa \- Mostly simple, single-celled organisms
* Porifera \- Sponges
* Coelenterata \- Hydra, jellyfish, anemones and corals
* Echinoderma \- Starfish, sea urchins and sea cucumbers
* Annelida \- Worms
* Brachiopoda \- Bivalves, such as mussels and clams
* Polyzoa \- Single celled critters that usually form colonies
* Mullusca \- Whelks, ammonites, cuttlefish, squids, snails, etc.
* Arthropoda \- Crustaceans, insects, arachnids, trilobites, etc.[2]

## References[edit]

1. ↑ Wile, Dr. Jay L. Exploring Creation With Biology. Apologia Educational Ministries, Inc. 1998
2. ↑ Invertebrate Paleontology, Henry Woods, Cambridge University Press, 8th Edition (1946)