Over 95% of living organisms on the planet earth are marine invertebrates. Marine Invertebrates are organisms that lack a notochord, or backbone, and live in saltwater environments. Accounting for over 50,000 of Earths species, marine invertebrates can be found in almost every marine habitat on the face of the earth. Fossil records suggest that there have been Invertebrates living on earth for at least 665 million years. Invertebrates are animals that consume other organisms to produce energy and have a stomach type organ to aid in this process.