snails
All animals help the ecosystem such as the spider kills bugs so they don't over populate. Also, the cat kills the mice, the bird eats the worm, and a lot more!
it helps balance out the way of life in an ecosystem.
it depends on what animals you are talking about.
Dr. Brian Fisher on the Secret Life of Ants
How Seafood Watch Project Protects the Ocean
How Company Alumni Help Alma Mater Firms Succeed
Global Warming in Chilean Patagonia