Not only can Anabaena be found all over the world, it can also be found within other organisms!  Anabaena has been found within the Image from Wikipedia Commons.plant bodies of various liverworts, water ferns, cycads, and even angiosperms!  This is a mutualistic relationship, since the Anabaena gains protection from predation, and the plant gets the nitrogen that the Anabaena is able to fix in its heterocysts. 

Anabaena has been found to interact with other plants, and Image courtesy of Mike Clayton and UW-Madison Botanytypes of algae, to produce water blooms. Also, certain types have relationships with protists, and are known as cyanelles.

Finally, Anabaena has very negative relationship with some animal species.  Anabaena are toxic to many different types of animals.  Certain Anabaena species are toxic to certain animal species, however animals such as cows, pets, Image from Wikipedia Commons.wildlife, birds, and some fish are the most susceptible to Anabaena poisoning, through drinking infected water.

Now that you know so much about Anabaena take a look at the references page for more sources of information, and a little bit about the author, or you can always go back home.