Ecology

Cyanobacteria are prokaryotic, plant-like organisms that have been around for three to four billion years. They are incapable of sexual reproduction. However, like eukaryotes, which are generally more sophisticated organisms, they thrive on sunlight and release oxygen. Cyanobacteria were perhaps the first oxygenators of the planet. Certainly they played a paramount role. However, it is important to note that there are far more effective natural oxygenators of the water supply, such as true algae.
We dislike cyanobacteria for several reasons:

1. They make our lakes look bad. “Pea soup” green cyanobacteria blooms are ugly.
2. They are a poor base for aquatic food chains.
3. They are relatively poor oxygenators.
4. Many species produce odorous metabolites that give water an undesirable taste and odor.
5. Many species produce toxic compounds.

Eukaryotes

Prokaryotes