Magic Microbial Spheres

Bacterial sphere with a few cyanobacteria
The bacterial spheres attract cyanobacteria in a magic way. The latter appear to recognize them from some distance, and creep towards them in a well directed movement. Finally they penetrate into a sphere and attach to the membrane from inside. The cyanobacteria belong to the genus Phormidium. Sometimes diatoms of the genus Navicula are included within the spheres. They appear to feel good and grow within the sphere to high densities.

 <        ^        >