Characteristics of Trichodesmium that may be relevant to its planktonic existence.

I) forms colonies which may: allow self-shading, provide a habitat for O2 consume symbionts, facilitate the creation of reduced O2 zones. ii) produces gas vacuoles which: allow modification of sinking, allow active migration and enhance the availability of dilute nutrients such as P. iii) extensive methylation of Trichodesmium DNA: modification of adenine residues, may inhibit infection, conferring stability against high UV.