Studying stromatolites

■ Hi HIW,

I have read with interest the feature on page 15 in issue 131 of How It Works. The feature by Mindy Weisberger is interesting, but what she doesn’t mention is the fact that there are some rare living remains of stromatolites which survive to this day. They are most accessible at Sharks Bay on the northwest coast of Australia, and less so at a remote coral cay in the Bahamas.

As Mindy would probably be aware, as part of their photosynthesising process the cyanobacteria, which together form the rock-like stromatolites, give off minute quantities of oxygen. With their