This Realneo banner is a close up (the ribs/gills in the photo actually scale i about 4 inches long) photo of the underside “gills” of what I believe is an Oyster Fungus (pleurotus ostreatus).   The fungus grew  on a piece of firewood in Cleveland, Ohio - under a black plastic tarp which kept the fungus out of the rain.  I believe this particular fungus was growing for more than a year on  tulip tree wood. 

It is interesting that the growing morphology of the Oyster Fungus is very similar to the  coral in the upper right hand of this photo.  The coral, however, relies on the sun for its growth, where the fungus is chemosynthetic.  So – same growth form, but not for the same reason.

There are also types of coral which have the exact same “gill” structure which the underside of the Oyster fungus has.  But in coral  the “gills” face up towards the sunlight, and in the fungus the “gills” face down on the underside of the fungus cap.   Here is a photo of the lobed leather coral which shows the upwardly facing “gills”.  I have also seen (in the Caribbean) coral which have (upwardly facing) almost exactly the same radiating “gills” as the underside of this Oyster fungus, but I could not find an example in my quick search of Google images.

Is the morphological similarity of these the Oyster fungus with certain types of coral an evolutionary dna throwback?   Or just random.