Its called a stromatolite (stro’-mat-o-lite). It’s a fossil remnant of mats of cyanobacteria, also known as blue-green algae. The microorganisms grew in mats, bound together by slimy secretions that allowed entry of nutrients but protected them from environmental hazards.
This allowed them to form three dimensional “microbe cities” that took knobby shapes. The top image shows the irregular outer surface of this small stromatolite. The middle image shows the interior with its wavy, layered appearance. The lower, microscopic images show structures within this mat.
Earth originally had very little atmospheric oxygen and nearly all organisms were “anaerobic.” The cyanobacteria seriously altered earth’s environment by releasing “toxic” oxygen into earth’s atmosphere which endangered the simple anaerobic life but made it possible for complex forms of “aerobic” life to develop. For better or for worse, these organisms made our existence possible; I’m glad they did.
#stromatolites #cyanobacteria #oxygen
Eskildoodle Photos and Feelings 