Slime Mold

By: EV Staff

Imagine taking a Bay Area winter hike and seeing this:

Photo by: Kelly Graham (“eggs”)
Photo by: Kelly Graham (“dog vomit”)

What you’re looking at are unrelated eukaryotic organisms informally called Slime Mold, a brainless, single-celled organism. There are over 900 species of slime mold and come in a variety of colors and shapes like honeycomb, eggs (see photo) and even, “dog vomit”. (see photo).

EV, Kelly Graham visited Hellyer Park and Arastradero Preserve recently and came across several slime molds in the leaf litter under and on trees. While they look like a fungus and share a similar habitat, they are actually considered amoebozoans. Though that classification has met challenges and our knowledge of this group seems to be ever shifting. In a Bay Nature article in 2018, author Angela Pi received questions about Slime Molds that we find very interesting. 

Slime mold organisms feed on bacteria, algae, and fungal spores. They are frequently found on decaying bark, leaf litter, or even living tree bark like those shown in Kelly’s photos. They are amazingly SMART and according to a PBS article can smell food, pulsate their way to food, can devise the best route to their meals, re-form if they get torn apart, and Kelly shared her observation that “these social ameba seem to aggregate to move toward higher ground in order to disperse their spores.” All of us at EV were surprised and delighted.


Curious to learn even more? Check out this article from Smithsonian Magazine about How Slime Mold stores memories.