A partnership with benefits
Defying everything we know about how living things obtain nutrients and energy, this lichen attaches itself to rocks. Its survival in this fashion may be a testament to the strength of partnerships and the importance of sharing.
Rock tripe is a lichen, which is actually three or four organisms living together in one structure: a fungus, a photobiont (either an algae or a cyanobacteria), and often yeasts as well. The photobiont gathers sunlight and converts this to sugars, which are shared with the fungus. The fungus in turn provides the lichen’s structure, including its anchor to the rock it calls home. Associations with yeasts serve to enhance this multi-party, mini-ecosystem.
These ecosystems harbor intricate biological and biogeochemical processes. Some scientists view lichens as having combat zones, composed of algal slaves and fungal exploiters, which are also characterized as niche seekers or take-over specialists. Others tend to see them as sharing resources and services for the good of the greater community.
Rock tripe’s shape and smooth outer surface bears a resemblance to tripe, or cow’s stomach. And like the cow’s stomach, rock tripe can be eaten, but is generally considered to be survival fare. It can be useful for thickening a soup but otherwise does not have much culinary value.
These rocks were photographed in Coastal Rivers’ Doyle Preserve. To see them for yourself, and enjoy a lovely view of Pemaquid Pond, CLICK HERE for more info and directions.