Geeking Science: Symbiosis

Red Saxifrage in Sardinia (look at the other rocks round the flowers for lichen)
Image courtesy of Phil_Bird at

Toby Spribille asked a question and went down a rabbit hole. “How closely related are two lichen growing in the same area that look like they have the same structure, but one is yellow and acidy-poison and the other a benign brown?” Obviously different species, since color and acid difference, but when did they split off of each other?

Except he found out he asked the wrong question. The question should have been “How do three separate DNA species create a symbolic relationship and within that relationship, sometimes they create acid?”

Because lichen were involved, everything got turned on its head.

Lichen has been doing that for a while.

In 1868, Simon Schwendener discovered lichen were composite organisms – fungus who had co-opted and shared life with some alga. (Fond, How a Guy…) Not a happy idea in a time where Darwin’s On the Origin of Species – only the strong survive – ruled. Why would two creatures need each other to survive? That’s just nonsense.

Other scientists tested Schwendener’s findings under the microscope. “You know, he isn’t wrong.” More testing and the concept of symbiosis was born in biology.

Humanity has since gone on and discovered nearly everything on this planet has some internal helpful flora and fauna hanging out. For example, the human microbiome in the digestive system from the stomach through both the small and large intestines is helpful, and gets really upset when antibiotics take out the good bacteria. (There is some debate about whether eating yogurt helps – the two major bacteria in yogurt get killed in the stomach acid long before arriving in the large intestines to help replace what modern medicine erased.)

Symbiosis has became the name of the game. And raises lots of questions for science fiction authors about if humanity goes to the stars, how long will them remain human when other planets start affecting the colonists microbiomes. 

Now lichen are rewriting things again. Instead of the clear structure of the fungus protecting the alga, there is a third party involved – at least proven by DNA testing in 2016 and reverified in 2019 through a second scientist for the same basic community of lichen.

Other scientists are looking into other lichen, and discovering similar things there. Previously the other fungus were ignored, because lichen were defined as a partnership of two – now, polyamory seems to be the rule for lichen.

That is another thing writers and editors should bring to the table when writing, and we often forget. Science isn’t about doing something wild and crazy in a one-off. It’s about a running tests over and over, building up knowledge. Testing already known information with new equipment. And, most important, peer review.

In genres with laser focus on a character or group of characters – like urban fantasy and science fiction, the network community of science is often downplayed.

But, like lichen, it takes more than one scientist to thrive.

Read more about the lichen discoveries below in the Bibliography.


Grens, Kerry. Not One, Not Two, But Three Fungi Present in Lichen. The Scientist. 2019 January 17.–not-two–but-three-fungi-present-in-lichen-65333 – last viewed 11/12/2019.

Yong, Ed. How a Guy From a Montana Trailer Park Overturned 150 Years of Biology. The Atlantic. 2016 July 21. – last viewed 11/12/2019.

Yong, Ed. The Overlooked Organisms The Keep Challenging Our Assumptions About Life. The Atlantic. 2019 January 17. – Last viewed 11/12/2019.