12 November 2024

Many of us go to Homewood Cemetery to see birds like this merlin in December 2020, but there are many other attractions and some of them are subtle. Did you know the cemetery is a good place to find lichens?

Lichens are two organisms that operate as one, a symbiotic partnership of a fungus with a green or blue-green algae, sometimes all three.  The algae’s photosynthesis feeds the fungus.  The fungus gathers water and nutrients and protects the algae. This combination allows lichens to thrive in some of the harshest places the planet but they are sensitive to air pollution.  Those that grow on trees and tombstones are totally dependent on the surrounding air and precipitation for their nutrition.  Ultimately their tissues absorb elements in concentrations that mimic what’s in the air.

Since lichens are indicators of air quality, it was natural that GASP (the Group Against Smog Pollution) would hold a lichen walk at Homewood Cemetery on 2 November led by GASP’s Laura Kuster and cemetery historian Jennie Benford.

We didn’t have to walk far to find lichens.

They look like rumpled leaves stuck to the headstone. The leaves are reaching into the air.

The lichen’s shape gives an indication of local air quality.

• Flat lichens (Crustose) have the least air exposure and can survive in relatively bad air.
• Those that look like crumpled leaves (Foliose) can survive in medium air quality — not good but not bad air. We saw a lot of these at Homewood Cemetery.
• Shaggy lichens that drip in open bunches (Fruticose) have the highest air exposure and need really good air quality to survive. We did not see any of these at Homewood Cemetery.

Next time you’re at Homewood Cemetery check out the lichens. When you find the Howard Irish tombstone you’ve hit the jackpot!

21 October 2024

Thornless roses are the rose fancier’s dream but are difficult to breed, are usually infertile, and require a genetic mutation to block the prickles from emerging on the skin. Because the underlying trigger is still present, new growth on a “thornless” rose can produce prickles at the drop of a hat — injury, root suckers, etc.

What we call “thorns” on roses are technically prickles because they grow out of the skin. Roses, wineberry and devil’s walking stick have the same gene coding for prickles.

What are the genes underlying prickle development? Two studies published in August 2024 investigated Solanum prickle plants (eggplants, tomatoes) and found that they share the same LOG family genes. When scientists disrupted those genes it resulted in prickle loss in multiple species and did not adversely affect other parts of the plant.

Because roses have prickles and may share the same gene coding, there is new hope for creating a truly smooth stemmed rose.

See a summary of the studies in Smithsonian magazine. The two scientific studies are here and here.

p.s. Why are rose thorns actually prickles? Find out at Ohio State University: Armed by Nature: Thorns, Spines, and Prickles

20 October 2024

This week the Good News Network reported on a study published in ScienceDirect that shows fungi perceive shapes in the world around them, have memories, make decisions and solve problems. All without a brain!

A Japanese study of fungal networks set up an experiment with wood cubes pre-colonized with a wood decaying fungus, Phanerochaete velutina. The fruiting body and mycelia are shown below.

The scientists laid the cubes on a bed of clean soil in two patterns, a circle and an X, then observed and photographed what happened over a period of months.

• By Day 13 the fungi had grown filaments (hypha) that made the cubes look fuzzy, particularly in the X shape. (hypha are collectively called mycelia)
• By Day 34 some filaments from each cube had joined with the mycelia of neighboring cubes, but the rest of the hyphae were still seeking so the shapes were super fuzzy.
• By Day 116, almost four months later, the “chatter” had subsided and the fuzzies were mostly gone in favor of strong, efficient networks.

Over time it became obvious that the fungi were not acting randomly. They remembered shapes and were making decisions.

If the fungi didn’t display decision-making skills, they would simply spread out from a central point without consideration for the position of the blocks.

For the X arrangement, the degree of mycelial colonization was greater in the outermost four blocks. It was hypothesized that this was because the outermost blocks can serve as “outposts” for the mycelial network to embark on foraging expeditions, therefore more dense connections were required compared to the five blocks inside the X.

In the circle arrangement, the degree of mycelial colonization was the same at any given block. However, all the empty space inside the circle remained clear. It was proposed that the mycelial network did not see a benefit in overextending itself in an already well-populated area.

— Good News Network: Scientist Shows Fungi Are ‘Mind-blowing’: They Have Memories, Learn Shapes, Can Make Decisions and Solve Problems

In order to optimize their patterns the fungi must be communicating through the network. That’s where the beautiful split gill mushroom (Schizophyllum commune), shown at top, comes in.

Two years ago a study of electrical signals in the filaments (hypha) of enoki, split gill, ghost and caterpillar fungi discovered that their signals pulse when there’s something important to say such as “Found a new source of food.” Sometimes the pulses were similar to words and it appeared that the fungi knew 50 “words.”(*)

Read more about the “word” study at Good News Network: Research Suggests Mushrooms Talk to Each Other With a Vocabulary of 50 ‘Words’(*) See the source publication at Royal Society of Open Science: Language of fungi derived from their electrical spiking activity.

(*)NOTE: Some skepticism was reported at the end of the Good News Network “words” article:

Some scientists are skeptical that the research was done looking for ‘language’, suggesting that this puts a shroud of exaggeration and overexcitement about the findings.

To his credit, Adamatzky explained to the Guardian that it could be simply that the electrically-charged tips of hyphae were just creating electromagnetic reactions as they explore the forest underground.

— Research Suggests Mushrooms Talk to Each Other With a Vocabulary of 50 ‘Words’