on this walk I led on Sat 8 Sept for Plantlife ..
so surely that justifies a write up here on this blog!
Only four people were able to come. I dedicate this post to the several other people who did not make it.
Click for Other Posts about Lichens on this blog
Algae and Lichens Walk
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| Looking at Nostoc in front of Malham Yorkshire Dales National Park Centre |
We start by looking at "Blue-Greens"..
(also known as Blue-green Algae, Blue-Green Bacteria or Cyanobacteria)
We start by looking at Nostoc in front of the Malham Yorkshire Dales National Park Centre
Nostoc is a Blue-green growing in the spaces between the limestone cobbles.
When dry it looks like black dried up sheep droppings, or dried tar.
When wet it looks like dark black-green jelly.. or ... black wet sheep droppings.
And everyone except us (the Algae group) ignores it.
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| Piece of Nostoc on hand. |
There was no life ..
No oxygen.
Only gases such as methane.
4.2 billion years ago organisms similar to Blue-Greens formed in the sea.
They have tiny cells (5µ long) and the genetic material is mixed up in the cell.
(Most "modern cells", of organisms known as "Eukaryotes" which includes everything from sea-weeds to fungi, worms to humans, have the genetic material in the nucleus separated from the rest of the cytoplasm of the cell by a membrane)
These Blue-greens lived there for 2 billion years
- 2 billion years
- nearly half the life of our planet.
Nothing but Blue-greens. (Well almost)
They began to produce oxygen.
And after 2 billion years
there was enough oxygen in the atmosphere
for other plants as we know them to begin to evolve
We owe a lot to blue-greens. "Come out and join us and see the Nostoc!" I say to the information man at the National Park Centre.
He comes -- but
Oh dear!
They have weeded and cleaned the cobbles.
"Two weeks ago" he says
Never mind. There is bound to be some left.
And there is!!.
"Crachats de lune" - Spittle of the moon
"Crachats de diable" - Spittle of the devil.
Named as such in France because it appears to fall from the sky overnight..
We have no English name for it..
Last week I was in the Netherlands at a conference of ECEN. We held a meditation, showing the History of the Universe.. by making a spiral and the candles showed when events happened.The Universe is 13.75 billion years old.
Just think .. it took 9.25 billion years until the earth formed..
and then there was 2 billion years whilst the blue-greens worked away eventually producing oxygen.. till other life could evolve.
The Blue-green period lasted 1/7 th the age of the Universe.
.. How I wish those people at ECEN could be with us on this sunny day in Yorkshire looking at Nostoc..
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Nostoc grows in chains of cells. Occasionally a larger cell is seen in the chain called a Heterocyst. These cells are special because the can fix atmospheric nitrogen to make nitrate fertilizer.
Nostoc occurs in several lichens. A lichen is an association of an alga (which can photosynthesise and capture the suns energy and make sugars) and a fungus (which cannot make its own sugars - but which gives the lichen structure and which can collect nutrients from the substtatum) -
It occurs in Jelly Lichens (Collema) - which we found in several places.
It occurs in black streaks on the cliffs at Malham Cove and Gordale Scar -
resembling the soot left by Tom the Water-Baby as he scrambled down a cliff..
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| Rivularia "buttons" 5cm across, in the foreground in Gordale Beck |
I could tell you long tales about the other Blue-greens we saw -
Gloeocapsa on the millstone grit capstone of the church wall,
Ossilatoria which can "swim" (will wriggle/float) to the surface of puddles
Rivularia which makes little buttons on pebbles in shallow lime rich streams
but there isn't time.
I could tell you long tales of the birds we saw:
Spotted fly catcher flitting out of the tree and back
Green wood pecker yaffling as its green back shot from the field down to the wood
Sparrow hawk searching for prey
Raven/Buzzard high above Gordale waterfall
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| Grey Dagger Moth Caterpillar - Acronicta psi - will overwinter as pupa |
I could tell you tales of the butterflies we saw
Peacock
Small tortoiseshell
Grey Dagger-moth caterpillar
I could tell you tales of the Grass-like plants we saw
Festulilium-loliacium
Festuca arundinacea
Eleocharis palustris
Bromopsis.. could it possibly be benekenii?
Typha latifolia
I could tell you tales of the geology we saw
The Mid Craven Fault, Limestone, Shale, Reef Knolls, Tufa, Travertine.
The transformation and joy as a teenage Pakistani dressed girl, in best longish pretty dress, black trousers, flat canvas shoes and headscarf carefully tiptoed up the boulders in the stream, holding up her skirt, following her two younger brothers..... then abandoned keeping her feet dry and ran in the stream laughing... later photographed by her father using (a sign of 2012.. an Ipad/small tablet.
The friendly chat with local artist Katharine Holmes
Our own enjoyment at stall at the Gordale Bridge as we sat on green chairs in the sun and dappled tree shade eating ice-cream and local beef sandwiches
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| Learning about the different types of lichens growing on the National Park table |
And I could tell you tales of the 20 or so lichens we saw. and how we learned about the different types of lichen - crustose, leprose etc..
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| Haematococcus pluviatilis |
- but that will all have to wait for another time...
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| Trentepohlia an orange coloured filamentous alga |
or better come out on a walk with us!
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| Pointing to the Cladophora glomerata in Gordale Beck |
On the way home I drove through a corner of Plantlife Nature Reserve of Winskill Stones and took a quick photo. Thank you to my Plantlife friends who accompanied me today.. If you had not come, the walk would not have taken place..
Click for Other Posts about Lichens on this blog
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