Pocket-sized Stromatolite Fossil

stromatolite
Fossil 8cm across.
stromatolite

These stromatolites, seen in cross section in this fossil, are each just the size of a finger nail. My namesake, geologist Richard T Bell, found them in a rock formation while surveying in remote area of Canada, if I remember correctly, somewhere in the Rocky Mountains.

stromatolite
Cross section of stromatolite, 1.8 cm across

A stromatolite is a community of micro-organisms forming one layer on top of another. Colonies of cyanobacteria released oxygen into Earth’s atmosphere 3 billion years ago, leading to a mass extinction of anaerobic bacteria but, a billion years later, creating the conditions which would allow multicellular life to appear in the world’s oceans.

Stromatolites

From my wildyorkshire.co.uk blog, 19 November 2010:

THESE TINY stromatolites in a fossil from Canada, each about one inch across, were built up layer by layer on the seabed from calcium carbonate secreted by cyanobacteria, also known as blue-green algae. Once thought to be algae, they’re now grouped with the bacteria and, along with archaea, classified as prokaryotes.

Prokaryote cells have DNA but unlike eukaryotes the cells have no membrane-bound nucleus. We’re made up of eukaryote cells but our health depends on a variety of prokaryote cells – the ‘friendly bacteria’ in advertisements for Yakult fermented milk drink – that are active in our digestive systems.

Stromatolites appear right at the start of the fossil record 3,800 million years ago and they’re still with us today, in places like Shark Bay, Australia, where extreme conditions limit competition from other life forms. Stromatolites are often much larger than my pocket-sized examples – the size of a family car, for example.

Ferrybridge
Ferrybridge Power Station, 2010. As Britain achieves 50% renewable energy supply, Ferrybridge is being phased out. They blew up one of the cooling towers on 28 July 2019.
Malham Cove

Blue-green algae can be seen close to home as streaks on the cooling towers of power stations, such as Ferrybridge. The blackish streaks of blue-green algae at Malham Cove (right) gave Charles Kingsley the idea that they might have been made by a chimney sweep’s boy sliding down the face of the cliff, inspiring his story The Water Babies.

Microscopic as they are, the cyanobacteria were crucial in the story of life as they were the first organisms to use photosynthesis, releasing oxygen into the atmosphere. Cyanobacteria contain not only chlorophyll a, a green pigment, but also blue phycobilin, which combine to give the blue-green, almost blackish colour.

Link

Meeting Richard T Bell, from my wildyorkshire.co.uk diary, 30 March 2007.

Run-off

washed-out paving sand
washed-out paving sand

After a record-breaking late summer bank holiday with temperatures of 28C in Leeds, we had a downpour yesterday evening. The paving sand that I’d swept into the cracks a couple of days ago has been washed out in places by the overspill from our driveway. The dished concrete channel in front of the garage door can’t cope with the run-off from a rainstorm.

It’s been a good test for a small area. I’ll buy a small bag of cement and make a dry mix – three of sand to one of cement – with the remaining sand to brush into the crevices on the sloping driveway.

Wadi Rum

Wadi Rum, Google Earth image
The swirling shapes of my little patches of washed-out sand remind me of the run-off deposits that are left by flash floods in wadis, as in this Google Earth image from the Wadi Rum Protected Area, Jordan.

Link

Dansand No Grow Block Paving Sand: I now realise that I should have gone for the version that they do with added cement!

Tracks in the Sand

woodlice

Yesterday, after taking out a few weeds, I swept sand into the cracks between the paving slabs by the front door. Already this morning, there are signs of activity. Could these be tracks left by an insect? Or a woodlouse?

paving sand

Something has been active in the corner. I didn’t notice this tiny snail shell until I spotted in the photograph. It might have been dislodged from a crevice yesterday but I suspect that it’s been introduced along with the sand.

The sand is from Denmark. The grains are small, mostly less than a millimetre, and well-rounded, so perhaps this is windblown sand from a former dune system. Denmark has extensive dunes along its western, North Sea, coast and, further inland, extensive areas of glacial sand and gravel.

In my photograph, the glassy grains are quartz and I think that the larger, fleshy-looking ochre fragments are feldspar.

Danish sand: Dansand No Grow Block Paving Sand

Doorstep Bio-blitz

garden snail
Garden snail

The seven species that I disturbed as I weeded around the paving stones yesterday come from seven different families, four classes and three phyla, so, within inches of our front door, we have an annelid worm, a gastropod mollusc, an isopod crustacean and a social insect.

winged ant

I disturbed a large ant as I swept the driveway, which I guessed was a queen. The queen disposes of her wings after her nuptial flight, then sets about finding a suitable site – such as here under the paving stones – to start her colony.

Coincidentally, later, a few yards away, I spotted a worker ant carrying a single transparent wing, which looked like one that had been discarded by a queen.

Common NameFamily or OrderClass or SubphylumPhylum
EarthwormLumbricidaeClitellataAnnelida
Garden Snail, Helix aspersaHelicidaeGastropodaMollusca
Keelbacked SlugLimacidaeGastropodaMollusca
WoodlouseIsopodaCrustaceaMollusca
Shield BugHemipteraInsectaArthropoda
Rove BeetleStaphylinidaeInsectaArthropoda
AntFormicidaeInsectaArthropoda

Link

Dansand No Grow Block Paving Sand

Masonry Brush and Cultivator

brush and cultivator

We’ve had record temperatures for a late bank holiday so, again, I’ve been working in the shade at the front of the house, weeding the cracks between the paving slabs before cleaning up with the masonry brush and sweeping sand into the gaps with a soft brush.

I didn’t use the hand cultivator today, but it was more appealing to draw than the plastic-handled weeder that I had been using.

As I worked around the front door, I was surprised by the variety of life on our doorstep: a garden snail, woodlice, ants, small earthworms, a tiny rove beetle and one green shield bug nymph. The nymph looks like a smaller version of the adult but it lacks wings. This one had to laboriously walk over towards the cover of the hosta to escape my brushwork.

Procreate drawing

One again this is a Procreate iPad drawing and today I used just two of the available tools: the Gesinski Pen and the Round Brush.

If I’d been painting on paper, I would have used opaque gouache to add the light-coloured bristles against the darker background. This time I added them with Gesinski Pen with a 100% opaque light colour.

I was determined not to use an eraser but when I was finishing the drawing, I realised that a false start that I’d made with one of the prongs of the cultivator was throwing the whole drawing out of proportion. I opted for ‘painting’ over it in white, to produce a similar effect to when I used to correct illustrations with a dab of white gouache. The correction is intended to remain visible.

Trowel and Fork

trowel and fork

It’s too hot to do much work in the back garden but, as it’s in the shade until lunchtime, the front stays cool. I finish weeding the narrow bed below the lounge window. Welsh poppies would happily take over here but, much as I like them, we’ve got other plans.

Inevitably, as I go, I keep digging up spring bulbs. I replant all the smaller ones. The tête-à-têtes are doing well but I pick out the larger daffodil bulbs because, in this shady bed, they grow too leggy and keel over. I’ll replant them at the end of the back garden. I’ll need more than a hand fork and trowel to get to grips with the chicory and bindweed down there.

The drawing process

I drew these on my iPad using Procreate. I wanted the entire process to be visible in the finished drawing: the false starts, the construction lines and the multiple attempts to get a shape in proportion. I limited my use of the eraser. There was a detail on the trowel that I’d painted too dark, which I took back a bit with a soft, semi-transparent eraser.

As with yesterday’s view of the back garden, I used only one layer. Because of this I had to paint over my line work, so I needed to go over it again with the ‘Gesinski ink’ pen.

Published
Categorized as Drawing

Harvest Mouse

harvest mouse
The virtual ‘dry brush’ is useful for painting fur in Procreate on an iPad, and you don’t have to mistreat your prized sable watercolour brush to get the desired effect!

One of the Rodley Nature Reserve harvest mice, drawn from one of the photographs that I took there earlier this month. Hopefully this will make it into print next year in one of my Dalesman nature diaries.

Cutting Back

shed
Drawn in ProCreate on my iPad Pro
snail

Stripy brown-lipped snails hunker down on ivy leaves in our hedges. I find them even when I’m up the steps, cutting back the top branches.

We’re continuing to harvest plenty of produce from the veg beds – courgettes, potatoes, spinach, rhubarb and autumn raspberries – but we’re taking a break from beans: the french and broad beans are over but the runners, which have masses of scarlet flowers, are taking their time to burst into full flow.

One or two holly blues have been visiting the ivy, which, along with the holly, is one of the food plants of the caterpillar.

shed

Drawing on one layer in Procreate

My drawing was made in the Procreate drawing program on my iPad Pro. For a change, I’ve drawn it all on one layer. I usually keep pencil roughs, ink and colour on separate layers, which keeps the line work unblemished but that means that I’m missing out on all the efforts that the Procreate designers have put into making digital drawing feel like its real world equivalent. In this case, I don’t mind if the pen and ink gets slightly blurred as I add the colour.

Animated Shepherd

My homework for the final week of my web comics course. This little animation was produced in Adobe After Effects. I did try to add a falling snow effect too, but at least I managed to add a bit of movement.

Link

Infinite Canvas: Making and Understanding Web Comics from the Comics Studies department at the University of Dundee

Published
Categorized as Drawing

Little Westgate

Walkers
Original drawings in my pocket-sized A5 (landscape) sketchbook

It’s rare for me to sit and draw from life but I get the chance this morning as I wait for my appointment at Specsavers on Little Westgate, Wakefield. Perhaps because we’re still in the holiday season, there aren’t as many people in town as I’d expected. This is a good thing because instead of picking out a favourite character from a crowd I have to draw, at random, whoever happens to be walking past. Often there’s only one person in view.

After my course in web comics, I realise that every person embodies their own short story. Each person has a particular walk. The man with the striped trousers is the most determined and confident, while others are more diffident. The woman in the centre pauses at the threshold of a shop as if debating with herself whether she should enter.

Watercolour added later. I remember the colour of the carrier bag better than the colour of some of the footwear and trousers.

Published
Categorized as People

Goldfinch Recovery

Goldfinch

“A goldfinch has just flown into the window,” Barbara tells me, “It’s lying there on the patio, its little beak trembling.”

goldfinch

I go out, prepared for the worst. It’s a juvenile, lying on its back, wings trembling, a startled expression in its eyes and, like Barbara said, its beak opening and closing, as if it’s gasping for breath. Ringers will keep a bird calm by consigning it to the darkness of a soft drawstring cloth bag. I would usually put a stunned bird in a cardboard box to recover but I haven’t got one to hand, so I pick it up and cup it in my hands.

goldfinch

I can feel its heart thumping. It begins to perk up. I part my fingers and it does seem to be sitting up and taking notice. It has a tiny mark on its head but no other sign of injury.

I take it down to the lawn by the bird feeder and gradually open my hands. It moves onto the grass then, after a second or two, it flies off, up over the hedge . . .

. . . and right into next door’s bedroom window!

Luckily this time it doesn’t stun itself and it sits on the windowsill as it recovers.