Invertebrate Poetry

Photo One by © Nevit Dilmen / CC BY-SA (
Pond-skater (Photo One)

Dear Readers, when I woke up at 5 a.m., as I sometimes do, I found myself thinking about poetry, and about how often invertebrates are used to stand in for all kinds of human attributes and experiences. I adore W.B Yeats, as much for the way that the lyricism of his work begs to be read out loud as anything – think of ‘An Irish Airman Foresees His Death‘ or the most misquoted poem of the Twentieth Century, ‘The Second Coming‘. But you might not be quite so familiar with this, ‘Long-Legged Fly’. Three perfect visual images, linked by the idea of the fly. Actually, a pond skater is not a fly, but I forgive him.

Long-Legged Fly

That civilisation may not sink,
Its great battle lost,
Quiet the dog, tether the pony
To a distant post;
Our master Caesar is in the tent
Where the maps are spread,
His eyes fixed upon nothing,
A hand under his head.
Like a long-legged fly upon the stream
His mind moves upon silence.

That the topless towers be burnt
And men recall that face,
Move most gently if move you must
In this lonely place.
She thinks, part woman, three parts a child,
That nobody looks; her feet
Practise a tinker shuffle
Picked up on a street.
Like a long-legged fly upon the stream
His mind moves upon silence.

That girls at puberty may find
The first Adam in their thought,
Shut the door of the Pope’s chapel,
Keep those children out.
There on that scaffolding reclines
Michael Angelo.
With no more sound than the mice make
His hand moves to and fro.
Like a long-legged fly upon the stream
His mind moves upon silence.

And how about this, from Fleur Adcock, who lives in East Finchley. I love the way that this poem starts from a five year-old and a snail, and opens out into the question of how mothers are seen, what kindness is, and how we try to protect our children from the realities that they will soon encounter.

Kindness to Snails

For a Five-Year-Old
Fleur Adcock

A snail is climbing up the window-sill
into your room, after a night of rain.
You call me in to see, and I explain
that it would be unkind to leave it there:
it might crawl to the floor; we must take care
that no one squashes it.  You understand,
and carry it outside, with careful hand,
to eat a daffodil.

I see, then, that a kind of faith prevails:
your gentleness is moulded still by words
from me, who drowned your kittens, who betrayed
your closest relatives, and who purveyed
the harshest kind of truth to many another.
But that is how things are: I am your mother,
and we are kind to snails.

Photo Two by Retiredplayboy / CC BY-SA (
Philippine orange tarantula (Orphnaecus philippinus) (Photo Two)

And finally, how about the tarantula? I rather love this poem by Thomas Lux, especially the last few stanzas.

Tarantulas on the Lifebuoy 


For some semitropical reason   
when the rains fall   
relentlessly they fall

into swimming pools, these otherwise   
bright and scary
arachnids. They can swim
a little, but not for long

and they can’t climb the ladder out.
They usually drown—but   
if you want their favor,
if you believe there is justice,   
a reward for not loving

the death of ugly
and even dangerous (the eel, hog snake,   
rats) creatures, if

you believe these things, then   
you would leave a lifebuoy
or two in your swimming pool at night.

And in the morning   
you would haul ashore
the huddled, hairy survivors

and escort them
back to the bush, and know,
be assured that at least these saved,   
as individuals, would not turn up

again someday
in your hat, drawer,
or the tangled underworld

of your socks, and that even—
when your belief in justice
merges with your belief in dreams—
they may tell the others

in a sign language   
four times as subtle
and complicated as man’s

that you are good,   
that you love them,
that you would save them again.

So, over to you Readers. Do you have a favourite poem that is loosely invertebrate-themed? I’m sure there must be lots of bee and butterfly and moth poems out there. I’d love to read them!

Photo Credits

Photo One by © Nevit Dilmen / CC BY-SA (

Photo Two by Retiredplayboy / CC BY-SA (

An Autumn Walk in Coldfall Wood

Cyclamen hederifolium in Coldfall Wood

Dear Readers, it has been so relentlessly wet for the past few days that I haven’t had the heart to brave the great outdoors. But today it dawned bright and cold, and so off we ran to the woods to see what had been going on. We were a little later than usual and so there were lots of dog walkers and children heading off to school, and you’d almost think things were back to normal were it not for the way most people are still instinctively leaping to one side to put six feet of distance between them and the next person.

Still, I was touched by the way someone had corralled the cyclamen into an enclosure to protect them. These are Cyclamen hederifolium as far as I can see, which is a wild native species, though these plants look rather more like the domesticated variety. Technically, people are not supposed to plant anything in a nature reserve, but I’m loathe to suggest that these particular plants be dug up when someone obviously has taken such care to protect them. I would say that as they naturalise the ‘fence’ will need to be moved out though.

Elsewhere, the woods are just starting to turn gold and orange. Everything feels poised on the cusp, ready to tumble into winter.

Hornbeam turning orange
Oak turning to copper

Along the path next to the allotments there is a burst of holly berries. They are so red that it’s startling. How can the birds possibly miss them? They even look delicious to me

And then it’s out on to the Fields, and I fall in love with the brambles all over again. Some of them are still in flower (and I’m sure that any late queen bumblebees will be delighted), but it’s the red of their foliage that is so striking. There is a legend that when St Michael cast the devil out of heaven, he landed in a bramble bush, which must have been most uncomfortable. So, he cursed it, and ever since the fruit is supposed to turn bitter after 29th September, St. Michael’s Day.

Bramble in flower

And look! The Japanese Knotweed is still in flower, though as far as pollination goes this isn’t an issue – in the UK all the plants are from one single female clone. Unfortunately, as we know, one single bit of rhizome results in a whole new plant. Still, at least the bees like it.

I got a little bit of a surprise when I heard this bird singing from the top of a shrub. I rather think it’s a dunnock, though the light isn’t very good. Who’d have thought that this shy, shrinking-violet of a bird would be advertising itself so vigorously at this time of year? Maybe, like so many plants and animals, it’s confused.

And then, with my eyes primed to see red, I noticed this street cherry tree on the way home. It has been horribly pruned at some point, and looks rather like a naiad trying to pull her way out of the trunk, but the colour! What a joy this time of year can be.

Saturday Quiz – Unleaving

Pin Oak (Quercus palustris) at the back of the Guildhall in the City of London)

Dear Readers, I have always been fond of the Gerard Manley Hopkins poem ‘Spring and Fall – to a Young Child’, which seems to me to sum up the human predicament.

Margaret, are you grieving
Over Goldengrove unleaving?
Leaves, like the things of man, you
With your fresh thoughts care for, can you?
Ah! as the heart grows older
It will come to such sights colder
By and by, nor spare a sigh
Though worlds of wanwood leafmeal lie;
And yet you will weep and know why.
Now no matter, child, the name:
Sorrow’s springs are the same.
Nor mouth had, no nor mind, expressed
What héart héard of, ghóst guéssed:
It is the blight man was born for,
It is Margaret you mourn for.

But it seems to me that part of the glory of the ‘unleaving’ is the extraordinary range of colours that the leaves achieve before their eventual demise. How brightly they shine at the end! Something to aspire to, surely. And so, for this week’s quiz, let’s have a look at some autumn leaves, and see if we can pair them up with their names. You have until 5 p.m. UK time on Thursday to pop your answers into the comments, and if you don’t want to be influenced by anyone speedier, write your cogitations down first :-).

I think this is a pretty tough quiz, and would be delighted with myself if I got half of them right, but then you lovely people always surprise me, so let’s see….

Onwards! Just match the photo to the species. So if you think photo 1) is of a horse chestnut, your answer is 1)a)

a) Horse Chestnut ( Aesculus hippocastanum)

b) Ginkgo (Ginkgo biloba)

c) London Plane (Platanus × acerifolia)

d) Ash (Fraxinus excelsior)

e) Weeping Willow (Salix babylonica)

f) Alder (Alnus glutinosa)

g) Swamp Cypress (Taxodium distichum)

h) English Oak (Quercus robur)

i) Beech (Fagus sylvatica)

j) English Elm (Ulmus minor)

k) Silver Birch (Betula pendula)

l) Sycamore (Acer pseudoplatanus)

m) Wild Service Tree (Sorbus torminalis)

n) Rowan (Sorbus aucuparia)

o) Hawthorn (Crataegus monogyna)

Photo One by Liz West from Ash
Photo Two by Peter O'Connor from Beech
Photo Three by AnemoneProjectors / CC BY-SA ( English Oak
Photo Four by By Famartin - Own work, CC BY-SA 4.0, Weeping willow
Photo Five by Stefan.lefnaer / CC BY-SA ( Alder
Photo Six from English elm
Photo Seven from the Trees for Cities website
Photo Eight by Famartin / CC BY-SA ( hawthorn
Photo Nine by Rosenzweig / CC BY-SA ( Wild Service Tree
Photo Ten by Leonora (Ellie) Enking at
Photo Eleven by Marija Gajić / CC BY-SA ( Sycamore
Photo Twelve by Ninjatacoshell / CC BY-SA (
Public Domain (Ginkgo biloba)
Photo Fourteen by By Rosser1954 - Own work, CC BY-SA 4.0, Silver Birch
Swamp cypress

Surprise Quiz! – What’s That Fruit – The Answers

Cultivated rose hips

Dear Readers, this week’s joint winners were Sylvie, Christine, Isla and Fran and Bobby who all got a full house of 15 out of 15, with Anna also doing brilliantly with 11 out of 15. Well done to all of you, and keep your eyes open for another autumnal quiz at the weekend….

Photo One by Edal Anton Lefterov / CC BY-SA (

1) i) Elder (Sambucus nigra)

Photo Two by Ian Cunliffe / Blackthorn fruit (sloes) - Prunus spinosa

2) g) Blackthorn (Prunus spinosa)

Photo Three by Dennis Jarvis from Halifax, Canada / CC BY-SA (

3) o) Rowan (Sorbus aucuparia)

Photo Four by Brian Robert Marshall / Hawthorn berries, Postern Hill, Savernake Forest

4) e) Hawthorn (Crataegus monogyna)

Photo Five by grassrootsgroundswell / CC BY (

5) j) Yew (Taxus baccata)

Photo Six by Dcrjsr / CC BY (

6) k) Juniper (Juniperus communis)

Photo Seven by Arnstein Rønning / CC BY-SA (

7) l) Barberry (Berberis vulgaris)

Photo Eight by Zeynel Cebeci / CC BY-SA (

8) c) Cherry Laurel (Prunus laurocerasus)

Photo Nine by Ragesoss / CC BY-SA (

9)a) Blackberry (Rubus fruticosus agg.)

Photo Ten by Randi Hausken from Bærum, Norway / CC BY-SA (

10) b) Cloudberry (Rubus chamaemorus)

Photo Eleven by Rosser1954 / CC BY-SA (

11) n) Sea Buckthorn (Hippophae rhamnoides)

Photo Twelve by Peter O'Connor aka anemoneprojectors from Stevenage, United Kingdom / CC BY-SA (

12)d) Dog Rose (Rosa canina)

Photo Thirteen by Jan Sørensen / CC BY (

13) m) Burnet Rose (Rosa spinosissima)

Photo Fourteen by Rosenzweig / CC BY-SA (

14) h) Wild Service Tree (Sorbus torminalis)

Photo Fifteen by Jesse Taylor / CC BY-SA (

15) f) Snowberry (Symphoricarpos albus)

Photo Credits

Photo One by Edal Anton Lefterov / CC BY-SA (

Photo Two by Ian Cunliffe / Blackthorn fruit (sloes) – Prunus spinosa

Photo Three by Dennis Jarvis from Halifax, Canada / CC BY-SA (

Photo Four by Brian Robert Marshall / Hawthorn berries, Postern Hill, Savernake Forest

Photo Five by grassrootsgroundswell / CC BY (

Photo Six by Dcrjsr / CC BY (

Photo Seven by Arnstein Rønning / CC BY-SA (

Photo Eight by Zeynel Cebeci / CC BY-SA (

Photo Nine by Ragesoss / CC BY-SA (

Photo Ten by Randi Hausken from Bærum, Norway / CC BY-SA (

Photo Eleven by Rosser1954 / CC BY-SA (

Photo Twelve by Peter O’Connor aka anemoneprojectors from Stevenage, United Kingdom / CC BY-SA (

Photo Thirteen by Jan Sørensen / CC BY (

Photo Fourteen by Rosenzweig / CC BY-SA (

Photo Fifteen by Jesse Taylor / CC BY-SA (

The End of the Megafish?

Photo One byBy Максим Яковлєв - Own work, CC BY-SA 4.0,
Beluga sturgeon (Huso huso) Photo One

Dear Readers, my go-to source for all things scientific is New Scientist. What a treasure trove it is! I love the way that it makes me consider things that had never crossed my mind before. And this week, there is an article about the neglected giant river fish that are quietly disappearing.

A megafish is defined as any freshwater species which weighs more than 30kg (the weight of an adult golden retriever). 206 species fall into this category, and many can reach a much greater size than the criteria stipulated

The beluga sturgeon (Husa husa) is the largest, and it’s critically endangered. The largest specimens can measure 7 metres long and weigh 1.5 tonnes. These huge individuals may be extremely old – sturgeons take 20 years to reach maturity, and it is likely that they can live to be a hundred, if they get the chance. They used to be found in rivers all over Europe, and even today if you should happen to catch a sturgeon in an English river ( a most unlikely event, but it’s as well to be prepared) you will need to hand it over to the Queen as it’s been a Royal Fish since 1362. Sadly, Beluga sturgeon are critically endangered because of the taste for their eggs: a single fish can provide a poacher with 30,000 euros’ worth of caviar. The fish can be farmed, but the product is apparently inferior. Once found throughout the Adriatic, Caspian and Black Seas, the sturgeon is now listed as Critically Endangered.

Still, the beluga sturgeon is better off than the poor old Chinese Paddlefish (Psephurus gladius) which is now thought to be extinct. They have been overfished, and then their migratory route had a hydroelectric dam built across it. Then the river became increasingly polluted, and the volume of shipping was also a challenge. The last live fish – a 3.6 metre-long female – was caught in 2003, but by this stage she was probably ‘dead fish walking’ (or swimming) because a search of the Yangtze basin in 2017 and 2018 didnt turn up a single fish. The scientists who broke the news described the extinction as a ‘reprehensible and irreparable loss’.

Photo Two byBy Zheng Zhong(Life time: 1612-1648 (years active)) - Original publication: Nanjing, China, early-mid 17th centuryImmediate source: Metropolitan Museum of Art, PD-US,
17th Century depiction of a paddlefish (Photo Two)
Photo Three By Alneth - Own work, CC BY-SA 4.0,
Chinese paddlefish in the Wuhan Museum of Hydrobiological Sciences (Photo Three)

The loss of the Chinese paddlefish does seem to have focussed the minds of the Chinese government – they have been working with various conservation bodies to develop ways of protecting their ecosystems, and have introduced a moratorium on fishing in 332 designated areas. However, while there are still the dams and the pollution there’s a long way to go.

Lest we in Europe start feeling too superior, though, let us note that the Danube is the river considered the worst in terms of threats to biodiversity. And a recent report that every single one of England’s rivers was polluted should also give us pause. Fish really do have nowhere else to go if their habitat is damaged, poor things.

Still, as we all have enough to feel sad about at the moment, here are a few happier stories. When I was younger I often used to hang out at the aquarium at London Zoo, where there were some of the biggest fish that I’d ever seen. Pirarucu (otherwise known as arapaima) are huge fish that have to breathe air – they come to the surface to gulp in some oxygen via a special organ called the labyrinth, which enables the animal from the atmosphere. This is probably an adaptation to the sluggish, under-oxygenated waters of the Amazon where the fish lives. It seems to do very well in aquariums, but it is also bouncing back in the wild – on the Juruá river, which feeds into the Amazon basin, sustainable projects have enabled this amazing fish (which can grow to a length of three metres) to start to increase in population.

Photo Four By George Chernilevsky - Own work, Public Domain,
Pirarucu (Arapaima leptosoma) in Sevastopol Aquarium (Photo Four)

And although the Chinese paddlefish seems to be lost, the American paddlefish (Polyodon spathula), is now a protected species throughout its last haven, the Mississippi and Missouri basins. This poor fish was not only fished for sport, but also for its caviar. They are nearly blind, because they don’t need to see in the muddy waters, but they do have electroreceptors not only on their sensitive ‘paddles’ but also on most of their body, which enables them to pick up the swarms of tiny zooplankton that they feed upon. They then open their mouths and suck the little animals in.

Photo Five byBy Хомелка - Own work, CC BY-SA 3.0,
Paddlefish (Photo Five)

Although the Mississippi basin is an extremely degraded environment, the American paddlefish seems to be doing ok, and is even increasing in numbers. It would be really something if we were able to save the last species of these giant fish before they’re lost forever.

Photo Credits

Photo One By Максим Яковлєв – Own work, CC BY-SA 4.0,

Photo Two By Zheng Zhong(Life time: 1612-1648 (years active)) – Original publication: Nanjing, China, early-mid 17th centuryImmediate source: Metropolitan Museum of Art, PD-US,

Photo Three By Alneth – Own work, CC BY-SA 4.0,

Photo Four By George Chernilevsky – Own work, Public Domain,

Photo Five By Хомелка – Own work, CC BY-SA 3.0,

Wednesday Weed – Avocado

Dear Readers, if there is a more frustrating fruit on the face of the earth than the avocado I have yet to meet it (though the peach runs it pretty close). How can it go from rock hard to rotten without any intervening period of ripeness? Even the gentlest cupping to check for softness leads to a horrible brown bruise. It doesn’t help that I can’t abide the things if they’re the texture of rubber or reduced to mush either. And yes, I know I’m difficult to please.

One avocado-based activity that is fun, though, is how easy the stones are to turn into a rather attractive house plant. I can’t be the only one who has balanced the seed on some toothpicks above a jar of water and watched as the leaves bust out of the top.

One method for propagating avocados (Public Domain)

I have, of course, never persuaded the plant to produce any more baby avocados, but then what’s the point? They’ll only disappoint me yet again.

Photo One byBy B.navez - Own work, CC BY-SA 3.0,
The Avocado in situ (Persea americana) (Photo One)

The avocado plant comes originally from Mexico, and is a member of the Lauraceae or laurel family (not really a surprise when you look at those leaves). The fruit is technically a large berry, and it has the handy attribute, as we know, of ripening after picking. The ‘ready to eat’ avocados that you see in the shops have been exposed to ethylene in a ‘ripening room’ – ethylene is produced most noticeably by bananas, and light dawns as I begin to see that my poor avocados have probably been being stored too close to my fruit bowl, which would explain a lot.

All of today’s avocados come from the criollo, the ancestral form of the avocado. This was being cultivated as long ago as 5000 BCE, and eaten from the wild tree long before this: an avocado pit was discovered in the Coxcatlan Caves of Tehuácan in Mexico that dated to about 10,000 years ago. And small wonder that our ancestors enjoyed it: it has lots of Vitamin K and Vitamin C, and is a source of both saturated and unsaturated fats.

Photo Two byBy Nsaum75 at English Wikipedia, CC BY-SA 3.0,
The ancestral avocado or criollo (Photo Two)

The avocado goes back much further than 10,000 BCE however. Like many fruits with large stones, it is believed to have evolved with the megafauna of the Pleistocene, who would have eaten the avocado whole and then deposited the stone, with a handy heap of dung, some distance away. Possible candidates for this dispersal process would be the giant ground sloth or megatherium, and the gomphotheres, a group of ancient elephants. Strangely enough, the skin and flesh of avocados is harmful to most domestic animals, and some humans are also allergic to it.

Photo Three byBy Marcus Burkhardt - Own work, CC BY 3.0,
Megatheriums (giant sloths) (Photo Three)
Photo Four By Unic - Own work, CC BY-SA 3.0,
Gomphotheres (Photo Four)

Now, no current animals in Central America are big enough to disperse avocados, and indeed their propagation can be something of a problem. The tree takes a long time to mature, and commercial growers depend on grafting to get the fruit to ‘come true’. Furthermore, the plant will sometimes produce tiny seedless avocados called ‘cucks’ – you might think that the growers would be delighted, but sadly the size of the fruit makes them nothing to get excited about, although some enterprising farmers do sell them as ‘cocktail avocados’. Some varieties, such as the ever-popular Hass, don’t crop regularly every year, with a bumper year followed by a ‘meh’ year (technical phrase).

Photo Four byBy Nsaum75 at English Wikipedia, CC BY-SA 3.0,
A seedless avocado or ‘cuke’ growing alongside its bigger siblings (Photo Four)

Now, although I can never find an avocado at the perfect pitch of ripeness, there is no denying that an avocado can be a thing of absolute beauty. And goodness, is it a versatile ingredient! Of course there’s the standard avocado on toast, though I always think that a warm egg on top of cold avocado is a bit of a strange thing. But guacamole? Now you’re talking. And I’m increasingly seeing avocado being used in vegan cooking, wherever you need something fatty and unctuous.

And how about an Indonesian avocado ‘milk’ shake with chocolate syrup? I think the jury’s out on this one as far as I’m concerned.

Indonesian-style avocado milkshake with chocolate syrup

Incidentally, I have seen (and even on one occasion made) recipes that include baked avocados, but in my experience the heat turns them bitter. Any thoughts, readers?

And I rather like the sound of this Ethiopian drink – ‘It is also common to serve layered multiple fruit juices in a glass (locally called Spris) made of avocados, mangoes, bananas, guavas, and papayas‘.

Photo Six from
Spris in Addis Ababa, Ethiopia (Photo Six)

Now readers, you would not want me to leave the subject of avocados without sharing a little of the folklore around them. They have something of a reputation as an aphrodisiac, probably because their shape could put one in mind of a testicle if one was that way inclined. But the piece de resistance is this wonderful tale from Guiana, recounted on Richard Niesenbaum’s blog. It’s one of those stories that just keeps getting worse and worse. See what you think.

According to Aztec legend, a man named Seriokai living in Guiana, a country in South America, loved avocados and usually spent the day gathering them. One day while he was out, a tapir wandered into his camp and made Seriokai’s wife fall in love with it. The next day, Seriokai and his wife went out to collect avocados. As he climbed down one tree, his wife hit him over the head, causing him to fall and sever his leg. She ran away with the tapir and the basket of avocados. A neighbor found Seriokai and helped him heal, replacing his leg with a wooden stump. Seriokai then followed the trail of growing avocado trees that had grown as they fell out of his wife’s basket. He found the runaway couple at the end of the world, and shot the tapir in the eye. The tapir leaped off the edge from the pain, and Seriokai’s wife followed her love and jumped as well. Seriokai also jumped off, and the three are said to have turned into Orion (Seriokai), Pleiades (the wife) and Hyades (the tapir with a bleeding eye) in the sky (Neal 2017).

So there you go. And here is a tapir, just in case you’ve never seen one. Not an obvious love object, but people can be very idiosyncratic.

Photo Six from 
Vauxford / CC BY-SA (
A very attractive Brazilian tapir (Photo Six)

And finally, a poem. This makes me happy/sad – I have two colleagues who are just off on their maternity leave and I am both envious of them and resigned. Sometimes, the things that we hope for in life just don’t work out, and not managing to have children will be something that makes me a little melancholy for the rest of my days, I suspect. Still, there are plenty of children and animals who need love, so I will never be short of somewhere to put all that sweetness.

Eating the Avocado


Now I know that I’ve never described
anything, not one single thing, not
the flesh of the avocado which darkens
so quickly, though if you scrape
what’s been exposed to the air it’s new-green
beneath like nothing ever happened.
I want to describe this evening, though
it’s not spectacular. The baby babbling
in the other room over the din
and whistle of a football game, and now
the dog just outside the door, scratching,
rattling the tags on her collar, the car
going by, far away but loud, a car without
a muffler, and the sound of the baby
returning again, pleasure and weight.
I want to describe the baby. I want to describe
the baby for many hours to anyone
who wishes to hear me. My feelings for her
take me so far inside myself I can see the pure
holiness in motherhood, and it makes me
burn with success and fear, the hole her
coming has left open, widening. Last night
we fed her some of the avocado I’ve just
finished eating while writing this poem.
Her first food. I thought my heart might burst,
knowing she would no longer be made
entirely of me, flesh of my flesh. Startled
in her amusing way by the idea of eating,
she tried to take it in, but her mouth
pushed it out. And my heart did burst. 

Photo Credits

Thoughts from an Open University Course 3 – Deep Time – Lessons from Geology

Photo One from
Bacterial fossils from the Fig Tree chert formation in South Africa (Photo One)

Dear Readers, this week my OU course was concentrating on the concept of Deep Time, and so I thought I’d share a bit of what I’ve learned with you, to see if I’ve understood it myself. Consider yourselves guinea pigs! And all questions and comments gratefully received, as always.

The earth has been in existence for approximately 4.6 billion years, and while humans are a very recent addition, the first bacterial life popped up as long ago as 3.5 billion years. Some tiny fossils have been discovered in rocks known as the Fig Tree chert in South Africa, and these appear to be caused by the first bacteria, who lived in those ancestral oceans. If you look closely, you can actually see those ancient life-forms dividing, just as they do now. Other fossils show lines of bacteria joined together in long filaments. It’s thought that these bacteria were the fore-runners of the cyanobacteria that came into their own a mere 3 billion years ago (see below), and like them, they lived in the oceans, where all life originated and where, for most of Earth’s history, it stayed.

Chert is a sedimentary rock, usually composed of siliceous ooze – this was the bacteria-rich deep ocean floor, where bacteria both lived and died. Flint nodules are a form of chert, as are agate, onyx, opal and jaspar. How easy it would have been to miss the tiny bacterial fossils, and indeed for a long time they were contentious. However, the finding of similar patterns in cherts in Greenland and Canada seems to have settled the issue – there were bacteria on earth, quietly dividing and getting on with their lives, a billion and a bit years after the earth first formed from space debris.

Photo Two by By Minghong - Own work, CC BY-SA 3.0,
A layer of erosion-resistant chert in the Tung Ping Formation in Hong Kong (Photo Two)

These tiny bacteria are already beginning to affect the atmosphere by producing nitrogen, but for oxygen to be produced, we have to wait for the appearance of the cyanobacteria 3 billion years ago. Also known as blue-green algae, these organisms are still with us today – they create long filaments that mix with sediment and form molehill-like structures called stromatolites. Because they photosynthesize, turning energy from the sun into oxygen, these creatures slowly begin to produce the key ingredient of the air that we breathe.

Fossilized stromatolites from Banff, Canada (Public Domain)
Photo Three by By Paul Harrison - Photograph taken by Paul Harrison (Reading, UK) using a Sony CyberShot DSC-H1 digital camera., CC BY-SA 3.0,
Modern stromatolites in Shark Bay, Australia (Photo Three)

So, the cyanobacteria work away over millenia, releasing oxygen into the oceans. However, at first it doesn’t stay there. Oxygen is an extremely reactive gas, and at this point there are endless sulphur and iron-rich rocks laying about. These absorb the oxygen to start with, preventing it from becoming available to anything that might be able to breathe it. In the early years, iron-rich rocks are banded in green and white: this is thought to show that the iron has reacted with the oxygen released into the sea water, turning it green (all such banded rocks come from the ocean).

These banded iron deposits may show that, to begin with, the cyanobacteria could be poisoned by their own waste product (oxygen) when it built up too much, hence the periods when the iron was oxygenated, followed by periods when the algae died back and there was just sediment. Later, the bacteria evolved to be able to protect themselves from this poisoning, and this signalled the start of the Great Oxygenation Event of about 2 billion years ago. Nonetheless, the iron deposits that we mine today are largely banded iron formations (BIFs).

Photo Four from
Banded iron formation (Photo Four)

Once all the iron in the ocean has been used up, we start to see bright red, iron and oxygen-rich rocks instead, which shows that there was a constant supply of oxygen produced by the cyanobacteria. A tipping point has been reached, and the oxygen not only oxygenates the oceans, but starts to leak into the atmosphere as well.

Ironstone (Public Domain)

The effect on the atmosphere is two-fold. Firstly, the oxygen displaces the carbon dioxide and methane, leading to cooling, and possibly the first period of global glaciation – some have called this ‘snowball earth’. Secondly, an oxygen-rich enviroment seems to make it possible for more complex forms of life to appear, and for cells who carry their genetic material in their nucleii to develop. Between 700 million and 545 million years ago, many forms of multicellular life appear for the very first time. The Earth is no longer ruled purely by bacteria. By about 440 million years ago we are gearing up for the First Mass Extinction event, but for now life is starting to diversify and become rich in a way never seen before. It’s the age of the trilobite, and of many other creatures besides. This is the era of the Burgess Shale, and it’s almost as if nature is trying out many forms of life that we can’t even begin to understand now. What a remarkable time period this would be to study! What I’m loving about my course is the sheer variety of paths that it explores. Who knows which of them I’ll decide to come back to?

Photo Five from
Trilobite (Photo Five)
Photo Six by Todd Gass,_Blackberry_Hill,_Wisconsin,_Cambrian_-_Todd_Gass.jpg#/media/File:Climactichnites_wilsoni,_Blackberry_Hill,_Wisconsin,_Cambrian_-_Todd_Gass.jpg
Tracks of a Cambrian ‘sea-slug’ ( Climactichnites wilsoni) from Blackberry Hill, Wisconsin (Photo Six)
Photo Seven from By James St. John - Agnostus pisiformis fossil trilobites (Alum Shale Formation, upper Middle Cambrian; Andrarum, Scania, Sweden) 5, CC BY 2.0,
Mass of fossil trilobites (Agnostus pissiformus) from Sweden (Photo Seven)

Photo Credits

Photo One from

Photo Two By Minghong – Own work, CC BY-SA 3.0,

Photo Three By Paul Harrison – Photograph taken by Paul Harrison (Reading, UK) using a Sony CyberShot DSC-H1 digital camera., CC BY-SA 3.0,

Photo Four from

Photo Five from

Photo Six by Todd Gass,Blackberry_Hill,_Wisconsin,_Cambrian-Todd_Gass.jpg

Photo Seven from By James St. John – Agnostus pisiformis fossil trilobites (Alum Shale Formation, upper Middle Cambrian; Andrarum, Scania, Sweden) 5, CC BY 2.0,

Netflix – My Octopus Teacher

Photo One By SeaChangeProject - Own work, CC BY-SA 4.0,
Photo One (see below)

Dear Readers, Netflix has been a life-saver over the past few years. When Mum died, I spent a lot of my time on the sofa, wrapped in a blanket and unable to do anything sensible. Instead, I watched the whole back catalogue of The Great British Bake-Off, Project Runway, and ten whole series of RuPaul’s Drag Race.

Then, when I became a (part-time) working woman, I had a lot less time, and so it was all about an hour’s simultaneous knitting and watching after work. It’s amazing how many episodes of First in Fashion, Masterchef-The Professionals and Sugar Rush you can get through if you multitask.

But in lockdown, I find that Saturday nights are often spent huddled in front of a ‘proper’ film. I’m still not happy about going to the cinema, what with our Covid-19 numbers doubling every week, and so sitting on the sofa with a cup of tea has much to recommend it. And so it was that this week we settled in to watch a documentary about a man free-diving in the kelp forest off the coast of South Africa, and his relationship with a wild octopus.

Craig Foster is a wildlife film maker, and yet it’s clear that life has lost its meaning. He spent time with the San people of the Kalahari desert and was inspired by how they are so much part of their environment. For Foster, there’s a strong sense that he no longer wants to be a mere observer, he wants to be part of something. And it’s this that drives him to start free-diving in the freezing waters. Over the course of a year he learns to hold his breath for longer, and he makes a decision early on to eschew the comfort of a wet suit. This is a man who desperately wants to belong to something bigger than himself.

And then, he meets the octopus. When he first sees her, she is covered in shells and sea urchins, and the fish are moving curiously around her. Foster doesn’t realise that she’s an octopus until she bolts for her den. He feels an instant connection with her. How he knows that she’s a ‘she’ is one of the unanswered questions of this documentary. If you are hoping to find out a lot more about cephalopods I’m afraid that you’ve come to the wrong place because although there are lots of observational snippets about the extraordinary intelligence of the animal, the context doesn’t come out of this film.

In other words, it’s more of a Netflix film than an episode of The Natural World on the BBC – it’s about one man’s ‘journey’ to understand a wild animal, and his feelings about her. It’s about how she changes his view of the world, and of his relationship with his son.

This is not to say that Foster doesn’t map not only the geographical features of the area where the octopus lives, but all the different interactions between predators and prey. I feel that he really is immersed in the life of the kelp forest, and I could relate to the way that he wants to be part of what’s going on. The way that he decides to dive in the same small area every day speaks to me of how he wants to go deeper. I am reminded of Mary Oliver’s poem ‘When Death Comes’:

I don’t want to end up simply having visited this world.’

However, there is little of this complexity in the film. We see the nuanced approaches that the octopus takes to the different kinds of sea creatures that she eats: one theory as to why octopuses (which are, after all, molluscs like snails and slugs) are so intelligent is because of the varied prey that they must deal with. Most animals that are ‘intelligent’ by our standards are social animals, who are thought to have developed their large brains to deal with complex interactions, but octopuses are extremely anti-social, except when they breed.

We also see the ways that the octopus outwits her most persistent predator, the pyjama shark – the scenes of the shark hunting by scent for ‘our’ octopus are nerve-wracking. And we see the octopus playing, and the way that she curiously interacts with Foster. What is she getting out of these encounters? Foster is extremely careful to be respectful of her and to not interrupt her day to day life, and is deeply remorseful if he frightens her. Nonetheless, I can’t help but feel a little uncomfortable that this short-lived animal has not only Foster but another cameraman popping in to see her on a regular basis. I admire that Foster generally doesn’t intervene to protect the octopus, which must have been very difficult, but I still wonder how things changed because he was there. We never really know what we do, because however much we want to be part of a habitat we are still big clumsy animals. I am reminded that people who live in areas of Nepal where there are tigers consider the highest respect that they can pay to the animal to be to never see it.

Still, this is a lovely film, with some stunning underwater shots. I liked Foster a lot, and admired his dogged determination. I love that his relationship with his son blossomed as a result of his experiences, and that he has founded a charity, The Seachange Project, to protect the kelp forest. It’s just that the octopus, who could have been the star, is instead just the catalyst for Foster’s dramatic rebirth. As Elle Hunt puts it in The Guardian,

if a documentary’s success is measured by how well it represents its subject, I’d say My Octopus Teacher falls short.’

Let me know what you think! Am I just being a curmudgeon? It wouldn’t be the first time…

And here’s the official trailer. Enjoy!

Ivy – An Environmental Friend?

Photo One by Daderot at en.wikipedia / CC BY-SA (
Ivy -covered house, Boston Massachusetts (Photo One)

Do you look at this picture and shudder in horror? Or does it fill your heart with happiness that someone has created such a wildlife-friendly vertical habitat? Well, I think for me it’s a mixture of both. But in New Scientist last week, writer Clare Wilson suggests that an ivy-covered wall can have lots of benefits that I for one hadn’t considered.

I have always admired the splendid ‘plant walls’ that are being created, both indoors and out, but they seem to be very difficult to maintain – the requirements for watering, feeding and protection from exposure seem daunting. When it’s done well, it can be spectacular.

Photo Two from
Green wall at the Athenaeum Hotel on Piccadilly (Photo Two)

However, most of us don’t have the money, time or know-how to create something like this. Wilson suggests that the Hedera species are a quick way of covering an ugly outbuilding or fence, and notes that birds like the berries, and many pollinators relish the flowers, including the recently-arrived ivy bee.

Photo Three by Charles J Sharp / CC BY-SA (
Ivy bee (Colletes hederae) (Photo Three)

However, there are other benefits to an ivy-covered wall. For one thing, it can help to insulate your building. In a study by Tijana Blanusa at the University of Reading, it was found that ivy helped to slightly warm a room in winter. It also cools a room in summer both through creating shade and through the water evaporation from its leaves. It is better than either Boston ivy (Parthenocissus tricuspidata) or climbing hydrangea (Pileostegia virburnoides) at reducing the temperature in summer, probably because the leaf cover of ivy is so dense.

But, I hear you say, doesn’t it also destroy my walls? The RHS say that ivy doesn’t normally damage walls unless the masonry is already cracked – the aerial roots of ivy can’t penetrate sound mortar. Having said this, though, Wilson admits that once ivy gets going it can take over very quickly – in fact, she recommends only growing it where you’re happy to get on a ladder and prune back any eager shoots that are reaching for gutters or roof tile. Apparently anti-graffiti paint also works: it contains an ingredient called silane which reduces the attachment of the roots.

Wilson also suggests containing the plant by popping it into a pot, or putting it in a small patch with a few bricks – the words ‘good luck with that’ spring to mind, as in my experience you only have to go on holiday for a fortnight to come back and find that your garden has been transformed into an ivy-covered version of the Sleeping Beauty’s bower. Still, this is an extremely useful wildlife plant in the right place, and one of the very last sources of pollen and nectar for autumn insects.

Photo Four by gailhampshire from Cradley, Malvern, U.K / CC BY (
Myathropa florea hoverfly on ivy flowers (Photo Four)

I should probably put in a word here too about ivy in forests. I know people who loathe the way that the plant seems to smother trees, although it is only using the branches and trunk as a support. According to the BBC, ivy will not normally harm a healthy tree, which is big and strong enough to continue to photosynthesise in spite of its ‘hanger-on’. However, trees which are already weakened through disease or age can be brought down by the sheer weight of ivy, especially in high winds. I can think of a couple of trees at the edge of Coldfall Wood which are gradually being brought down by the volume of ivy.

Photo Five by Paul Hutchinson / Ivy covered tree, Marldon Lane
Ivy-covered tree (Photo Five)

On balance though, my personal belief is that ivy can be a good friend if you keep an eye on it in the garden, and tolerate it in other places. As we go into winter, it provides places for all kinds of animals to roost and hibernate, and it can brighten up all kinds of miserable concrete structures that would otherwise be an ecological desert. But what do you think? Let me know whether you’ve had to wrestle this plant to the ground, or if you have fallen in love with it. I’d love to know.

Surprise Quiz! – What’s That Fruit?

Cultivated rose hips

Dear Readers, it’s that time of year when the trees and hedges are laden down with berries and hips and haws. The thrushes are ecstatic, and if you keep your eyes open you might even be able to spot some waxwings later in the year. But how many of those pretty shiny fruits  can you identify?

Match the photo to the list below (so, if you think photo 1 is a blackberry, your answer is 1) a) ).

You have until 5 p.m. next Thursday (8th October) to post your answers in the comments if you want to be marked ( write your answers down on a piece of paper first if you don’t want to be influenced by speedier people).

Have fun!

a) Blackberry (Rubus fruticosus agg.)

b) Cloudberry (Rubus chamaemorus)

c) Cherry Laurel (Prunus laurocerasus)

d) Dog Rose (Rosa canina)

e) Hawthorn (Crataegus monogyna)

f) Snowberry (Symphoricarpos albus)

g) Blackthorn (Prunus spinosa)

h) Wild Service Tree (Sorbus torminalis)

i) Elder (Sambucus nigra)

j) Yew (Taxus baccata)

k) Juniper (Juniperus communis)

l) Barberry (Berberis vulgaris)

m) Burnet Rose (Rosa spinosissima)

n) Sea Buckthorn (Hippophae rhamnoides)

o) Rowan (Sorbus aucuparia)

Photo One by Edal Anton Lefterov / CC BY-SA (


Photo Two by Ian Cunliffe / Blackthorn fruit (sloes) - Prunus spinosa


Photo Three by Dennis Jarvis from Halifax, Canada / CC BY-SA (


Photo Four by Brian Robert Marshall / Hawthorn berries, Postern Hill, Savernake Forest


Photo Five by grassrootsgroundswell / CC BY (


Photo Six by Dcrjsr / CC BY (


Photo Seven by Arnstein Rønning / CC BY-SA (


Photo Eight by Zeynel Cebeci / CC BY-SA (


Photo Nine by Ragesoss / CC BY-SA (


Photo Ten by Randi Hausken from Bærum, Norway / CC BY-SA (


Photo Eleven by Rosser1954 / CC BY-SA (


Photo Twelve by Peter O'Connor aka anemoneprojectors from Stevenage, United Kingdom / CC BY-SA (


Photo Thirteen by Jan Sørensen / CC BY (


Photo Fourteen by Rosenzweig / CC BY-SA (


Photo Fifteen by Jesse Taylor / CC BY-SA (