The Trilobites and After

The Trilobites and After, recited by Ashley Gérardy

Ere Snowdon raised its lofty head above the Cambrian Sea
King Paradoxus called his sons—and many sons had he.
He looked around—and looking, was an action quite profound—
For his eyes were very rigid: ‘twas his body that turned round.

‘My sons,’ he said, ‘our neighbours, whether Brachiopod or Cystid,
Contentedly upon their stalks on sea-soup have existed,
The Graptolites that drift around have never done us hurt,
And we, detritus-feeders, have survived the dust and dirt.

‘But a uniform environment of blue-black marl and mud
Has not induced variety, and variety is good.
The sea is getting deeper and the land is rising higher,
We’re doomed unless we take some steps to get above the mire.

‘I know we’re not for enterprise ideally designed:
We’re over-squat, with feeble legs exactly of one kind:
But if some of you would go ashore and change your respiration,
You might improve on what you see, and work a reformation.’

The Paradoxus joined his sires, and the shore went up and down,
And every year adventurous sons would frizzle up or drown,
Until they learnt the tidal ways and from the sun took shelter,
Instead of getting all bemused and wandering helter-skelter.

And after seven million years and countless oscillations
Beside a geyser lake there met two parted generations:
Lepidocaris in the water was paddling near the shore,
And Athropleura on the bank peered over more and more.

‘Hallo!’ said Carrie, ‘surely you are one of my lost cousins?’
‘O.K.’ said Arty, ‘in the sea I knew your lot by dozens.
But how you’re changed! Have you been ill? Unless the light’s too dim,
Your pleura seem to droop a lot, and you seem very slim.’

Carrie thereon indignantly sashed off across the lake,
And Arty realised he’d made a very big mistake.
But Carrie on returning said: ‘You needn’t talk of slimming!
What I have done, as you now see, has been for better swimming.’

‘Sorry, my dear,’ then Arty said, ‘I made a stupid blunder.
Old Paradox would hail you as a Trilobital wonder!
The way you’ve made your exopods work freely with your endo’s
Is marvellous, a triumph of evolutional crescendos.’

‘Indeed it wasn’t easy,’ Carrie then to him admitted,
‘Our exopods, ‘twixt endopods and pleura tightly fitted,
Had barely room to oscillate within their latticed cage,
And the endopods’s slow movements put me daily in a rage!

Then once, when trying to spurt a bit with those horizontal oars,
They tangled with the exopods above the pleural floors;
So recklessly I wrenched them out and worked the lot as one,
And really thought I’d done the trick—and nearly was undone.’

‘Why, what do you mean?’ asked Arty. ‘You got them free at last,
And I’m sure no other Trilobite e’er traveled half as fast.’
‘Oh, now’s all right,’ said Carrie, ‘but at first ‘twas touch and go!
My endo’s wouldn’t feather, and my exo’s wouldn’t row!

‘So awful trouble followed with my pleural respirations,
I had to work my antennae hard to avoid asphyxiation.’
‘I’m jolly glad you managed,’ Arty said, ‘I wish that I
had never left the water, for I might have helped near by.’

And then he told her how he’d lived for months upon the shore,
Exploring every crevice that held water on the floor,
Until by coming out by night and keeping damp with spray
He almost was acclimatised to breathing any way:

‘But what’s the good? Compared with you, I’m rubbish on the ground,
Condemned to keep below by day and never move around.
What have I gained by leaving the old mud-banks after all,
When now I’m doomed for ever just to burrow and to crawl?’

But Carrie, as Arty sadly spoke, grew more and more excited,
And when he’d finished, said: ‘My lad, you’re far from being blighted;
You left the mud-banks after me, but have really done much more,
For you’ve won a new environment. Your triumphs lie before!

‘Like me, I see, you’ve sprung a hinge upon your pleural flaps!
With me they’re bound to dwindle, but with you (who knows?) perhaps
When your method of air-breathing has made a further slight advance
You’ll lengthen out those pleural wings and gaily with them dance
In wider realms of airy space than I shall ever know!
Go, therefore, Arty, cheerfully—with my best wishes, go!’

She swam away, and when she’d gone, with a fearful rumbling roar
The boiling geyser burst again and flooded lake and shore—
Wee Lepidocaris was lost, then and for evermore,—
At least till Mr. Scourfield found and pieced her sad remains,
And told the tale we here re-tell in slightly altered strains.

Walter Garstang- likely written between 1907 & 1949, published in 1951

This poem was featured in Larval forms, and other zoological verses, a poetry anthology by Walter Garstang that features mainly poems about invertebrates. Though published two years after his death in 1951, Walter wrote most of his poems before 1922 (the date for this particular poem is unfortunately not available). In the introduction, the marine biologist Sir Alistair Hardy writes that the verses "were clearly intended by their author for the genuine student who is thoroughly familiar with the technical terms used in Zoology."

The natural history of this poem

The Trilobites and After explores the evolutionary history of the group Arthropoda, a group of animals with a jointed exoskeleton that includes insects, arachnids and crustaceans as well as some extinct groups including trilobites (if you’d like to know more about trilobites, check out our feature on Ode to a Trilobite by Timothy Abbott Conrad).

In this poem, Paradoxus is treated as the ancestor of other trilobites and all future arthropods. It should be noted that Paradoxus likely was meant to be named Paradoxides, a trilobite from the Cambrian (538.8 – 485.4 million years ago), while Paradoxus is the name for a genus of moths in Europe. Also, although they were some of the earliest diversifying arthropods, trilobites are not the ancestor of all arthropods, instead belonging to a separate extinct branch of the family tree. Paradoxus proclaims to his sons (other trilobites and arthropods) that they have all been living in a “…uniform environment…” and that they should “…induce variety…” by doing things should do things like “…go[ing] ashore and change your respiration…”. This alludes to how arthropods have adapted to many modes of life in a vast variety of environments through time, becoming far and away the most diverse group of animals to ever live.

The poem shows us just a bit of this diversity, flashing forward to the future inhabited by two “descendants” of Paradoxus, Lepidocaris and Arthropleura, who talk with each other about their very different adaptations and environments. Lepidocaris was a type of small crustacean, well-adapted to living in the ocean with long legs that could be used to swim and run quickly underwater. It is notably one of the first freshwater crustaceans. Arthropleura was a very different animal, an up to 8 foot (2.5m) millipede-like arthropod that lived on land that mostly ate plants in the humid, warm forests of the Carboniferous period. At the time Arthropleura was the largest land animal and is a front runner for the largest arthropod to have ever lived, and its fossils and fossil trackways can be found in rocks in Canada, the U.S.A. and Europe.

Trilobiography of Walter Garstang

Walter Garstang (1868–1949) was a radical thinker in the field of developmental biology, however his “irrepressible sense of fun caused him to present his views in lighthearted verse.” Some of his ideas were not taken seriously in his time because they were so counter to the status quo and so theoretical that people thought he was joking.

He was most famous in his lifetime for opposing the “theory of recapitulation,” which was widely accepted in developmental biology at the time. The theory, developed by Ernst Haeckel, states that as an embryo develops it goes through stages that resemble its evolutionary pathway. For example, a bird embryo would go through stages resembling an invertebrate, fish, reptile, and theropod dinosaur before developing into a baby bird. This hypothesis has now been discredited but was widely accepted at the time. Walter argued instead that invertebrate larvae were not intermediate forms showing an evolutionary pathway but were in fact adapted to their environments just like adult forms. Walter also suggested that chordates (animals possessing a spinal chord) evolved from the larvae of another group, possibly from the sister group to Chordata, Ambulacraria, which includes animals like sea stars and acorn worms.

These theories, alongside other hot topics in invertebrate biology from the early 1900s, are detailed in his book of poetry Larval Forms and Other Zoological Verses. Walter was known for using humour and verse when discussing scientific topics, but the poems are almost painfully accurate. Full of jargon, and bookended by dense explanations of larval development, the book would be daunting for a layperson, but holds a special place in the hearts of other invertebrate zoologists.

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