Ostracods are generally rare at Smokejacks, the clay pit at Ockley, Surrey. But Dr. David Horne discovered a very localized assemblage of these microscopic bivalve crustaceans there, close to where Iguanodon bones had been found. He concluded that the area had been a ‘temporary pond’ on what is now an area of Weald Clay, and that the dinosaur’s decay had enriched the water to the extent that algae flourished. The ostracods probably arrived by air as desiccation-proof eggs on or in the bodies of migrating birds such as Arctic terns. The Cyprididae group of ostracods use various means of reproduction, including parthenogenesis, as one of the fossilised travellers explains.
A migratory tern
Carried me on his stern
As an egg, on his northward migration.
I didn’t feel well off
When at Smokejacks I fell off –
It caused me some great consternation.
For I’d not, as a rule,
Choose a temporary pool
To grow from an egg and to breed.
But an ostracod saying
Is: “A dino, decaying,
Makes a soup in which algae succeed”.
And at Smokejacks, I found
On its wet, clayey ground,
Where Iguanodon had slumped to his doom,
That the pool where he lay
In his mortified way
Was alive with a green algal bloom.
Now algae are food
For an ostracod brood,
So that saying turned out to be wise.
With my cells rehydrating,
I think about mating,
But where are the ostracod guys?
What few there have been
I think were last seen
In South Africa’s warm ecosphere,
So with no men about
I’ll manage without –
No sex, please, we’re ostracods here!