Home and colonial

Bryozoans are colonies of individual aquatic, tentacle-waving animals (zooids), each of which asexually buds from its parent and builds its own cell of calcium carbonate on the parental one. Alternatively, new colonies can be started after eggs and sperm are released. Predators have various unseemly ways of extracting the juicy bits of individual zooids, but the sheer size and reproduction rate of an established colony means it can generally carry on. A zooid explains:

In a pretty bryozoan
I live quietly on my oan;
But there’s safety in big numbers; so you’ll find
Our colonial empires
Filled with owner-occupiers
Of the tentacled, suspension-feeding kind.

We don’t have to find a mate;
We just bud to propagate,
Though occasionally we have a go at sex.
(It’s well worth the extra labours
To escape from all the neighbours,
Who can sometimes feel like millstones round your necks.)

Not many folk collect us
And geologists reject us,
Yet sometimes it’s a job to stay alive.
We get ‘drilled’, and sucked, and grazed,
But we zooids are not fazed:
“The colony is all – it will survive”.

[Image: micrographia.com]
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