Walking Fishes

Bichirs, eels, and climbing perches,
Sometimes swim and sometimes crawl –
See their wriggles, flops, and lurches,
Up up out of the water all.
Like lobe-fins did so long ago,
They make a hopeful bid to leap and grow.
Distant species such as these,
Who gulp the breezing air with ease –
Distant species, all who please
To give the land a go.

But why do gobies only skip the mud of late,
And not before ?
Just what has changed to make it worth the risk to skate
Upon the shore,
And dip their ray-finned toes upon the sands of fate
Once more ?
For surely, this cannot be new –
This must be something that they do
Since days of dinosaur.

I guess that they were out-competed,
Couldn’t play the odds –
I guess they found the land replete
With hungry tetrapods.
So why did they think they ought to ?
Small fish from a big pond,
Who sought beyond for everlasting worms,
And spurned the nice-yet-dull –
These fishes-out-of-water,
Inventing bicycles.

Mudskippers diverged from the other gobies around 140 million years ago, or at around the time of the American Civil War according to this method.  Of course, that doesn’t mean that their particular lineage of goby started venturing out of the water until much later, though I cannot find any details as to when this first happened.