Flatfish Metamorphosis

Pity the flounder! Pity, I beg thee…

Adolescence is difficult. Puberty is an awkward transitional time when the winsome cuteness of childhood departs forever but is not fully replaced by the graceful strength and confidence of adulthood. But before you have a PTS flashback to those rough years, spare a moment of pity for the poor flounder. Flounders (and other flatfish like halibuts, soles, and flattest of them all, turbots) are born…err hatched like us with two eyes on either side of their skull. As tiny transparent larvae living among the zooplankton, flounder fry can see a panoramic view of the ocean so as to better evade predators. As they dart through three dimensions, their bilateral symmetry is like that of the rest of the vertebrates.

As searingly depicted in this stunning diagram

Then, as they grow into adult fish, a strange and remarkable metamorphosis occurs. Bones in the flounder’s skull distort and one eye migrates across its head so that both eyes are on one side of its face. Imagine if your left eye traveled over the bridge of your nose to permanently join your right eye on the right side of your face!

An adolescent flatfish–the eyes are just beginning to creep to one side (photo for PBS Nova)

Of course eye migration is but one aspect of the flounder’s change to adulthood. The fish begin to swim at an angle. One side of their body becomes flecked with color while the other becomes white (the better to merge into the two dimensional world of the bottom). Speaking of color, the once transparent fry becomes opaque! Their mouth opens on one side of their head and they must learn to swim like a flying carpet.

But don’t let their remarkable transition and their comic appearance deceive you. The flatfish are extraordinary predators and they are also geniuses at avoiding the many toothy hunters of the ocean. Their close set eyes protrude above the sand and see unwary prey with acuity and laser focus. Fossil finds from Monte Bolca, a beautifully preserved Eocene coral reef, show that the flatfish were evolving into their current form 45 million years ago (as the primates were taking to the trees, the bats were first taking wing, and the little dawn horses were scampering through the endless tropical groves). For at least 45 million years the flatfish (which, I should have mentioned, constitute the order Pleuronectiformes) have been camouflaged at the bottom of the sea feasting on shrimp and minnows while the world blinked and didn’t notice them. They are still out there thriving, even as whole parts of the ocean ecosystem collapse. It is a striking reminder that wrenching changes can work out for the best!

An adult Turbot

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Myrmidons

In the Iliad, the great Greek epic of ferocity, loyalty, and war, the Myrmidons were the most ferocious and loyal of all of the various Achaean warriors.  The myth of how the Myrmidons came into existence reveals the source of their bravery, strength, and discipline as infantry troops.   The story combines literature, invaders (for the Myrmidons were ever attacking), and…hymenopterans.

Creation of the Myrmidons (artist unknown)

As with so many other Greek myths, the story starts with the philandering of Zeus, who fell in love with Aegina, who was the eponymous nymph/goddess of Aegina—an island which is located in the Saronic gulf between Attica and Argolis.  According to the writer Hesiod (and later Ovid) Zeus appeared to the nymph as an eagle and loved her.  From their union came the demi-god, Aeacus, born as king over the island.  Hera, jealous as ever, punished the inhabitants of the island for Zeus’ affairs by sending a plague (or possibly a dragon) to destroy them all except for the immortal Aeacus.  Devastated by the deaths of his subjects, the lonely Aecus prayed to Zeus to repopulate the island.  The king of the gods heard the prayer and responded by transforming a colony of ants in an oak tree into men and women.  These new people were tough, warlike, and hive-minded—just like the ants they originated from.  Aeacus eventually wearied of kingship and turned the throne over to his son Peleus (one of the heroes of the ill-fated Caledonian boar hunt) who eventually wed the sea-nymph Thetis.

The creation of the Myrmidons

There is another (possibly older) myth which is more troubling.  In this alternate story, Zeus transformed himself into an ant in order to seduce Eurymedusa, the daughter of a river god.  She bore a son, Myrmidon, and the antlike Myrmidons all descended from him. I think I prefer Ovid & Hesiod’s version of the story!

Myrmidons (Tristan Schane, oil on illustration board)

Of course, in accordance with the universal law of disparity between intention and result, the Myrmidons (who enjoyed war more than the other Greek armies) ended up sitting out most of the battles mentioned in the Iliad due to the feud between Achilles and Agamemnon—but their ferocity was well-documented in Greek letters.  A passage from the end of the Iliad describes how excited the Myrmidons became when Achilles finally freed them to join the battle after holding them back while other men fought:

Meanwhile Achilles made his round of the huts and called all the Myrmidons to arms. They gathered like a pack of ravening wolves filled with indescribable fury, like mountain wolves that have brought down a stag with full antlers, and rend it with blood-stained jaws then go in a mass to drink, lapping the dark water with slender tongues, dripping blood and gore, the hearts in their chests beating strong and their bellies gorged. (Iliad, Book XVI, translated by A. S. Kline)

The popularity of the Iliad has meant that the Myrmidons were not forgotten: the word has become part of the English lexicon where it means a completely devoted warrior-minion.

The Naming of Turkeys and the Death of Meleager

Before Thanksgiving, I posted a column about the confusing circumstances behind the names of turkeys. It turns out that the noble birds derive both their English and taxonomical names from being mistakenly identified as guinea fowl.  What I failed to explain in that column was how guinea fowl came by their scientific name “Meleagrides” which in turn became the genus name for American turkeys (Meleagris).

So where did guinea fowls get their name?  According to The Metamorphosis by Ovid, after Althaea, the Queen of Calydon, burned a magical log and thereby killed her son Meleager–an act which was bitter revenge for Mealeager killing another of her sons along with her brother in an intoxicated fight–she understandably became unhinged with grief (all of this is related in yesterday’s post if you are having trouble keeping up with the mayhem). Althaea then killed herself, leaving her daughters to cope with a complete family catastrophe.  Their distraught lamentation was so absolute and cacophonous that Artemis pitied them and transformed them into guinea fowl–which became sacred to her.  Of Meleager’s sisters, only Gorge and Deianara (who had their own sad destinies to pursue) were spared this fate.

Death of Meleager (Roman, 2nd century AD, marble)

So it turns out that turkeys are ultimately named after a heroic Greek spearman who was tragically destroyed by a bitter twist of fate after a drunken brawl (or by the wrath of Artemis, depending on how you look at mythological causality).  The paths of fate are strange indeed.