Caterpillars — Masters of Domination

Evolution does strange and wondrous things — like creating Caterpillars Masters of Domination!

I’m proof of how little we know of nature’s complexity and how much we misidentify actions through our limited knowledge… 

I always thought the most amazing thing about caterpillars, besides their massive appetite and rapid growth, was their ability to transform themselves from puffy/fluffy plant eaters into delicately winged nectar sippers.   Even then, we tend to credit this magical/inspirational transformation more to the butterfly for emerging in such a graceful state than to the caterpillar for doing all the hard work.

So I was kind of shocked to learn that in the war of survival the seemingly benign and vulnerable caterpillars can be dark masters of domination.   Recent research is showing that at least some of these puffy marauders manage to up their survival odds considerably through the use of deception, mind control and infiltration.   And yet, as I found out in my own garden, one tiny enemy can turn the tables on them.

So here’s some survival tips I’ve recently learned through Caterpillars.

Be wary of sweet nectar and those who produce it

The Japanese Oakblue Butterfly caterpillar is able to produce an addictive, dopamine type nectar that has mind controlling properties.

When eaten by ants, this special caterpillar nectar alters the ants’ behavior to such a degree that they abandon their queen and fellow ants to become bodyguards to the caterpillar.  So enslaved by the nectar’s drug the ants even become aggressive and attack on command of the caterpillar.

From Daily Mail:

“Scientists had believed the ants protected the caterpillars in exchange for the nutrition they were getting from the sugary section produced by the butterfly larvae. In fact the solution contains drugs that alter the brains of the ants so that they will treat the caterpillar like a member of the colony and defend it.”

Be wary of those who tell you what you want to hear

Least you think the caterpillar of the Oakblue butterfly is a fluke of nature, the Large Blue caterpillar uses both chemicals and sound to make bodyguards and baby sitters of ants while feasting on the ants’ young.  As Scientific American shares:

“They [Large Blue caterpillars] are also able to mimic the sounds of the ant larvae, and secrete chemicals that make the ants believe that the caterpillar is one of their offspring. As a consequence, the ants will carry the caterpillars back into their nest. … where it is protected from predators, occasionally venturing into the centre of the nest to feast on ant larvae. It is also able to mimic the sound of the queen ant to prevent it being detected.”

And apparently it takes multiple communities of ants to feed and care for one growing caterpillar.

“Research indicates that 230 large larvae and a minimum of 354 Myrmica workers are needed to ensure the survival of one Large Blue butterfly! As these are far more than will be found in one nest, it’s likely that the caterpillar can move between ant nests, surviving starvation as it travels. “

And, lest you think caterpillars have all the answers in the survival wars.

Be wary of tiny enemies capable of producing an army

When I found a very large, Tobacco Hornworm caterpillar strip mining a tomato plant in my own garden last month, I decided to do a field test of sorts.

My usual I-can’t-kill-it-but-it-needs-to-go form pest control would be to toss the caterpillar into the Azalea bushes in the hopes that something (bird, lizard, ?) would eat it before it made its way back to the plant.

This time I would let nature take its course and see if anything interesting happened.  (Not a difficult decision to make in the name of science as it was the end of the season and the plant under attack hadn’t been particularly good producer.)

Over the next couple of days, the caterpillar ate and ate.  It devoured all the leaves and tender branches and then moved on to the last tomato.

No minions, ants or otherwise, in sight.  Not that any were expected, exactly, but still…

Two rainy days later — Still no ants, but things had taken a dramatic turn.  I found the caterpillar upside down with 30 or more tiny pods hanging from it:

Next day — fewer pods and it looks like it’s been sucked dry.

The day after that — almost no pods left.

So what happened?  Where did the pods come from?  Where did they go?

It seems a tiny parasitic wasp (Cotesia congregatus) with one heck of a stinger was the culprit…

This time lapse video shows it best:

And the cycle of use and abuse doesn’t end there… even the parasitic wasp larval are in turn used as hosts by hyperparasitoid wasps.

###