by Noah Schlottman '16
Sometimes, there seems to be an endless supply of readings, homework, lab reports, and projects. If you’re ever in a slump because of the demands of school and those sixteen student groups you’re involved in, at least there’s one thing you’ll never have to worry about: being eaten.
Eating and being eaten are the two biggest problems for pretty much every other organism on the planet. What’s worse is when whatever is eating you is also eating your food. Welcome to the life of a caterpillar.
In the Western Sahara, years can go by without precipitation of any sort. When it actually does rain, there is a subsequent abundance of caterpillars in the Acacia trees that thrive in this arid ecosystem. The camels raised by the nomadic Sahrawi pastoralists in Northwest Africa then eat the caterpillars’ food (the acacia leaves) and, at the same time, unknowingly consume the caterpillars themselves. So how do these caterpillars compete with these significantly larger camels not only for food, but also for their very existence?
The Sahrawi peoples have noticed that after their camels eat these caterpillar-topped Acacia leaves, the pregnant dromedaries either have sudden abortions or give birth to weak, sickly, and sometimes premature calves. The Sahrawi call this phenomenon duda, the common Arabic term for ‘worm’ or ‘caterpillar.’
Not only have the Sahrawi and other pastoralists in Northwest Africa (the Moors of Mauritania and Tuareg of Niger) noticed the drastic effects of caterpillar consumption in camels, but also this phenomenon has been observed in horses in the Western world (1).
Mare Reproductive Loss Syndrome (MRLS) was first observed in Kentucky in the spring of 2001. A subsequent investigation discovered a link between the high abundance of caterpillars and numerous abortions and birthing of weak foals in mares. Since then, caterpillar consumption has been shown to affect many different types of livestock by impairing the reproduction and propagation of healthy offspring.
All in all, the natural world is a ruthless one, and both duda and MRLS are hypothesized to be adaptations by which certain genera of caterpillars can compete for resources against, admittedly, much larger foes. Though the mechanisms of these phenomena have yet to be unraveled, they are undeniably effective in impacting populations of animals that compete with these caterpillars for food. And when it comes to being unintentionally consumed by camels, well, that’s just how some caterpillars get over the hump.