A Day in the Life of a Field Biologist: The Itch-and-Scratch Complex

close up of mosquito sucking...
close up of mosquito sucking...

"We hope that, when the insects take over the world, they will remember with gratitude how we took them along on all our picnics."
--Bill Vaughan

I love insects, which is probably why I became a scientist, focusing on these extraordinary critters and their relationships with plants in the forest canopy. But insects also love me -- and a recent research trip to Ethiopia proved no exception. After one short hour traipsing through tiny fragments of vegetation called church forests, I walked away with 26 chigger bites. (To note, my Ethiopian colleague had zero!)

Chiggers adore me. Although they didn't bite immediately, I was anything but safe. True to their behavior, the creatures prowled my skin until they found all the cozy spots: clothing lines, skin creases, and other hotspots. Even worse, a colleague who studied chiggers had the audacity to inform me that each one can bite multiple times. So I had cultivated a small tribe that was now poised to exploit my exterior. Indeed, my new residents provided three nights of what felt like torture. They behaved as night owls, inflicting the majority of bites in the darkness of my bedcovers. I lay in bed for hours, acknowledging the necessity of a do-not-scratch-at-any-cost martyrdom, but suffering tremendously from the unbearable itch factor.

The only mild relief would have come from wearing very little clothing, which was certainly not possible as a visiting Fulbright scholar and also a minority scientist at Jimma University, Ethiopia. (The proportion of Caucasians on this campus was fewer than 1 percent, and women faculty only slightly higher.) So I discretely scratched my way through meetings with the University vice president, provost, faculty, and students and multiple seminar presentations. My tube of cortisone cream was long gone, but the love and affection of my chigger population stayed with me throughout my time in Ethiopia. "Adorable!" my entomology colleagues would exclaim.

Not surprisingly, on the topic of challenging insects a field biologist might encounter, chiggers are relatively benign. There's a long list of notable tropical creatures that enjoy human substrates. The candiru, or vampire fish, for example, is a parasitic catfish native to the Amazon Basin. Legend has it that these sneaky critters infect male body parts while their unsuspecting hosts are swimming in neotropical rivers; its sharp, toothed protrusions allow it to enter the urethra but not easily exit.

Perhaps the most notorious insect in the tropics is the "botfly," an aggressive member of the insect order Diptera known for laying a single egg under the skin of its victims. When a larva hatches, it lives off of the host's flesh for several weeks, wriggling painfully under the skin before finally emerging as an adult. The human host has two choices: let the creature develop and escape via natural means, which requires unlimited self-control, or use one of many experimental methods to try to coax the juvenile out.

Like the chiggers, these pests are typically not life-threatening, just obnoxious. The true threats are insects that carry infectious diseases -- mosquitoes that transmit malaria and dengue fever, for example, and the insect vectors of diseases such as river blindness and leishmaniasis. Despite this, my African colleagues are amazed that we American scientists dare to work amidst grizzly bears or rattle snakes. And they are terrified of getting a tick bite in America that might bestow Lyme disease, so I guess we all have our anxieties about working in remote regions as field biologists.

Why, then, do those of us who conduct research in the tropics still love working there? It's not for those obnoxious insects, believe me. Instead, it's their millions of close cousins representing unknown species, any of which might carry chemicals that cure diseases, or serve any number of other economically or ecologically important functions. If we can better understand the complexities of biodiversity, then the chance of survival for all Earth's life forms will certainly grow. So, for the sake of my kids, I will endure a few more chigger bites -- and hopefully contribute a few threads of knowledge that will contribute to the sustainability of life on Earth.