I recently wrote a story for American Scientist about the evolutionary biology of rhinoceros beetle horns and recent research by Erin McCullough, who is currently at University of Montana. I love field stories, and she had some good ones. Field biologists end up doing the quirkiest, most random things; the job often demands of us tasks that your average office worker would find phenomenally uncomfortable and unmanageable. Here are McCullough’s field reflections that did not fit into the American Scientist report:
“Rhinoceros beetles are amazing creatures—they have some of the most fantastic weapons morphology that you find in nature. But we actually don’t know a lot about their behavior in the field because, one, they’re nocturnal, which makes them tricky to study; and, two, a lot of the species feed high up in tree canopies or in burrows, which makes them also not very ideal for field experiments. The species that I study, Trypoxylus dichotomus, is nice because in certain areas, if you find a good patch of their host plant, they can be quite abundant. They feed on ash trees, which aren’t super high, so you can actually see the beetles. The first time that I saw the beetles fighting in the trees, there was just like this childish surreal feeling, like ‘Oh, my beetles are fighting!’
Still, they’re nocturnal, so that can be super tiring. The life cycle’s about a year for Trypoxylus. The adults come out in the summer. From about June to August, they feed on the sap of trees, they mate, the females oviposit into the soil, the larvae feed on soil and humus. They’re larvae for I guess seven, eight months or so, they overwinter, they pupate, and then they’re adults during the summer. All summer long from about 6 PM to about 6 AM, I was chasing beetles. I mean it’s fun, but at 2 o’clock in the morning, you don’t love your project.
The beetles’ horns aren’t dangerous to us. They don’t bite or sting. But they have claws, which has to do with the fact that they have to hold on really strongly to the trees. When I would take them off their tree and their female for measuring, they clawed onto me pretty tightly. The first week or so of my fieldwork, I was just working with bare hands. And my hands just got ripped to shreds. I learned that I needed to use leather gardening gloves so that the beetles wouldn’t totally tear my skin apart, and the gloves also kept the mosquitoes off my hands. I wore gardening gloves, long-sleeve shirts with a collar—I looked sort of ridiculous. I had this huge backpack with all of my radio telemetry equipment, my radar gun, a video camera so I could film the beetles. And a tripod. And a headlamp. I looked crazy, like a totally crazy beetle biologist. It would be fine if I worked at a field station, but the fact that I was at a university in Taiwan, people thought I was crazy. Oh, and I don’t actually speak Chinese. In Taiwan, it was sort of tricky getting around. I could say numbers and so I could get in to the market. But Chinese is a tonal language, and some of the subtleties are lost on me. And the term for rhinoceros beetle in Chinese sounds a lot like the terms used to ask how much something cost at the market. I was probably just going around saying “Beetles! Beetles!” Which is why I got a lot of strange looks from people in the markets.
The beetles are super-charismatic, and I love ‘em, even if they are frustrating and I spend a lot of time watching them do nothing.”