Beautiful lacy wreath? Or killer fungus?
The scientific truth is not immediately apparent in a startling image of the leg of a tick presented by Palma Catravas and Kathleen LoGiudice of the Electrical Engineering and Biology departments, using Union’s scanning electron microscope (SEM).
The image was selected as a semifinalist in the 2008 International Science and Engineering Visualization Challenge, sponsored by the National Science Foundation and the journal Science in the Photographs/Pictures category.
Their entry, “A Parasite Engulfed,” provides an unusual view of the black-legged tick, or Ixodes scapularis, being consumed by a fungus.
In a description accompanying the image, the collaborators wrote, “The somewhat sinister looking leg of this tick is unexpectedly adorned by what appears to be a beautiful lacy wreath. Upon closer observation, however, it becomes clear that the seemingly innocuous lace is the aggressor, a fungus that has apparently killed the tick and now shrouds it in death.”
The image is of particular interest to entomologists and disease ecologists who are looking at certain fungi as possible biological agents that may control populations of ticks that cause Lyme disease. Such imaging also could help biologists learn more about how the fungus kills the tick.
“I love the art-science connection – the idea of using microscopy tools not only as part of research or inquiry, but from the artistic side, as well,” Catravas mused.
In setting up the image, Catravas and LoGiudice found that the visual character of material changed substantially with magnification.
“With the tick magnified beyond identification, the image spoke of lilting grace,” she said. “By contrast, low magnification images turned macabre, with the tick often enveloped in a thick mat of tangled hyphae.”
The SEM is used to acquire high resolution images using an electron beam instead of light. The College purchased the state-of-the-art instrument after receiving an NSF award of nearly $300,000 last year.
Another SEM image by Catravas and LoGiudice, also of a tick (not ensnared in fungus) appears in the photo gallery of the October 2008 issue of the Bulletin of the Ecological Society of America.
The two began collaborating via a course Catravas co-teaches with Michael Hagerman (Chemistry) and Brian Cohen (Biology), titled Frontiers of Nanotechnology, in which the students receive hands-on experience with microscopy tools.
“We’re working on incorporating the SEM into the course rather than simply exploring theoretically how it works,” Catravas said. “For that you need exciting samples, and Kathleen’s ticks are some of the best teaching samples.”