Colorful Image Lights Up Microscopic Guts of ‘Water Bear’

Tardigrades—eight-legged, microscopic “water bears” known for surviving in extreme conditions—can be pretty photogenic, given the right lighting. Last month, an image of a tardigrade’s insides lit up by fluorescent stains was named an Olympus “Global Image of the Year” award winner for 2019, reports Mindy Weisberger for Live Science.

Biologist Tagide deCarvalho, manager of the Keith Porter Imaging Facility at the University of Maryland Baltimore County (UMBC), created the award-winning photo of the microscopic animal, the University announced in a statement. Since tardigrades are mostly colorless, deCarvalho used fluorescent dye molecules to stain the tardigrade’s internal structures, revealing an eye-popping look inside a creature that typically grows no longer than one millimeter in length.

“I knew the moment I saw this colorful specimen that it was going to be a remarkable image,” deCarvalho says in a statement. “I love sharing the fascinating things I see in the microscope with other people.”

Tardigrades, also known as “moss piglets,” have earned a bit of a cult status over the years for being difficult to kill and “endearingly tubby,” reports Weisberger. In 2012, Smithsonian magazine reported that while the water bears generally live on moist pieces of moss or in the sediment on the bottom of lakes, they can also survive at both 212 degrees Fahrenheit and 459 degrees below zero. They’ve also been found enduring intense pressure at the bottom of the ocean floor.

To protect themselves, the animals curl their bodies into a compact pill shape, become completely dehydrated and secrete chemicals that form a protective shell called a tun. This process, known as “vitrification,” effectively mummifies the animal and allows it to survive even in outer space, reports Brian Resnick for Vox.

As Jenny O’Grady writes for UMBC Magazine, deCarvalho calls the specialized process of creating microscopic images with fluorescent molecules “Sci-Art.”

“I’m able to produce so much color in my images by using multiple fluorescent stains and capitalizing on the natural fluorescence of the samples,” deCarvalho says in a statement. “I’m excited about this image because the fluorescent dyes I used allow you to see the tardigrade digestive tract, including the mouthparts and stomach filled with food.”

Her image earned first place in the Americans region of the Olympus Global Life Science Light Microscopy contest, which “aim[s] to celebrate both the artistic and scientific value of microscopy images,” per a statement. The top pick for Global Image of the Year went to a brightly colored image of a slice of mouse’s brain, created by Ainara Pintor, a doctoral candidate at the Basque Center for Biophysics in Spain.

Nora McGreevy | | READ MORE

Nora McGreevy is a former daily correspondent for Smithsonian. She is also a freelance journalist based in Chicago whose work has appeared in Wired, Washingtonian, the Boston Globe, South Bend Tribune, the New York Times and more.