Brush Me, Barnacle
These barnacle legs look like a brush that might be used by a chimney sweep. Often attached to ships, barnacles use their hairy legs to comb through the water to collect organisms, mostly microscopic invertebrates, to eat.
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DownloadBrush Me, Barnacle
These barnacle legs look like a brush that might be used by a chimney sweep. Often attached to ships, barnacles use their hairy legs to comb through the water to collect organisms, mostly microscopic invertebrates, to eat.
What am I looking at?
Here we see the legs of a barnacle (1) extended out from its body (2) to find and catch food in the surrounding water. The colors are a combination of autofluorescence (colors generated when a laser shines on a sample) and of the red and blue fluorescence of Congo red and Calcofluor white biological dyes.
Biology in the background
Under the waters of the Chesapeake Bay, this barnacle eats using its legs, which are lined with hair-like bristles. Adult barnacles are sessile – meaning they live sedentary lives, attached to rocks or other surfaces in shallow waters. They send out these specialized, retractable appendages from an opening at the top of their shell to rake through the water for microscopic organisms and other food particles.
After sifting the water for food, a barnacle moves the captured food toward its mouth, which is inside its shell. Since adult barnacles live stationary lives in shallow marine (saltwater) environments, when the tide goes out, a barnacle stays inside its protective outer shell. Then when the tide comes in, it’s feeding time, and the barnacle’s legs extend to once again rake the water for food.
This barnacle is about 3 millimeters long, or roughly eight times smaller than the width of a human thumbnail.
Technique
This image was taken using confocal microscopy.
Igor Siwanowicz, Howard Hughes Medical Institute, Janelia Research Campus