One tiny sea snail acts as a flying insect under water as per the findings of new research published in the Journal of Experimental Biology. The sea snail, part of the sea zooplankton is known as Limacina helicina.
At first sight, it looks just like a snail. A more careful observation will reveal the sea snail’s wings, developed in the exact pattern as those of a butterfly. According to Doctor David Murphy, lead author of the study, the Limacina helicina could well be regarded as an underwater butterfly.
The 3mm snail uses its wings for underwater motion, combining the vortex-type of motion characteristic to winged insects to cut through the water.
The scientific team behind the study, led by Doctor David Murphy used flow-tracking systems and high-speed cameras to reveal more about the marine snail. Limacina helicina was known to scientists for a while. However, the sea snail’s exact structure remained a mystery until now. The wing-like structures that brought the flying insect simile develop where a snail’s foot would normally be found.
The data collected in the study has revealed that the winged sea snail is in fact a predatory mollusk. Albeit tiny, it feeds on plankton even smaller than its own size. To be able to catch its prey, Limacina helicina spreads out an elaborate mucus net. Typically, all organisms in the zooplankton are known to use whatever swimming appendage they are endowed with as paddles that help motion.
Doctor Murphy expected the tiny sea snail to be similar with its zooplankton fellows. However, this wasn’t the case. The fact that one tiny sea snail acts as a flying insect under water came as a surprise. The wing-like structures and their function were revealed thanks to tomographic particle image velocimetry.
This methodology implies four high-speed camera being calibrated with a tiny volume of fluid lighted by laser beams. The flow-tracking system is trained thanks to the glimmering particles in the fluid. Doctor Murphy explained:
“Using our four cameras, we make a 3D measurement of the flow that the animal produces as it’s swimming”.
The fragile sea snail was difficult to study otherwise. In the sub-Arctic and Arctic waters where it can be found, its movement and wing-like structures are difficult to observe. Thus, under laboratory conditions, the research team could take a better look at the flow of water around the winged sea snail.
The vortex-type of motion characteristic to flying insects serves Limacina helicina the same purpose: generating lift. The tiny sea snail flaps its wings behind and rapidly pulls them apart afterwards. If you’ve ever watched a slow-motion footage of a butterfly’s flight, the motion is strikingly similar.
Photo Credits: Wikimedia