Scientists Reveal Biomechanics of How Marine Snail Larvae Swim

Scientists have recently discovered the biomechanics behind how Marine snail larvae swim. This is particularly important as the larvae's swim patterns hold a key behavior that determines their dispersal and ultimately, their survival. 

Researchers from the Woods Hole Oceanographic Institution (WHOI) and Stony Brook University grew Atlantic limpet larvae that's slightly larger than a grain of sand, and recorded a microscopic video of them swimming. As previous studies have shown that the larvae swim fast as they beat hair-like cilia, this new microscopic video and research shows something different.

"I was actually quite surprised when I saw there was no relationship between cilia beat frequency and how fast they swim," Karen Chan said, a WHOI postdoctoral scholar and the lead study author, via a press release.

Though the larvae control the speed of their swim patterns, they subtly shift the position of their velar lobes, which are flat, disc-shaped wings fringed with cilia.

"Collaborations between organismal biologists such as myself and oceanographers, who develop and use such clever  technology, is helping us find answers to important questions that would otherwise be impossible," said co study author, Diana Padilla from Stony Brook University's Department of Ecology and Evolution, who collected the abundant study species from the North Shore of Long Island, N.Y., for the research, via the release. She also grew the larvae in her lab that is shown in the WHOI video analysis.

Associate scientists at WHOI and collaborator on the project, Houshuo Jiang, notes that the research team's ultimate goal is to better understand how the limpet plays a role in shaping the marine ecosystem, environment and climate change.

Jiang built a customized, vertically oriented optical system that can magnify and record high-speed, high-resolution video of microorganisms that freely swim in a vessel of seawater at 2,000 frames per second.

"Much more can be observed in great detail using this setup than observing under a microscope," Jiang said, via the release.

Though scientists have traditionally been able to trace the speed of larvae by placing a piece of transparency on a computer screen and tracing and counting the cilia beats by hand, this method is much more advanced and easier to record.

The high-resolution video can also alter bright and dark light as the cilia beat up and down.

"This is a way to apply a new technique to address this old problem."

Jiang studied the swimming larvae from when they were two days old to 19 days old. She found that within a single day, their speed could vary from swimming one body length per second to four body lengths per second.

The flexibility of these creatures' ability to control their body speed helps make them to be so successful in life.

More information regarding the study can be found via the journal PLOS One.