A novel invention described in a study published in the journal Current Biology has developed a method for collecting soft-bodied deep-sea jellyfish to avoid causing unnecessary distress when studying them. Using “soft robotic linguine fingers” the new tech has been found to cause significantly less stress to the captured jellies.
Identifying when a jellyfish is in distress is a complex task. Unlike terrestrial animals they don’t cry or howl if they’re in discomfort, and, so far as we know, they unfortunately don’t use their tentacles to express themselves. So how do you measure the happiness of jellies?
"Imagine you're sitting very happily at your desk and I take a measurement of what genes are active, and then I poke you with a claw hand,” said senior author David Gruber, professor of biology at Baruch College, City University of New York, in a statement. “I'd then look at how differently your genes reacted compared to when you were sitting unbothered; the strength of that difference can act as an indicator of your level of stress."
An analysis of the genes expressed by the jellyfish when they were swimming freely, held by the soft robot fingers, or gripped by the more standard rigid claw was carried out. The team found that jellyfish held by the ultra-soft noodle-inspired fingers expressed significantly fewer stress-related genes than when clutched by the traditional submersible grippers. Jellies in the clutches of the claw also began to express “repair” genes implying they were anticipating pain and physical damage. In a highly relatable statement, Gruber explained, “they immediately go into self-repair/stress because – being such a fragile organism – being stressed out is quite common for them."
But the impacts of this study extend far beyond just jellyfish. "We just used them as our sample organisms," says Gruber. "Now that we've shown this method can cause less stress to something as fragile as a jellyfish, it really proves our hypothesis that soft robots in the deep sea can be effective tools for all manner of delicate interactions."
The applications for this softly-softly approach also extend far beyond shepherding jellyfish, with Gruber hypothesizing the same technique will see beneficial effects for all manor of gelatinous deep-sea organisms. The researchers also go on to describe a number of terrestrial tasks that could stand to benefit from the flexible but tough and lightweight tools, such as harvesting fragile fruits without causing the tears and bruises associated with grabbers.
The trying conditions of ocean environments have historically called for tough equipment and brutal practices, tearing up oceans floors and killing specimens to be studied at the surface. But the shift towards gentler tools and techniques is allowing researchers to gather real-time data on deep-sea organisms, carrying out medical checkups and even taking DNA swabs while causing little physical or environmental impact. Robots like this noodle-fingered jelly grabber mark a new era in marine biology dedicated to the collection of ecological data in an ecologically kinder, less invasive manner.
"By integrating soft robots into how we conduct research of the deep sea, we are reshaping our vision of the future for marine biologists," said Gruber. "It's our philosophy that we should be as gentle and careful as possible as we study and approach these new frontiers."
Ever wondered what a jellyfish sting looks like under a microscope?
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