Gently does it
Soft robotic fingers lift jellyfish without stress.
CREDIT: Jason Jaacks
Soft robots have many uses, and now we can add lifting jellyfish to that list.
US researchers have shown that capturing jellyfish – in this case the common Aurelia aurita – with what are described as soft, linguine-like fingers is much less stressful for all concerned.
In fact, they report in the journal Current Biology, the jellyfish display gene expression patterns similar to free-swimming jellyfish, demonstrating their calm response to capture.
In contrast, those caught by a traditional claw expressed repair genes at higher levels compared to the free-swimming or gently held jellyfish, suggesting they were priming themselves for physical harm.
"I think what was interesting is that when you start harassing them with standard grippers, they immediately go into self-repair/stress because, being such a fragile organism, being stressed out is quite common for them," says senior author David Gruber, from The City University of New York.
Gene expression is the key here because, unlike a cat or a dog, a jellyfish can’t hiss or whine to show it is stressed or in discomfort.
"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, says Gruber.
“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.”
What’s really important, of course, is the bigger picture.
In the past, collecting data from the ocean has required pulling material from the seafloor or killing specimens to then study on the surface. However, with advances in soft robotics, it’s now possible to take swabs of DNA or even conduct medical check-ups on deep-sea creatures in real-time with little physical impact.
"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,” says Gruber.