Menu

Stressed Shore Crabs

Electrical shocks cause a physiological stress response in invertebrates previously thought incapable of feeling pain.

Nov 12, 2015
Karen Zusi

FLICKR, JOHN HASLAM

Invertebrates will respond to certain dangerous stimuli by trying to escape, but these animals lack the brain regions associated with the sensation of pain in vertebrates. As a result, some scientists have assumed that invertebrates can’t sense pain in the same way that vertebrates do. Yesterday (November 11), a pair of UK-based researchers published results in Biology Letters that potentially upend this perspective.

In a 2014 Animal Behaviour paper, researchers from Canada and the U.K. offered a set of criteria to determine whether an animal is experiencing pain, including learned avoidance behavior and measurable responses in physiology. Robert Elwood, an animal behavior researcher from Queen’s University Belfast, had previously shown that invertebrates can learn to avoid electrical shocks, but had not linked this observation to the animals’ physiological responses.

With colleague Laura Adams, Elwood tested these criteria using a set of 40 European shore crabs (Carcinus maenas) collected from Northern Ireland. The pair shocked half of the crabs in the right and left legs every 10 seconds for two minutes, leaving the remaining control crabs alone. The shocks lasted 200 milliseconds each.

Among the electrified crabs, 16 of 20 began walking after being shocked, a potential sign of avoidance behavior. However, 14 control crabs also began walking partway through the experiment. The remaining four crabs that received the shocks also tried to climb out of their tanks or displayed an aggressive posture.

Digging deeper, the researchers measured the lactic acid response in the walking crabs from both groups. They found that the crabs that had been shocked had nearly triple the levels of lactate in their bodies compared to the unshocked crabs, even when controlling for the greater physical activity.

“The data are thus consistent with the idea that shock induces a stressful pain-like state,” Elwood and Adams wrote in their paper. “Importantly, this fulfils a key criterion expected of animals that experience pain.”

July 2019

On Target

Researchers strive to make individualized medicine a reality

Marketplace

Sponsored Product Updates

IDT and Washington University join forces to increase access to the latest NGS technologies
IDT and Washington University join forces to increase access to the latest NGS technologies
As part of its commitment to advocate for the genomics age, Integrated DNA Technologies (IDT) aims to lower the barriers to access the latest NGS technologies.
Bio-Rad Launches Bio-Plex Pro Human Immunotherapy Panel 20-plex Multiplex Assay, a targeted tool for researching signaling networks in Immunotherapy Research
Bio-Rad Launches Bio-Plex Pro Human Immunotherapy Panel 20-plex Multiplex Assay, a targeted tool for researching signaling networks in Immunotherapy Research
Bio-Rad Laboratories, Inc. (NYSE: BIO and BIOb) July 15, 2019 announced the launch of its Bio-Plex Pro Human Immunotherapy Panel 20-plex, a multiplex immunoassay that offers a targeted approach for Immunotherapy Research.
DeNovoMAX - NRGene's new genomics tool to meet a major agbio need:
DeNovoMAX - NRGene's new genomics tool to meet a major agbio need:
NRGene has launched a new product that aims to empower breeding and maximize agricultural yield as part of the Denovo assembly product suite offered by the company.
Overcoming the Efficiency Challenge in Clinical NGS
Overcoming the Efficiency Challenge in Clinical NGS
Download this white paper to see how an ECS lab serving a network of more than 10,000 healthcare providers integrated QIAGEN Clinical Insight (QCI) Interpret to significantly reduce manual variant curation efforts and increase workflow efficiency by 80%!