Annette Govin­darajan is fas­ci­nated with studying jel­ly­fish, specif­i­cally their com­plex life cycles. That pas­sion was forged years ago after working with hydro­zoans, a jelly of the stinging variety.

I was intrigued by how they could occupy dif­ferent parts of the marine envi­ron­ment,” said Govin­darajan, a lec­turer in North­eastern University’s Depart­ment of Earth and Envi­ron­mental Sci­ences, refer­ring to their polyp, jelly and larval life cycle stages.

Govin­darajan is pri­marily inter­ested in researching the genetic and evo­lu­tionary dif­fer­ences between jel­ly­fish as well as other gelati­nous ani­mals, and she recently coau­thored a paper fea­tured on the cover of the Journal of Plankton Research that explores these evo­lu­tionary rela­tion­ships in thali­aceans —gelati­nous, plank­tonic inver­te­brates that drift along in the ocean. She is also working on a project to bar­code species of jel­ly­fish with col­leagues at the Uni­ver­sity of Con­necticut and the Woods Hole Oceano­graphic Insti­tu­tion, where she is a research associate.

The first step in bar­coding involves extracting a jellyfish’s DNA, and using a tech­nique to amplify copies of the target gene. Govin­darajan said these copies make it pos­sible to sequence the DNA and deter­mine which are unique to a par­tic­ular species. These “genetic fin­ger­prints” ulti­mately help to improve species iden­ti­fi­ca­tion, she said, and build upon existing DNA bar­code data­bases that sci­en­tists can uti­lize in their research.

This work aligns with a larger push among researchers to increase efforts to bar­code a wide spec­trum of living beings, which can com­ple­ment clas­si­fi­ca­tion and advance other areas of sci­ence such as ecology. “In many groups of ani­mals, there often aren’t a lot of spe­cial­ists capable of iden­ti­fying them down to the species level. Having a genetic tool to do this fairly easily would really help,” Govin­darajan said.

How­ever, she said researching gelati­nous ani­mals can be tricky given the chal­lenges asso­ci­ated with col­lecting them since they are a del­i­cate struc­ture and can break apart at the softest touch. “They can be hard to work with,” she said. “The sam­ples we’ve used are col­lected by divers by hand.”

Govin­darajan is also inter­ested in how large blooms of jel­ly­fish form in the ocean. She said reports of these blooms are increasing in dif­ferent parts of the world, and they often happen in pol­luted waters where algae have died and decom­posed. While many ani­mals can’t sur­vive in these low-​​oxygen zones, jel­ly­fish are found to have a tol­er­ance to those waters.