Deep sea shrimp glow, but it doesn’t produce a love connection

Light organs of deep sea shrimp
Light organs of deep sea shrimp

Deep sea shrimp glow, but strangely enough, that’s not part of their sex appeal.

Lorian Schweikert thought that glowing patterns of bioluminescence might be just what shrimp are looking for in a mate, but as it turns out, their eyesight simply isn’t good enough to differentiate glowing patterns.

Schweikert conducted the research as part of FIU’s Crustacean Genomics and Systems Lab with Heather Bracken-Grissom, assistant director of the Coastlines and Ocean Division in the Institute of Environment. The team studies bioluminescence in deep-sea animals. During a research trip at sea, Schweikert noticed the incredible diversity of size and shape of light organs in deep sea shrimps.

“From there I set out to determine if they use these patterns to identify one another while down in the darkness,” Schweikert said.

She tested three different species of deep-sea shrimp that each have different types of light-producing organs. Her team then used zooplankton nets to capture the shrimp from depths between around 500 and 5,000 feet. They measured the eye diameter and body length of each one they captured. With a little mathematical modeling, they predicted how far the shrimp can see. With a microscope and special camera, they were also able to learn a few things about the resolution of the shrimp’s vision.

The research team determined the eyesight of the shrimps used in the study weren’t strong enough for them to recognize one another using the pattern of their bioluminescent light organs. 

This study leads one to believe that these deep-sea shrimps do not seem to use their eyes to recognize other members of the same species by their bioluminescent light patterns. This leads to even bigger questions about how these shrimps use their vision and light organs to thrive in the harsh environment of the deep sea.

Answering these questions is important to Schweikert who points out that more people have set foot on the moon than have ventured to the deepest parts of the ocean. She hopes the more scientists can learn about the ocean, the more people can do to protect it. This is especially true for bioluminescent animals where human disturbances can obscure bioluminescent signals these animals use to communicate.

And she hasn’t closed the book on shrimps finding a date through bioluminescence. Many questions remain about the intensity of bioluminescent light produced by the shrimps and about the distance in which they can see each other at depth, so she is leaving open a willingness to return to this question as scientists learn more.

Schweikert continues her studies on bioluminescence in shrimp at the University of North Carolina Wilmington as an assistant professor in the Department of Biology and Marine Biology.

To learn more about Schweikert’s study published in Ecology and Evolution, click here.

Valerie Ramirez contributed to this article.