My name is Marisa McDonald, and Marine Biology has been my passion from a young age. However, since I decided at age 7 that I would be a marine biologist (and told everyone who would listen about it) my interests have moved far away from my initial life goal of being a dolphin trainer. I graduated from the University of Miami in May with a degree in marine science and biology, and will be starting a PhD program with Dr. Megan Porter at the University of Hawai’i at Mānoa next month studying stomatopods, commonly known as mantis shrimp. However, before the exciting move to Hawai’i I have returned to Miami one more time for a research cruise with my new lab to look for deep sea crustaceans on the Walton Smith, a ship that docks at the University of Miami that I have been looking at for four years and now have the opportunity to explore.
My mission on the cruise is a bit different than the rest of the researchers. The main focus of the cruise is to look for deep-sea bioluminescent shrimp; however I am in the search of stomatopod larvae. Stomatopods, commonly known as mantis shrimp, have one of the most complex eyes in the animal kingdom. Adults have compound eyes with trinocular vision in each eye; to compare, both eyes working together in humans give us binocular vision. However, the complex mantis shrimp eyes only form upon the final molt to adult form. At the larval stage, they have a much more simple eye. When they begin the transition from larval stage to adult, the adult eye begins to form next to the initial eye. When the transition completes, the initial eye dissolves and leave the adult eye in its place. This means that an animal may have four eyes for a range of a few hours to several days!
The focus of my studies will be on this transition, and understanding how the eyes are developing from two eyes, to four, back to two. This trip is my first experience actually working with the animals. While I have seen adult mantis shrimp, and a few larval animals in the lab, I didn’t fully anticipate the challenge of finding them. Many specimens have come up in our trawls; however, they are fully clear except for two tiny black dots (the eyes) and are at most around a centimeter in length. All of the animals from the trawl are placed on sorting trays, and I have to find these clear animals among many other types of shrimp, fish, jellyfish, and whatever else the net brings up. However, despite the challenges I have been able to sort out well over 50 specimens, which are being preserved for genetic testing when I get back to Hawaii. This trip is the perfect start to my continuing studies, and I can’t wait to see where the research will take me next!