Marine Ostracods

 Bioluminescent and non-bioluminescent ostracods we study can be are found in the Caribbean sea in the reefs and grass beds off of Belize. They are in the Photo taken by Jim Morin http://www.eeb.cornell.edu/morin/ResInt.htmlphylum Arthropoda; therefore, They have an exoskeleton that is composed of chitin. This exoskeleton is in the form of a bivalve that completely encloses the body. As you can see in the picture to the left, ostracods have a compound eye that is used to track light. Although this eye is similar to that of insect it evolved from a different genetic branch and is an example of convergent evolution. In the picture to the left, you can also clearly see what makes these ostracods really "stand out." That is the yellow rectangle below the eye. This is their lightbox where they mix proteins and enzymes to produce their amazing mucus. This mucus is the bioluminescent part of the organism that is spit out leaving a floating ball of glowing mucus that can last a few seconds.

The mating displays of bioluminescent ostracods are unlike any species in the world. In the short time after the sun sets and the moon rises, there is a short period of darkness. It is in this darkness that thousands upon thousands of ostracods start their displays. In the beginning, a species of ostracods begins to swim upward leaving a string of lights bobbing in the tide to mark it way. A different species will group together and create a fan like display the goes parallel to the sea floor. Yet another species will begin its decent, together all these species create an awe-inspiring, short lived spectacle. Despite these amazing displays ostracods were not officially described until the 1980's. Since then there has been much information collected, but as always as we uncover more information we realize that we are truly just scratching the surface of these magnificent creatures.

Our lab had noticed an interesting trend of these ostracods. In grass bed type communities of ostracods, we find 1-3 different species. However, when we look at the reef we find 8-12 different type of species. We are using GIS cost analysis program along with molecular techniques to study if an increase in the cost of movement can cause a species to diverge.

For a more detailed description of the ostracods we will be studying check out this page made by a student ostracods.