It is not often one can go out into the field and discover a possible new species; however last semester on a field trip to the Hawai‘i Kai reef flats I may have just done that. As the class and I were wading in the water looking for invertebrate animals to collect, I came across and interesting pink substance on some algae. At first glance I thought it was some sort of a pollutant in the water like silicon and I ignored it initially; however as I continued out further I continued to see this pink substance and upon further observation I realized it could be a sponge or a tunicate. I decided to collect a sample to bring back to shore to identify.
Back at shore my class mates and I used a book to identify the organisms we had collected; however to my surprise the pink sponge like organism was not in the book. This really got my attention and I decided that I needed to bring a sample back to the lab for further study. The days following the field trip I spent google searching and asking around the biology department about my sponge, no one seemed to be able to help. The question then became what to do to identify this organism, so I went to my genetics professor and told him the story about the sponge and asked if I could use his lab to extract a DNA sample. He agreed to allow me to use his lab and in no time I had a DNA sequence and I thought that would finally reveal the true identity of my sponge.
Well I didn’t quite get an exact hit but was able to at least narrow the sponge down to the family level of taxonomy. Early data results suggest that my sponge sample is in the family Darwinellidae, commonly referred to as the “horny” sponges. I am currently working on extracting different portions of DNA from the sponge to compare to other known species. With more DNA data I can use a mathematical model to infer the phylogenetic evolution of this species and determine whether or not this sponge is a new species; however even this data can only be considered as a phylogenetic hypothesis. So the science journey continues.
-by Michael Wallstrom
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