I have spent my first two weeks at OIMB planning and preparing for my project. For which, I will be creating an updated identification guide to Nemerteans (also known as ribbon worms) found locally around Coos Bay. As of now, existing identification guides for ribbon worms are vastly inadequate for a multitude of reasons. Firstly, many Nemertean species are undescribed, some of which are cryptic and look like other species. Secondly, many species are called by the wrong name, being mislabeled as another species that inhabits a completely different geographical area. For example, a local worm was inappropriately given the same name as a European Nemertean that it looked similar to, despite being a completely distinct species. Additionally, one species may be listed under multiple names due to intraspecific variation, in which individuals of the same species may look vastly different from each other. Thirdly and finally, while existing guides provide photographs of worms, they are not in color. As Nemerteans often have striking colors or very few features, it is important to show the color and shape of them to make identification easier and more accurate. Therefore, my identification guide will be a picture guide to the most common and most conspicuous species of intertidal ribbon worms in Southern Oregon that corrects the names of inappropriately named species and alerts users to the presence of multiple cryptic species (ones that look very similar to each other) when they occur.
Specifically, I will focus on the class Hoplonemertea, or ribbon worms that have a stylet, a dagger-like structure that Nemerteans use to stab prey with while hunting. I chose to work on this group since they have such a unique mode of predation and it will be a challenge to examine these stylets under a microscope. To begin the process of creating the identification guide, we capitalized on the exceptionally low tides this week to collect worms in the intertidal zone. The worms were exceptionally difficult to spot at first (being only a few millimeters or centimeters wide), but I found a few by the end of the field trip. This was my first “professional” tide pooling expedition and was very informative for me in regards to both Nemerteans and other marine invertebrates. On the molecular side of the project, I learned how to extract DNA from worms, amplify it, and purify it. For this project we will be looking at the cytochrome c oxidase subunit one gene, or the COI gene. We use this gene because it mutates quickly, so that each species has a unique code in this section of their DNA. Once we obtain the isolated genetic sequence, we will send it to a lab for sequencing. Upon receiving the sequence, we will clean it up and run it through a database. When comparing our gene to other COI genes in the database, we want to determine whether the species has already been described or not, if the species name is not meaningful (the worm has been grouped with species not related to it), and if there is a cryptic species complex (a group of worms that look alike but represent distinct, often closely related species). Once we have this updated information about locally found ribbon worms, we will begin writing the identification guide. It took me an entire week to learn the molecular techniques that I will be using this summer, as I have never worked with DNA in this capacity before, but I am happy to be learning such a scientifically universal skill and I already feel way more comfortable in the lab than when I started. I am still working on identifying the worms using morphological features (ones we can see with a microscope) prior to our genetic analysis of them and there is a recurring theme of Nemerteans looking extremely, almost ridiculously, similar to each other. It will be a challenge to differentiate between “cream-colored featureless worms,” but I am excited to continue learning about such an understudied group of marine invertebrates. In the coming days, we will begin processing our worms by prepping them for DNA analysis and photographing them for the identification guide. Updates on that will be coming soon.
0 Comments
Leave a Reply. |
AuthorI am Jacob and am from Rancho Cucamonga, CA. I am a rising Junior at Pomona College in Claremont, CA who has never studied marine biology in school before but has always been interested in it. I am incredibly excited to spend the next two months working in Svetlana Maslakova’s lab studying Nemertean (ribbon worm) biodiversity through genetic analysis. Archives
August 2021
Categories |
Proudly powered by Weebly