Week 2: Keep Your Friends Close but Keep Your Anemones Closer: On Meeting the OIMB Community, Tide Pooling, and Fertilizing Marine Invertebrates
The OIMB community is filled with an enthusiasm for animal biology unlike I’ve ever experienced before. Here, conversations from lab spill over into lunch and I am endlessly amazed by the depth of knowledge I encounter in my peers. During our conversations, I often wish I could live a thousand lives each devoted to the intense study of a different organism; I want to study deep sea larval activity and barnacle parasitism and chiton larval morphology, and I feel incredibly fortunate to be surrounded by amazing researchers whom I can live through vicariously. This is the contagious, effervescent energy of OIMB, where professors and graduate students alike welcome you into their labs to observe larval cultures, crab tanks, and collections of comb jellies dancing in their jars.
While there is much to learn at the lunch table, there is even more to learn by surveying the local ecosystems. My first morning of tide pooling, I felt as if I were exploring an alien planet. We arrived at the beach in the early morning, when the tide was very low, to a vast landscape of algae and kelp-covered rocks which jutted at all angles to form an array of tide pools. As I clambered about, I stepped on something squishy that I assumed to be a rock—and met my first gumboot chiton (see picture top left). Nicknamed the “wandering meatloaf” for its reddish-brown hue and fleshy body, Cryptochiton stelleri are common to local tidepools (and easy to mistake for rocks!).
The contents of the tidepools themselves were equally bizarre and enthralling. While anemones, sea urchins, and sea stars resided in many tidepools, no two tidepools were exactly alike. Fish darted about in some, while colorfully-spotted nudibranchs undulated across the bottom of others. I think that the most exciting find of the day, however, was this small octopus!
Although I encounter fewer octopuses in the lab, I find my work inside just as enthralling as tide pooling. My training for Svetlana’s lab has focused primarily on practicing lab techniques for extracting DNA, amplifying specific genes, utilizing gel electrophoresis to verify the successful amplification of the specified genes, then purifying and quantifying the isolated genes before sending them off for gene sequencing. These lab techniques will enable us to utilize DNA barcoding to determine new or cryptic (morphologically indistinguishable but distinctly different) ribbon worm species. Much of Svetlana’s work centers around the nuances of determining what a biological species is, and I am excited to delve more into this complex subject.
My training for George’s lab has focused primarily on sea star (Patiria miniata) and sea urchin (Strongylocentrotus purpuratus) fertilization, oocyte injection, and familiarizing myself with compound and dissecting microscopes. This week my fellow lab interns and I learned how to extract sperm and eggs from both sea stars and sea urchins, and had the opportunity to watch the fertilizations occur live under a compound microscope. To extract sea star gonads, we utilized a biopsy punch to make a circular incision on the side of a sea star arm and then removed the gonads from the body cavity using a pair of tweezers. To extract the sea urchin gonads, we vigorously shook the urchin for several minutes until the distressed specimen expelled a cloud of eggs/sperm from its gonopores into a beaker of seawater (see pictures below).
We’ve been watching our fertilized oocytes develop into larvae, and have even observed the blastula formation of developing sea stars using a time lapse video (check out the link below). I promise to post more pictures of the larvae as they develop.
My brain is overflowing with new information, and I hope yours is too. Next week I’ll delve more into describing my research projects—until then, take care, and comment below if you have questions!
“Instructions for living a life./ Pay attention./ Be astonished./ Tell about it.” (Mary Oliver)