Outreach | OSU Winter Wonderings: Under Sea Learning - Otoliths and Nematocysts

Winter Wonderings is a program put on by Oregon State University's PreCollege Programs. The program is geared towards gifted, highly talented 3rd, 4th, 5th, and 6th graders. Will Fennie and I taught a course examining the importance of knowing fishery age structures and how sea anemones acquire nutrition. For the fisheries portion of the course, we introduced students to otoliths (essentially fish ear bones). Otoliths are similar to tree rings in that we can count the age of the fish (by counting rings laid down annually) and we can determine how large the fish was and what the environment was like that it lived in from year to year. For the sea anemone nutrition part of the course, we introduced the students to the concepts of heterotrophy and photoautotrophy. All sea anemones have structures called nematocysts; stinging cells; that are located on the sea anemone's tentacles and are used to deliver toxins into and capture prey that swims by -  this is the heterotrophy part. Some sea anemones house microalgal symbionts which undergo photosynthesis and provide some sugars to the sea anemone -- this is the photoautotrophy part. The students observed microalgal symbionts in sea anemone tentacles and then induced the nematocysts to fire using a chemical stimuli (vinegar). Check out the video to see nematocysts firing!