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Wherever I Wind Up
Author: R.A. Dickey
Category Archives: Science
Sea urchins feed on kelp using a set of 5 teeth called the Aristotle’s lantern. As they eat their food, they leave these little star shaped chew marks. This piece of bull kelp (Nereocystis) was fed to several green sea urchins at Friday Harbor Labs.
A video of specialized “stinging” cells called nematocysts. In a fraction of a second, these cells discharge a thin shaft-like structure that may bear spikes on it. In the video, one can actually see the discharge of individual nematocysts. Used by jellyfish to capture prey or ward of predators, the combined effect of thousands of nemtocysts discharging can be significant indeed.
Pod of killer whales off San Juan Island. July 2011.
Recent genetic analysis of the resident orcas of Puget Sound has revealed evidence of inbreeding. The results are in contrast to the belief that the orcas rarely, if ever bred within their own pod. However, much of the pattern was driven by the oldest male “Ruffles” who apparently passed away last year.