Part 4 of our “Smorgasbord of Food Offerings from the Sea” series
by Janice Edwards
To conclude our series on Smorgasbord of Food Offerings from the Sea, we thought we would offer up some nice flowers to gaze at while you eat your grilled sea pork, sauteed sea apples, and some warm sea biscuits. Therefore, this post is on the organism known as the sea pansy, Renilla reniformis.
Sea pansies are fleshy and have a petal shape reminiscent of a...pansy. They are a type of soft coral classified in the order Pennatulacea, and are actually colonies of small polyps working together cooperatively to benefit the organism as a whole. The petal-shaped body, which can be up to 2 inches in diameter, is connected to a stalk known as a peduncle. It is this primary polyp, the peduncle, that anchors the sea pansies to the the ocean floor by thrusting itself into the sand or mud.
Living and Working Together Cooperatively Fact #2: On the upper side of the pansy are two types of secondary polyps. One type is a feeding polyp which secretes gooey mucus to trap zooplankton and organic matter floating nearby. From there the food is sent to a common digestive system for the whole colony to partake. The other type of secondary polyp can be found between the feeding polyps. They are like little water pumps and are responsible for inflating or deflating the entire colony. Very handy if the organism is trapped on a sandbar during low tide and needs to hide from predators!
Living and Working Together Cooperatively Fact #3: Sea pansies have an interesting way to ward off predators that also involves cooperative action. At night, if a predator approaches or touches it, the colony distracts it by sending out pulsating waves of bioluminescent greenish light. Can you say--shades of Jedi lightsabers? A green fluorescent protein along with an enzyme creates this light show. The enzyme is known as luciferase from the Latin word Lucifer meaning light bearer.