This week, I had the exhilarating experience of being in the company with a most illustrious member of the invertebrate phylum of Chordate. The fascinating personage I had the pleasure of meeting was a colourful and unusual animal known commonly as the sea squirt. The name of this particular interviewee is Poly, and she was gracious enough to answer a few questions for this article. She presented to me a clear view of some of the wondrous characteristics of a sea squirt, as well as presenting her rather high opinion of herself. But it is at the beginning of the conversation that I must start, and so I shall.
It was rather difficult to carry on an interview beneath the waves, especially with a creature fastened to the rocky bottom, but I managed it. I was, however, forced to speak through a diving mask which made it difficult for Poly to understand my words. Ignoring the many times she asked to have my questions repeated, and the many times I myself requested for her to do the same with her answers, this is roughly our discussion beneath the ocean.
To begin with, I asked (very politely) if she found it wearisome to be anchored immovably to the ocean bed while so many other aquatic beasts were free to swim where they liked.
“Oh, not at all!” was Poly’s cheerful reply, “ It is quite pleasant down here among the sand and stone. We sea squirts had our chance to roam when we were young. Back then, you could have easily mistaken one of us for a tadpole for we had, in our early days, a distinct tail and head. It was then that we were free.”
“Your larvae look like tadpoles?” said I, “So then you once had a mouth, and eyes like true tadpoles?”
“No, I did not have a mouth. None of our children eat. Instead our larvae live off of food reserves from their eggs. But they do have primitive eyes.”
“Sooo,” I queried, curious to discover more, “how are you able to eat now as an adult? I don’t see any teeth or mouth.”
She answered, “But you do see a mouth.”
“Do I?” I said, completely perplexed.
“Yes. The opening at my top is my mouth. I eat great big mouthfuls of salty water and it passes through a net-like organ in my throat. This catches any tiny morsel of delicious food that might be in the water and that is how I get my meal. It is much easier than how you people eat.” She concluded accusingly.
“We manage.” I replied while mentally preparing the next stage of my interview. But Poly did not give me or my questions a moments chance.
“We too manage!” She burst forth, “ In fact, we manage very well without a tongue, or teeth, or feet, or head, or valves to our hearts, or a nose, or nails, or bones or-or..” At this point she ran out of breath, and words while I looked on, rather surprised at this unexpected turn of events. Then, sly as a fox, I offered her the words: “Or hair?”
“Or hair!” she victoriously concluded. With that I swam away, rising steadily to the surface, an amused smile playing hide-and-seek upon my face. What a day!
Sea Squirts are bag-like animals in their adult stage, but tadpole-like in their larval stage. They are at this stage much smaller than tadpoles,though. But when they are grown, they sink to the bottom of the vast ocean and there attach themselves by means of root-like fastenings. These immensely colourful creatures have two openings, one at the top which is lined by eyespots which are sensitive to light and touch, and one on their side.