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View Full Version : urchin digestion?


Rae C.
11/18/2008, 10:44 PM
Okay, so we paused by the tank before going to bed and saw the urchin on a rock where we could really look at it. Then the kids started laughing hysterically. The orange spot in the middle (I'm thinking it's an anal organ, but the kids thought it was an eye) was pulsing in and out of the body of the urchin. VERY bizzare! When I told them I thought that was the anal organ, they were totally grossed out. They were joking about constipation, and doing sound effects for it!

Is that normal behavior for an urchin? My son wants to know if he might have swallowed a bristle worm...

lockekeyy
11/18/2008, 10:50 PM
If you're looking at the bottom of the urchin... you're actually looking at its mouth. It's anus would be on top. Hope that might help clear up what you're seeing. If you were looking at its mouth, then yes, you should expect pulsing to occur when trying to feed. As for the anus side... not too sure.

will16
11/18/2008, 11:32 PM
Yes mine does that as well. It seems it does it while it's eating and I think it is 'passing' something.

crvz
11/19/2008, 08:01 AM
I would expect it to be rather normal behavior, and I'd surely side with the urchin in a fight between it and a bristleworm. Nothing to worry about in my opinion.