It's looking up?
Wow Aydin, what a great picture, and what a striking design it makes; it would make a fine logo! I have never ever seen a snail or slug hold its ommatophores perfectly straight up like that, in fact I didn't think they could even do that; this one has great muscle control! I know they don't have great vision, but am tempted to say that the snail is looking straight up, but actually in this position the eyespots are facing backwards slightly, so it is tempting to say that it is perhaps trying to look somewhat behind it and over the shell, towards the main light source, a window or overhead light? I know they don't see well, but they do seem to look in one direction sometimes. Take a look at this image:http://en.wikipedia.org/wiki/File:Tigerschnegel_Einablage.jpgWhere you will see that it seems as if the Limax maximus is looking upwards, I think because the board under which it was nesting was suddenly removed and the light was a surprise to the creature. Nonetheless, you can see that the tentacles are curved upward, as is usually the case, not straight up to attention like your cute little juvenile here.Best,Susan J. Hewitt
I don't think it was looking at anything. As you note, Susan, terrestrial gastropods can't really see. I have done some simple tests with several species of snails & slugs & determined that their tentacles don't react (i.e., withdraw) unless an object is brought very very close, within ~1 mm, of the tip of the tentacle. Therefore, I believe the vertical holding of the tentacles in the picture signify something other than a visual response.
Your juvenile reminds me of Gary the Snail. : ) http://spongebob.wikia.com/wiki/Gary_the_SnailDoes it always hold its tentacles vertically? I once saw a snail whose tentacles were essentially fused together, which I guessed to be a strange congenital defect. Maybe this guy has some unusual musculature.
I see Megan got to it before me, but I was thinking that it looked like a cartoon snail.
You mean Spongebob's snail Gary? Meow...No, my snail--maybe I should name him/her--can move its tentacles around.
Yeah, it's true that snails and slugs can't look "at" something like mammals can, because the eye spots are just simple light sensors, not real eyes, no lens and so on. But I assume they can perceive the difference between a really dark area and a really bright light. Do they move away from a bright light source preferentially? Have you tried that experiment? I imagine LED light is good for brightness without much heat.Anyway, does this little creature hold its tentacles like that almost all the time? Or only sometimes? It's really comical, I have never seen a snail do that.Susan
Very pretty snail.
maybe it's just happy to see you?
I've read that snail eyes do indeed have lenses, which means they can focus their vision to some extent.I don't think they can see very well, but I suspect they can see better than we think they can.
This is what I imagine was happening just off-camera.
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