Alan Fox
Posts: 1556
Joined: Aug. 2005
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| Quote (Henry J @ Aug. 16 2007,10:32) | If anybody wants a guess from an amateur, I'd guess that slugs rely more on shelter (i.e., being under things), whereas snails carry a partial shelter around with them. But that's at a cost; building that shell, and putting out the energy needed to carry it while moving around - slugs aren't paying that cost; their way works for them (yucky as it is), else they'd be extinct by now.
Just my two cents.
Henry |
Me, miss! Me, miss!
Where I live, during hot, dry conditions, in daytime, you find many snails with opercula tightly closed in vegetation such as vines about 1 metre from the ground. The strategy seems to help avoid dessication, as the ground surface can become much hotter than the air above. The shell is an essential element in this strategy, and may enable snails to thrive in drier climates. I have not seen a slug here, and our lettuces do very well.
PS among all the other questions that I am sure you will be soon getting around to answer, when you have time, please don't forget:
VMartin:
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I am not sure of that but the fact of DNA preserved after 70. milion years is very weird, isn't it? |
I suspect that DNA allegedly from dinosaur bones was actually a contaminant. But don't take my word for it.
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I suspect that DNA allegedly from dinosaur bones was actually a contaminant. |
-John A. Davison. link
PPS
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