Wednesday, May 19, 2010

How do snails get bigger, when they start with tiny shells? Do they shed them? Where do they get a new one?

A snail enlarges its shell as it grows, using a specialized organ called the mantle, which concentrates calcium salts from the snail's diet, and deposits them along the lip of the shell (the thin edge around the shell opening). A snail does not form chambers in its shell as Nautilus and ammonites do. Those animals are not snails. The inside of a snail shell is one continuous spiralled chamber, from the aperture (opening) of the shell all the way back to the apex (the pointed end). Many snail shells show growth lines on their outer surface, parallel to the lip, indicating periods when new shell material was being deposited.

How do snails get bigger, when they start with tiny shells? Do they shed them? Where do they get a new one?
The shell is a living part of the snail just like a turtle and grows as the snail grows.
Reply:As the snail grows, so does its calcium bicarbonate shell. A snail will close off a section of its shell and add a new chamber as it grows, each chamber being larger than the previous one by a constant factor. As a result, the shells forms a logarithmic spiral; most are right-handed, meaning that the whorl is on the right hand side of the shell. At some point, the snail builds a lip around the opening of the shell, stops growing, and begins reproducing.
Reply:Snails grow in their shells. When the shell is too small for them, they find a suitable "hiding place", where they then "abandon their old shell and grow a new one. Aquatic snails go through this cycle once a month while terrestrial snails go through this cycle 3 - 4 times a year. Usually during spring.
Reply:just wanted to say i loved the question, and although i never thought to ask i loved to know the answer.


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Reply:Shells grow outwards in a spiral fashion, starting from the smallest point (usually the pointy end of the shell) and working its way outwards. That is why snail shells typically have spiral shapes.
Reply:Shell is an exo-skeleton - it is not dead tissue - it grows with the snail
Reply:You can get them at Woolworths.
Reply:The shells keep adding extra segments on as they spiral around. It is the same shell. The empty ones that you find are snails that have met an untimely end through being eaten by birds. If you look at an ammonite (especially one that has been sliced in half) in the geological section of your nearest museum it will be easier for you to grasp the concept of how the shell is formed.
Reply:the shells grow on them
Reply:Yes, you've got it. The find a bigger, empty shell and grow into it.


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