How Do Snails Get Their Shells? Interesting Facts For Curious Kids

Joan Agie
Nov 02, 2023 By Joan Agie
Originally Published on Jan 05, 2022
White tipped snail on fresh leaf.

Snails come in a variety of colors, sizes, and shells.

A snail's shell is more than just a body component, from the medium-sized garden snail with a pale beige shell to the racy red, yellow, and black stripes on the exceedingly uncommon red racer nerite snail. Snails will not come out of their shell even if any animal pokes them.

The snail's shell is there from the beginning of its growth, is linked to the snail, and develops in a spiral shape with the snail. Snails can be killed by sprinkling salt on them.

The snail's body comes into touch with the soft-shell material, the innermost layer, which is made of mother-of-pearl or shell nacre, a thick horizontally packed type of conchiolin that is placed atop the periostracum as the snail is fully grown.

Snails have a real coelom, a body split into three parts: head, visceral mass, and muscular foot, with organ systems for circulation, breathing, digestion, excretion, nerve conduction, and reproduction, as do all mollusks.

Snails prefer the top leaf litter of woods, grass of ancient fields, and wetlands, but they may also be found in more disturbed habitats like fruit trees, busy gardens and fields, riversides, suburbs, and even the city environment. Snails and slugs with no visible shell are called 'land snails.'

Are snails born with shells?

Snails, oysters, clams, and mussels utilize an organ called a mantle to release calcium carbonate layers that crystallize and solidify, and thus snail's shell forms.

Despite the fact that the shell is translucent and delicate by nature. Snails need calcium to harden their shells, and a newly hatched snail gets calcium by devouring its very own egg covering. Snails are born with a basic shell after hatching from eggs.

The embryonic shell ,also called the protoconch, has a distinct sculptural design from the rest of such shell. When a snail is hatched, it has this section of its shell.

This part of the shell expands as the snail does. The quantity of whorls grows as it expands.

A reflected or thickened lip appears on the adult snail's shell of certain types, such as camaenids and pupinids, then no further growth occurs. Adult growth is typically reached at four and a half to five and a half whorls. Regular slugs have more whorls compared to semi-slugs.

Other snails, such as charopids (pinwheel snails) and helicarionids (glass snails), exhibit nondeterminate development, and the snail continues to add to the shell after reaching adulthood, a process known as gerontic growth. Snails require a diet rich in protein, conchiolin, and calcium in order to develop a hard shell.

A snail has the ability to cure itself. It can mend minor damage to its shell, but it cannot regrow it from scratch.

A snail's shell is essential to its survival, much as the bones of humans are. The snail's shell is used to protect and give structure, and if predators tried to take a living snail out of it, they'd only be able to get a portion of it out since they're stuck to the shell.

How are snail shells developed?

All snails are born from eggs. Although certain species are ovoviviparous, meaning that their eggs hatch inside the mother's body, the parents usually deposit them on loose soil or attach them to rocks. After that, the infants wriggle out and confront the world. Snails prefer soil that is well-limed.

A snail's shell begins to develop during the gestation phase. Mollusks, such as snails, have a vital organ called the mantle.

Making and developing shells is a process that takes a long time. Snail shells are mostly composed of calcium carbonate (though small amounts of protein also go into the mix). In order for the organism to produce these shells, the mantle generates an electric current that aids in pushing calcium ions into position.

The eggs hatch after a few weeks, and tiny baby snails emerge with their shells intact! The baby snails' shells are colorless, fragile, and delicate at this stage.

The baby snail consumes the egg from which it hatched because calcium in the egg aids in the hardening of its shell.

Baby cornu aspersum is the name given to a baby snail of the garden snail kind. The body of a garden snail is brownish soft and coated with sticky mucus, and its shells are yellow or cream-colored with brown spiral patterns.

A protoconch, the initial component of a snail's shell, develops before it hatches. Healthy food becomes a priority as our tiny snail emerges from the egg. A tiny opening, or "mouth," is included with the protoconch. From below, the mantle deposits a new layer of calcium carbonate and proteins in the mouth.

The shell develops as the fresh material solidifies at the mouth. The spiral coils emerge around the protoconch, which slowly spins around and around, eventually reaching the apex — or highest point — of the snail's growing shell. The protoconch will either stay in place permanently or break off at some time, depending on the species.

To strengthen and grow the shell, they will need more calcium. Newborn snails are driven by instinct to eat whatever remains of the calcium-rich egg from which they have just exited. As a result, a lifetime habit is born.

Snails of all shapes and sizes must continue to eat calcium-rich diets. This is one of the reasons why mollusc is generally seen as a pest; a few of them enjoy eating spinach, broccoli, turnips, and other calcium-rich vegetables. They can also obtain their calcium fix by chewing on limestone or ingesting dirt.

Focused portrait of Snail on leaf.

What are snail shells made of?

Snails as well as any other mollusc use a method called biomineralization to manufacture their shells. They exude an organic matrix of proteins, lipids, and carbohydrates which provides a basis for such hard mineral components of the shell through a shell gland.

Calcium carbonate is the snail shell material that makes up the shells of mollusks and seashells. Calcite and aragonite are two different types of it.

Snails are gastropods that belong to the Mollusca Phylum. The gastropod mollusks is a secretion secreted by snails.

Many molluscans have shells, and there are almost 100,000 live molluscan species. Oysters, the nautilus, clams, and the 'living fossil' chiton are some additional well-known shelled molluscans. Slugs (essentially a larger, shell-less form of the snail), octopuses, and squids are examples of non-shelled mollusks.

Molluscan shells are made up of a complex lattice of minerals and organic compounds. Mammalian bones are made up of a calcium-mineral matrix as well as the protein collagen. Mollusk shells, on the other hand, differ from the bone in terms of the minerals they contain and the number of minerals in their shell.

The mineral composition of shells can range from 95- 99% by weight. Organic matter makes up the remaining 1-5%. This effectively transforms the shells into biologically formed rocks!

Do all snails have shells?

Some snails, known as gastropods, do not have shells. They wanted to squeeze into locations where a snail shell couldn't. Slugs can creep into places where a snail with the same body size (but no shell) would never be able to.

Snails and some types of slugs, on the other hand, spend most of their lives in water. The fact that snails have shells is the most visible distinction between them and slugs. The shell of a snail is similar to a house in that it transports itself on its back. While slugs do not have a protective shell.

Slugs are snails without shells. However, land snails aren't the only ones who lose their outer shells. Colorful nudibranchs may be found in the water, and they can live without a shell. The term 'snail' is a generic term for shelled gastropods.

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Written by Joan Agie

Bachelor of Science specializing in Human Anatomy

Joan Agie picture

Joan AgieBachelor of Science specializing in Human Anatomy

With 3+ years of research and content writing experience across several niches, especially on education, technology, and business topics. Joan holds a Bachelor’s degree in Human Anatomy from the Federal University of Technology, Akure, Nigeria, and has worked as a researcher and writer for organizations across Nigeria, the US, the UK, and Germany. Joan enjoys meditation, watching movies, and learning new languages in her free time.

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