Where Do Seashells Come From? Interesting Mollusks Animal Facts

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If you've ever been curious to know 'where do seashells come from?' our fun facts will help you find out.

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Shells are the calcium carbonate tubes of creatures including marine annelid worms of the Serpulidae family, lobsters and crabs where the shells are called exuviae, and sea urchins where the shells are called tests.

Mollusks, for example, oysters, scallops, land snails, and clams not only use calcium carbonate to build their shells but also protein, both of which are secreted from the mantle. These shells are typically made of chitin or calcium carbonate.

Seashells also called shells or sea-shell, are the hard outer layer typically created by a sea animal for protection and these shells become a part of these animals' bodies. Beachcombers pick the empty seashells on the beach. After the animal in the shell dies, the body is either decomposed or eaten by another animal, so the shells are empty. Seashells are considered to be invertebrates' exoskeletons. Most shells that wash up to the edge of the beach are from marine mollusks, as they have calcium carbonate shells that are stronger than chitin. Shells of brachiopods, horseshoe crabs, and barnacles are also found on beaches. Human beings have used shells since the pre-historic period. Shells are not just homes to creatures like hermit crabs or young fish but are also used by many different kinds of animals for nutrients to build shells of their own, and as building material by birds for their nests.

The term for the study of the protective seashells of the sea mollusk is called conchology. The calcium carbonate secretions are formed in layers through the mantle of animals. The study of all mollusks with a seashell is called malacology and a person who studies mollusks is called a malacologist. The shells not only protect the animal's body against predators but are also present for the sea mollusks to dig down through sand faster and more easily. There are many different kinds of seashells with varying colors and shapes. Some other types of shells except the seashells already mentioned are crab shells, turtle shells, and land snail shells. The marine species' shells are better colored and are usually well structured, though not always. There are more Bivalve and gastropod species compared to freshwater and land creatures, and their shells are more robust and large. Other water invertebrates with shells are Brachiopods, Annelids, Echinoderms, and Arthropods. Other seashells are formed from hard corals (coral skeletons), soft corals, protists, plankton, and Chelonians (plastron and carapace).

If you enjoyed reading these facts that explain where do seashells come from? then make sure to read some more interesting facts that answer the questions does cashmere come from and where does caviar come from here at Kidadl.

Where do heart-shaped seashells come from?

Heart-shaped seashells actually come from the heart cockle (Corculum cardissa) species of the Cardiidae family occurring around the Indo-Pacific regions.

Heart-shaped seashells are also called heart cockle (Corculum cardissa) and are a species of bivalve mollusk of the Cardiidae family. These shells occur in the Indo-Pacific regions of the world. It is symbiotically related to dinoflagellates (zooxanthellae) that live inside tissues. These shells also act as protection to the bodies of a skeleton-less mollusk. The two valves of the heart-shaped seashells are often asymmetric and are not equal. Although, when viewed from the top, they form a rough heart shape giving this mollusk species the common name. It looks like a usual cockle from the side and sometimes shows sinuosity. Smaller-sized shells have a more elongated shape whereas the large shells are more round and the growth rings are clearly visible. The white-colored lower valve has few regions that are transparent. There is usually a transparent mosaic pattern on the upper part. As there are microscopic algae, the mantle (lower siphon) and gills are dark brown in color. There are purple, blue, and reddish granule pigments on the outer surface of the shell's mantle. These shells can be found on the sand surface along with broken shells and coral debris. You can find these shells lying horizontally in a hollow that these animals excavate, usually covered in muddy deposits and filamentous algae.

Corculum cardissa species are called filter feeders as they feed on particles in water by straining unwanted materials. They have two protruded siphons and at the ventral, the shell slightly gapes. They draw water through one, expelling through the other, which extracts detritus and plankton. These species are also hermaphroditic, and once the eggs are laid, the larvae develop rapidly. After fertilization, larvae undergo metamorphosis a day later and they then settle on the bottom of the sea bed as juveniles.

Types of mollusk species include mussels, oysters, pipis, clams, and scallops.

Where do most seashells come from?

Most seashells come from oceans and include bivalves, cephalopods, gastropods, and Polyplacophora.

There are larger, more colorful, marine, shallow water mollusks in the warm sub-tropical and tropical regions in the world than in the temperate zones near the cold poles. The seashells are made of calcium carbonate. When the mollusks hatch out of the eggs they form the seashell in layers. The chemicals and salt material (like calcium carbonate) from the sea are also used. They also use protein from their own bodies. The main component of their body is the mantle that is used to build the outer shell. Protein makes the shell strong and light, after which carbonate and calcium are filled. A few of the chemicals are the same as are used in humans for making bones. These animals need to extend the shell to accommodate their growing bodies and add more layers of chemicals, salt, protein, and calcium.

Almost all species of hermit crabs can use the empty shells as protection after the mollusk dies and the body decomposes. The broken shells are not waste; a mollusk is able to produce layer upon layer of the needed materials for the colorful outer shell. Only after these creatures are dead and the body is decomposed, are the shells washed up to the edge of the shore. The variety of shells is due to different diets in different places around the world's oceans. These creatures find a variety of food in warm regions and as a result, different pigments produce different forms of shells. However, mollusks of cold ocean water eat only restricted food resources and produce dark shells. There are also microorganisms living in the aquatic environment of different oceans. The age of seashells, even though inaccurate, can be counted from the ridges on the shells. As they are quite important for the environment, it is suggested not to take them away from the beach.

Where do seashells come from in lakes?

Seashells from lakes come from freshwater, pearly unionid mussel, apple snails, and land snails.

Seashells found near lakes are called non-marine seashells. So, the seashell term is loosely applied to these creatures that do not belong to the ocean or sea. For example, the term freshwater mollusk is mostly used by humans for creatures that occur near the shores of rivers and lakes. Also, the seashells found with tourist dealers and in shops contain different terrestrial and freshwater shells. These non-marine shells are not normally included as an example in shell collector's books. Some non-marine species are freshwater, pearly unionid mussel, the apple snail, and land snails. These creatures face constant challenges in their environment like extreme temperature, drought, flood, siltation, unidirectional flow of rivers, and predation.

Where do craft store seashells come from?

Seashells in the craft stores come from oceans, rivers, and lakes. Craft stores located near oceans largely use shells from beaches and other commercial in-land craft stores can use both freshwater shells and shells from the ocean water.

Decorative keepsakes of the 19th-century 'Sailor's Valentines' were made in the Caribbean and were frequently bought by sailors to give to loved ones when they returned home. Small seashells were elaborately arranged and glued creating beautiful designs in symmetry that would be encased in a frame made of wood, usually in the shape of an octagon. Some of them included meaningful expressions spelled out in the designs or heart-shaped designs. This type of shell-craft is also an Aboriginal women's practice of La Perouse, Sydney, and dates back to the 19th century. Shell-craft was used to make jewelry boxes, landmark replicas, and baby shoes. This Aboriginal women's practice was later adapted and tailored for the market of tourists and is currently considered high art in tourist spots.

Small shell pieces that were iridescent and colorful were chosen to make inlays and mosaics for decorating boxes, furniture, and walls. Whole shells have also been used in huge numbers for creating patterns to fit mirrors, man-made grottos, and pieces of furniture. Used not only in art, seashells that occur in backwaters and creeks are also used as additives to feed poultry by mixing the crushed shells with dry fish and jowar maize. Seashells have also been used to make necklaces, musical instruments, earrings, rings, hair combs, and belt buckles. Even sand itself is made of shells and the skeletons of marine species.

Here at Kidadl, we have carefully created lots of interesting family-friendly facts for everyone to enjoy! If you liked our suggestion for Where do seashells come from? Interesting mollusks animal facts then why not take a look at When do men stop growing? Curious body growth facts to know, or When do tulips bloom? Beautiful flower facts on bloom times?


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