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Secrets of the Seashell

If you have ever collected seashells, you know that they come in a wide range of shapes and colours. But why is that? Many things help decide a shell’s appearance, including where it is formed and how it is used for protection.

To understand a shell’s appearance, it’s important to first understand what shells are. Most seashells are the exoskeletons of different kinds of molluscs, such as snails, clams and oysters. An exoskeleton is an animal’s hard outer covering. As a mollusc grows, it uses chemicals from the sea to produce a compound of calcium, which becomes the hard exoskeleton. The exoskeleton shields the mollusc’s soft, slimy body. When the mollusc dies, its soft body rots away or is eaten by a predator. Its exoskeleton may wash to the shore, where people call it a seashell.

A seashell’s appearance is affected by its environment. For example, warmer waters tend to produce more colourful seashells. This is partly because warm waters contain more food sources for molluscs. The foods contain different pigments, substances that give them their colour. Since molluscs in warmer waters eat foods with many different pigments, they create more colourful exoskeletons. Molluscs found in colder waters have a more limited food supply. Therefore, their exoskeletons tend to be darker and more uniform in colour.

The main role of a mollusc’s exoskeleton is to protect the mollusc inside. So, a shell’s thickness and shape depend on how it is used for protection. Thin shells are lighter than thick shells. Thus, molluscs that avoid predators by swimming away often have thin shells. The shell’s light weight allows the mollusc to move around more easily. To make up for their thinness, these shells often have spikes and ridges to give them more strength. In addition, the spikes and ridges give the mollusc extra protection against predators. molluscs that burrow underground, like clams, also have thin shells so they can dig quickly. These molluscs have smooth shells, however, since predators cannot easily get to them underground. Finally, some molluscs form thick, heavy shells to deter predators. These heavy shells are difficult for predators to break through, and they also help anchor the molluscs to surfaces like rocks and mud.

Every seashell was once a mollusc’s home. Each seashell was built differently in order to suit the creature living inside. These animals create shells that give them the best chance of living safely in their environments.