Mollusks Facts

One of the most diverse groups of creatures on the planet is the mollusks. These invertebrates can vary in size, shape, and appearance and include many commonly known creatures such as snails, clams, and octopuses.

These animals can be found in a variety of habitats and thrive all over the world. The gastropods make up the largest percentage of the mollusks, up to 905 of the known species, and include clams and snails. 

Others, including bivalves like the oyster or mussel, are a favorite food of many cultures worldwide and are found in the majority of oceans, seas, and lakes. Most mollusks are vegetarians, with the exception of the cephalopods, which are carnivores.

This group of animals is among the longest living and most fascinating of the animal kingdom and provides many useful services to the world we live in today. For example, bivalves can help keep our waters clean free from pollution by filtering the water they live in while they collect their food by filtration. 

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Discover Interesting Facts About Mollusks

When studying the animal world, be sure to take some time to learn about mollusks, which are some of the most interesting, diverse, and complex animals in the world. They range in size from microscopic to up to 20 meters long, in the case of the giant squid.

They can also exhibit some unique characteristics, and some are even highly intelligent and capable of solving complex problems. Some interesting facts to know about mollusks both in the water and on land can include the following. 

Second largest phylum of invertebrates 

Mollusks are a phylum or classification of a group of animals sharing the same basic characteristics. These animals are invertebrates, meaning they don’t have bones and have a mantle and, in many cases, have an outer shell depending on the particular mollusk.

In this phylum, over 100,000 individual species and 85,000 recognized species make this the second largest phylum of all. This animal group has both aquatic and terrestrial species ranging from the octopus to a wide range of land-dwelling snails.

This phylum exhibits some of the greatest diversity among animal groups in the world. 

Some have shells, but others do not

One of the common characteristics of bivalves and some gastropods is a shell. These shells help to protect the animals inside from predators and other dangers they may encounter.

It serves as a type of exoskeleton or home and can come in a wide range of colors, patterns, and shapes. Some of the shells are prized for their beauty and shapes for making jewelry, arts and crafts, or for use in landscaping designs.

The most well known for uses in projects or art pieces are conch, oysters, clams, and mussels. In some cases, there is a snail-like creature without a shell known as slugs.

These animals can be found both in the water and on land and share many of the same snails’ characteristics. There are brightly colored slugs in the oceans that can sting or bite and others that are poisonous to potential predators. 

Some can live in the water, yet others are terrestrial 

Although there are many water-dwelling mollusks, there are plenty of terrestrial species as well. Perhaps the most common are the snails and slugs. Both can be found easily in milder climates all over the world.

Snails and slugs can be both aquatic and terrestrial, which makes them fascinating and diverse. Snails are a common choice for pets in aquariums because they are easy to care for and come in a wide range of shapes and sizes.

Many of the species found in pet stores are brightly colored and can make for interesting viewing in an aquarium. Terrestrial snails and slugs can be found looking for food around pet dishes and in moist, mild areas, especially around homes and garden areas.

Some people even eat certain snails, which can be referred to as escargot in French cuisine preparations. People interested in observing snails don’t have to go to the pet store, however, because most climates have wild snails that can easily be found and observed in moist, mild climates such as gardens and under bushes or flowerbeds. 

Mollusks with shells can produce pearls 

Pearls are hard luminous objects that are produced by the tissue inside a mollusk. The most popular of the pearls are created in the saltwater oyster. Humans can cultivate these pearls in pearl farms or be harvested in the wild by divers or oyster farmers.

The wild black pearls are perhaps the most sought after of the pearls, but the black cultured pearl can also fetch top dollar if they meet certain requirements set by certain pearl associations or gem societies dealing with this type of jewelry.

A pearl is created when an irritant, usually sand or something similar, finds its way into the mollusk’s shell, and the mollusk produces a coating to protect itself from the irritant.

Over time, the coating continues to build and creates a pearl. Some pearls can be quite large, depleting on the species and the amount of time the mollusk created it. 

Some mollusk shells were used as currency 

Native Africans used cowrie shells as currency for many centuries. Around the 14th century, other cultures became aware of their beauty and sought to import them for use in various applications. North American natives used shells to create a form of currency known as “wampum.”

Later, this wampum was used to create elaborate attire and art creations that were highly prized by various Native American cultures. Other mollusk shells used as currency by Native Americans included whelk shells, clams, and olive snail shells. 

Some mollusks sting or bite

Although many of the mollusks are harmless and rely on their shells for protection, some species can sting or bite to protect themselves from predators and other potential hazards in their environment.

Perhaps one of the most feared yet beautiful mollusks that can sting is the blue-ringed octopus. This mollusk can kill a human in some instances and should be avoided at all costs.

Others have a beak and can bit to either eat or to protect themselves when they feel threatened. 

Mollusks have a mantle

A mantle is a space in a mollusk that houses the repertory and sometimes the gastrointestinal system. This area secretes calcium carbonate in bivalves, which can assist with the creation of pearls.

These pearls are prized for their use in jewelry and can be created in both freshwater bivalves and saltwater bivalves. Pearls can come in a variety of shapes and colors, which make them very popular in jewelry applications all over the world.

Some mollusks use their mantle as a means of locomotions or in other words, they use it to propel themselves in the water. A prime example of a mollusk using its mantle for locomotion is the scallop, which migrates during certain times of the year by forcing water through its mantle to propel it through its habitat. 

Mollusks’ Incredible Defense and Intelligence

Mollusks are amazing creatures possessing uncanny abilities to blend into or protect themselves from predators and hazards found in their surroundings. Some of these species can create camouflage on demand, such as the cuttlefish and the octopus.

Their skin can change colors at will to blend into their surroundings as necessary and can recreate bright, vivid colors with complex patterns. While some can change their patterns and colors to match almost the entire visible spectrum, others have basic camouflage ability to keep them hidden from predators in their environment.

Some octopuses have also exhibited a high level of intelligence that rivals dolphins and other highly advanced creatures, both aquatic and terrestrial. 

Octopi has also been shown to be capable of solving complex problems and have thought to communicate with scientists in certain studies. These cephalopods can also communicate mostly through complex signals that have fascinated scientists over the years.

Another fascinating defense mechanism that some cephalopods possess is producing ink to confuse their predators and allow them to escape danger. Some of the most common examples are squid and octopus, which can quickly release dark black ink into the water, creating a view or cloud that obscures the view of an approaching predator.

Mollusks are truly unique and diverse and can prove to be some of the most interesting animals to study and learn about in school, whether it’s terrestrial species or aquatic species.