What is the difference between a clam, a cockle, a mussel, and a scallop?

What is the difference between a clam, a cockle, a mussel, and a scallop?

The clam, cockle, mussel, scallop, and even the oyster, are all marine bivalve molluscs. Bivalve means two valves.

They all have a shell structure, called a mantle, with two valves (two halves) and a ligament hinge with two adductor muscles that enable them to open and close.

All bivalves have light-sensitive cells that can detect light and motion, even though most do not have eyes. Giant clams have simple eyes on the edge of the mantle. Scallops have more complex eyes on the edge of the mantle – they have 10-100 eyes that each have a lens, a two-layered retina, and a concave mirror.

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Animal Ears: do big animals have big ears?

Do big animals have big ears and small animals have small ears? No, animal ears are many sizes and shapes.

Most ears have an outer ear (a pinna, a canal, and an eardrum), a middle ear, and an inner ear.

The pinna is the fleshy part that is visible. It is made of cartilage, not bone, so it is soft. It usually also has an ear lobe. The pinna directs sound through the canal to the eardrum.

The pinna has a muscle that moves the ear. For example, elephants and dogs can move their ears. Animals move their ears in the direction of a sound so that they can hear better.

Not all animals can move their ears because they have weak and non-functioning ear muscles. Animals that cannot move their ears include gorillas and monkeys. Humans cannot move their ears (without touching them).

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