What's the deal with floppy cat ears?

The main reasons for floppy cat ears can be attributed to the following:

Celtic fold gene expression: This is a genetic trait common in cats with folded ears, resulting from a dominant gene.
Poor cartilage development: If a cat's ears do not stand up properly, it could be due to inadequate development of the ear cartilage.
Calming signals: A cat with drooping ears is often trying to convey a calming message, hoping to avoid potential harm and to encourage the other party to stay away.
Illness: For example, ear mites or ringworm infections can cause severe discomfort in the ears, leading to the ears hanging down.

Normally, except for cats with folded ears, all other cats have upright ears. If a cat's ears suddenly droop, it's best to consult a veterinarian promptly.

Celtic fold gene expression:

Kittens usually start to stand up their ears at around 3 months old. If their ears droop at this stage, it could be a sign of Celtic fold gene expression. They may develop limb deformities or limpness later in life.

Poor cartilage development:

If a cat has folded ears but doesn't have the Celtic fold gene, it could be due to a genetic bone defect. This leads to incomplete development of the ear cartilage, which can cause stiffness in the tail, foot deformities, and swollen joints.

Calming signals:

A cat with drooping ears is usually sending out a calming signal. For example, if a cat owner makes a motion to strike it, the cat will drop its ears and back away. Additionally, when a cat is involved in a fight with another animal, it will also droop its ears. This is both an instinctive protection mechanism and a calming signal to avoid harm.

Illness:

If a cat has drooping ears along with symptoms like lethargy and loss of appetite, it could be sick. For instance, ear mites or ringworm infections can cause severe discomfort in the ears, leading to the ears hanging down. If you notice any abnormal behavior in your cat, take it to the vet immediately for diagnosis and treatment.