Hello Dear,

There are only three characteristics unique to mammals. The three characteristics are mammary glands, hair and three middle ear bones. Other characteristics often thought to be unique to mammals are found in other species including birds, insects and reptiles. They have mammary glands that help them produce milk to feed their younger ones. Presence of region of the brain known as Neocortex. Their skin possesses oil glands (sebaceous glands) and sweat glands (sudoriferous glands).

Characteristics of Mammals

• Sweat glands.
• Glands specialized to produce milk, known as mammary glands.
• A neocortex region in the brain, which specializes in seeing and hearing.
• Specialized teeth.
• A four-chambered heart.

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