Mammals: Characteristics and Body Structure

Mammals

Characteristics

• Warm-blooded (endothermic): regulate their own body temperature
• Hair or fur present at some stage of life
• Three middle ear bones (ossicles) for hearing
• Mammary glands for milk production in females
• Brain development: neocortex present, with a large cerebral cortex
• Dental structure: teeth differentiated into incisors, canines, and molars

Body Structure

• Skeletal system: diaphragm separates chest and abdominal cavities
• Respiratory system: lungs with alveoli for gas exchange
• Circulatory system: four-chambered heart with aortic arch
• Nervous system: complex brain structure with a large cerebrum

Reproduction and Development

• Viviparity: give birth to live young (except for platypus and echidna)
• Placenta: nutrient supply from mother to fetus during pregnancy
• Lactation: production of milk for young

Types of Mammals

• Monotremes: lay eggs, produce milk (e.g., platypus, echidna)
• Marsupials: give birth to underdeveloped young, then complete development in a pouch (e.g., kangaroo, koala)
• Placentals: give birth to fully formed young, with a placenta during pregnancy (e.g., humans, dogs, cats)

Characteristics of Mammals

• Mammals are warm-blooded, meaning they regulate their own body temperature
• Hair or fur is present at some stage of a mammal's life
• Mammals have three middle ear bones (ossicles) for hearing
• Females have mammary glands for milk production
• Brain development in mammals includes a neocortex and a large cerebral cortex
• Mammals have teeth differentiated into incisors, canines, and molars

Body Structure of Mammals

• The skeletal system includes a diaphragm that separates the chest and abdominal cavities
• The respiratory system features lungs with alveoli for gas exchange
• The circulatory system has a four-chambered heart with an aortic arch
• The nervous system has a complex brain structure with a large cerebrum

Reproduction and Development in Mammals

• Mammals give birth to live young, except for platypus and echidna
• The placenta supplies nutrients from the mother to the fetus during pregnancy
• Females produce milk for their young through lactation

Types of Mammals

• Monotremes lay eggs and produce milk, examples include platypus and echidna
• Marsupials give birth to underdeveloped young, then complete development in a pouch, examples include kangaroo and koala
• Placentals give birth to fully formed young, with a placenta during pregnancy, examples include humans, dogs, and cats

Characteristics of Mammals

• Mammals are warm-blooded, meaning they regulate their own body temperature
• They have hair or fur at some stage in their lives
• Mammary glands are present, which produce milk to feed their young
• Mammals have three middle ear bones (ossicles: malleus, incus, stapes) that aid in hearing
• They give birth to live young, with a few exceptions
• The neocortex region is present in the brain, which is responsible for higher-order thinking

Types of Mammals

• Monotremes are mammals that lay eggs, but also produce milk for their young (e.g., platypus, echidna)
• Marsupials give birth to underdeveloped young, which then complete development inside a pouch (e.g., kangaroo, koala)
• Placentals give birth to fully formed young, nourished by a placenta during gestation (e.g., humans, dogs, cats)

Mammalian Body Structure

• The skeletal system has a diaphragm that separates the chest and abdominal cavities
• Teeth are differentiated into incisors, canines, and molars
• Sweat glands and sebaceous glands are associated with hair follicles in the skin and hair

Mammalian Brain and Behavior

• Mammals have a large brain-to-body mass ratio, indicating high intelligence and complexity
• They possess advanced sensory systems, including sensitive vision, hearing, and smell
• Mammals exhibit complex social behavior, including communication and culture