* Hair: This is a defining characteristic of mammals. Hair provides insulation, camouflage, protection, and even sensory functions.
* Glands: Mammals have several types of glands in their skin:
* Sweat glands: Help regulate body temperature.
* Sebaceous glands: Produce oil to keep skin and hair lubricated.
* Scent glands: Used for communication, marking territory, and attracting mates.
* Thickness: Mammal skin is generally thicker than that of other vertebrates, providing better protection from the elements and injury.
Key Features:
* Epidermis: The outer layer of skin, responsible for waterproofing and protection.
* Dermis: The thicker, inner layer containing blood vessels, nerves, hair follicles, and glands.
* Hypodermis: A layer of fat beneath the dermis that provides insulation and energy storage.
Variations:
While all mammals have skin with these basic features, there are significant variations depending on the species and its environment. For example:
* Aquatic mammals: Have thicker skin and blubber for insulation in cold water.
* Desert mammals: Have thinner skin with fewer sweat glands to conserve water.
* Tropical mammals: Have more sweat glands to help them stay cool.
Ultimately, the specific characteristics of a mammal's skin are adapted to its unique lifestyle and habitat.