Changes

[[image: A seal.jpg|thumb|250px|right|A Seal in water, demonstrating the insulating properties of blubber]]

[[image: A seal.jpg|thumb|250px|right|A Seal in water, demonstrating the insulating properties of blubber]]

If this insulating layer of air is replaced by water, heat is readily lost from the skin's surface, leading to a decrease in core body temperature and ultimately '''hypothermia'''.  The layer is protected by secretions from the skin onto the fur or feathers.  In birds, secretions from the [[The Integument of Exotic Species - Anatomy & Physiology#Avian Skin|uropygial gland]] maintain the water repellant properties of the plumage.  In mammals that are regularly exposed to water, a thick layer of subcutaneous adipose tissue of '''blubber''' is present as the insulating air is completely lost and replaced by water.

If this insulating layer of air is replaced by water, heat is readily lost from the skin's surface, leading to a decrease in core body temperature and ultimately '''hypothermia'''.  The layer is protected by secretions from the skin onto the fur or feathers.  In birds, secretions from the [[Integument of Exotic Species - Anatomy & Physiology#Avian Skin|uropygial gland]] maintain the water repellant properties of the plumage.  In mammals that are regularly exposed to water, a thick layer of subcutaneous adipose tissue of '''blubber''' is present as the insulating air is completely lost and replaced by water.

===Shivering===

===Shivering===