Dogs and cats have highly developed emotional bodies, with less developed mental levels. They feel, and feel deeply, although they may not always understand just what they problem is or why something has happened to them. When the human they have bonded with suddenly leaves or dies, or when an animal friend moves away or dies, a pet can be overwhelmed with grief. If the cat of dog must then adjust to living with a new family, they grief, confusion and emotional upset are increased. If the animal suddenly finds herself in a shelter ans all alone, she may experience pain that becomes difficult to heal in the most caring new home. Dogs and cats experience anger, depression, apathy, lethargy, loss of the will to live, fear, terror, and may also place blame on others rightly or not. Where understanding of causes is limited, these emotions can be worsened and acted out in negative behaviors. Dogs bond totally and for life. Cats, who are more loners and place oriented, are less sociable. They react deeply to stress and change.