Simplify the following text for a Grade 5 native English-speaking person.
Original: Insulation is provided by fur between the spines , which ranges in color from honey to a dark reddish-brown and even black ; the underside and short tail are also covered in fur .
Simplified: They have fur between the spines , which ranges in color from honey to a dark reddish-brown and even black . The underside and short tail are also covered in fur .