It is believed that a mink-like animal with a long body and short legs was the ancestor of the gray wolf. In the two photographs, a gray wolf is shown on the left, and the modern mink is shown on the right.%0D%0A%0D%0A%0D%0A%0D%0A %0D%0A%0D%0A a%0D%0AThey had different methods for sexual reproduction.%0D%0A b%0D%0AThey were exposed to different environmental factors.%0D%0A c%0D%0AThey had different traits passed on to them through natural selection.%0D%0A d%0D%0AThey had genetic variation because of generations of sexual reproduction.
