The eggs came from black mice, while the foster mothers were all white mice. The baby mice all came out coffee-colored, the color of their identical DNA mother.

• 卵子来自黑色的老鼠，而养母全部是白色的老鼠，幼鼠的毛色却均为咖啡色，正是提供它们DNA的母亲的毛色。