You Have Discovered a New Species of Rodent in a Remote

You have discovered a new species of rodent in a remote forest.You manage to trap a handful of the animals and bring them back to your lab to establish a breeding program for study.All of the rodents have smooth cup-shaped ears, but as you breed successive generations, you also notice individuals with notched ears, ones with serrated ears, and ones with long floppy ears.Genetic tests establish that there is only one gene involved, so you infer that the genetic phenomenon responsible is _______.