As some of you may know, Holly's Jingle (broken tort), still has ears straight up, while his brother, Holly's Ronald (blue), has ears that are mostly lopped. Why? They both seem to have the same width to their crown...but Jingle's are much longer and heavier. You'd think they would be lopped already.
Which led me to this....
Playing outside with the bunnies yesterday, I noticed that Ronald soaks up the sun quickly because of his darker color. He's blue, and dark colors soak in warmth and light (which is why you wouldn't wear black on a warm day). Whereas Jingle is mostly white, which repels heat and light. Since the warmth is what helps the ears to drop, maybe Ronald's are dropping before Jingle's because of this?? Just my thought. It would be interesting study if anyone wants to pursue it.