Suddenly her eyes shot open before she gained a big smile on her face. "Oh what am I happy I paid some attention in biology when it was about genes. It is highly possible that the change of my iris color is caused by the change of genes. It is rare that it happens but it is possible," the mare explained to herself. Rarity was more than happy that there were reasonable explanations for her changes. She let go a small sigh and closed her eyes again, trying to get some much needed sleep.