Medically reviewed by Johnstone M. Kim, MD Key Takeaways Gray and green eye colors are the rarest in the world.Eye color is ...

Eyes, those fascinating windows to our souls, are also incredibly varied. From a vibrant blue to a warm brown, each shade seems to have its own story to tell. Of all the colors that exist, one shade ...

Your genetic make-up determines a wide range of physical traits, and eye and hair color are among the most visible. Many people inherit shades that are common across the globe, such as brown eyes or ...

The mesmerizing colors of human eyes—from deep browns to vibrant blues, subtle greens, and rare ambers—result from intricate genetic factors that influence melanin production in the iris. This same ...

When it comes to dog's coats, merle one of the most jaw-dropping color patterns around. Also known as "dapple," the end result looks like a breathtaking splatter painting—irregular splotches of dark ...