Composite images of Saturn’s rings, taken by NASA’s Hubble Space Telescope, have revealed mysterious color variations that hint that the rings could be made of materials from the outer solar system.

One of the curious things in the world of birds is why most species come in only one color form, while others come in many. We can start with the western tanager. Adult males all look the same. Adult ...

Lingering question: Do variations in scent correspond to variations in color? Spring weather in Boulder is difficult to predict because it seems that it is not a time of gradual warming but rather ...

Flower colour variation is a fundamental trait in angiosperms, serving not only to enhance the visual appeal of flowers but also to mediate interactions with a wide range of pollinators. The diversity ...

What color is a tree, or the sky, or a sunset? At first glance, the answers seem obvious. But it turns out there is plenty of variation in how people see the world—both between individuals and between ...