The following post was written by 2015 Grosvenor Teacher Fellow Rebecca Detrich during her expedition to the Galápagos Islands. The Grosvenor Teacher Fellow Program is a professional development opportunity made possible by a partnership between Lindblad Expeditions and National Geographic Education. (We’re accepting applications now!)

Red can be found on the back of a marine iguana, orange on the scales of a lava lizard. Yellow is found in the eye of the short-eared owl, green is the grass the giant tortoise consumes. And where better to find blue than on the foot of a blue-footed booby? But purple … well, purple is the hardest color to find in the Galapagos.

On each island I visited, I searched for the elusive color purple. My goal was to complete a photographic color collage to bring back to students at Westminster Woods in California.

Part of my work as an educator is to help students develop observation skills in the natural world. One introductory activity we use with younger students is a color scavenger hunt, where students search for various hues in nature. Students can look for matches to an individual square of color or try to find matches for the whole collage. Older students can use the collage as a model and create their own works of art—either looking for a rainbow of colors or shades of the same color. Using my Galápagos collage, I can help students make connections to nature, as well as connect the similarities of color from the Galapagos to the redwood forests of California.

While every color may or may not be found within the redwood forest or in your own home community, looking at the natural world through the lens of color is a simple invitation to look closely, to pay attention, and observe. The more we look, the more we see, and sometimes when we’re looking for colors in nature we end up seeing so much more.

Eventually, with the help of my fellow explorers, I did find the color purple in the Galapagos. We found purple in shells, in native flowers, and—most surprising of all—in the lilac hue of the eye of a Sally Lightfoot crab.

I invite you to explore with your students and see if you can find an orange similar to the color of a Nazca booby’s beak, a bluish-grey like that of a scalloped hammerhead shark, or a yellow similar to the pigment of a waved albatross’s feet. Maybe you’ll even have an easier time than I did finding the color purple.

Rebecca “Bec” Detrich is the Education Director at Westminster Woods, a residential environmental educational school in the redwoods of Sonoma County, California.