Shades of Nature

For nearly 400 million years, evolution has shaped the amazing diversity of color in insects. Whether flashy, iridescent, subtle or cryptic, their colors are more than just beautiful. Some insects have bright colors to attract mates or to warn predators they are harmful. Others are masters of deception and use colors to blend in, whether to hide from enemies or ambush their prey. These adaptations can determine whether an insect gets eaten or lives long enough to reproduce and pass on these traits to its offspring.

Pulchriphyllium giganteum
Malaysian leaf insect

There’s More to Color Than Meets the Eye

How insect colors are produced is complex, but the two basic mechanisms are from pigments and from structural features of the exoskeleton. Chemical properties of pigments determine which wavelengths of light are absorbed and which colors are reflected. Structural colors are produced in various ways by how nanoscopic structures on the surface of the insect interfere with light.

Chrysochroa sp.
jewel beetle

Multilayer Reflections

Ultrathin layers of chitin in these insects selectively reflect different wavelengths of light. Their color depends on layer thickness, the spacing between them, and the angle of light.

 

TEM cross section of cuticular reflectors. From T. D. Schultz, 19

Heterorrhina sp.
flower chafer

Most blues are structural color, like in the Morpho butterflies, which have layers of tree-like branches that reflect blue.

Morpho sp.

(Left) The brightness of  the color is due to six to ten branches on each tiny tree.  (Right) Ridges on wing scales are made up of rows of tree-like nanostructures that contribute to the blue color. From P. Vukusic et al. 1999.

 

Gyroid-type photonic crystal reflections

The sparkling gem-like color these insects have are produced by an intricate network of three-dimensional nanoscopic spheres called photonic crystals. They are in the interior of flattened scales covering the body and optically interfere with light.

Opalescent scales on weevil (left). Closeup of scale structures (right). From Welch & Vigneron, 2007.

Eupholus spp.
weevil

Chemical pigments

Chemical pigments like melanins, ommochromes, and carotenoids give insects their black, brown, red, orange, and yellow colors, and some shades of green.

Zerene eurydice
California dogface butterfly

Pyrops pyrorhyncha
red nose clown lanternfly

 Heliconius sp.
longwing butterfly

The art of Deception: Camouflage and Disguise

Colors help insects blend into their background making it harder for predators like birds, lizards, and even other insects to see them Some have even evolved shapes and color patterns that look like leaves or twigs. Startling displays of colors or patterns can momentarily confuse or distract a predator, giving them time to escape.

 

Pulchriphyllium giganteum
Malaysian leaf insect

In addition to being well camouflaged, this insect sways like leaves on a wind-blown plant suggesting it can adjust behavior based on environmental cues.

Kallima sp.
dead leaf butterfly

This butterfly has evolved the appearance of leaf veins, margins, and decay spots to hide in plain sight among dead leaves.

Caligo sp.
owl butterfly

Patterns that resemble large predator eyes can make a defenseless insect appear bigger and more fearsome. Can you also see the profile of a snake’s head?

Cithaerias pireta
rusted clearwing-satyr

The reduced number of scales and nanoscopic anti-glare properties which make the wings translucent help this butterfly blend in with the background. 

Mantidae

Ambush predators like mantids can look like leaves, twigs, and flowers to hide from unsuspecting prey. They can escape becoming prey themselves by flashing colorful spots on their wings which startles predators.

 Iris oratoria
Mediterranean mantid

 

I’m Warning You: Aposematism and Mimicry

Bright contrasting colors like red and black, orange and black, or yellow and black advertise to potential predators that an insect tastes bad or may bite or sting. These visual warning signals are called aposematic coloration. Some insects without anti-predator defenses of their own can mimic the look, sound, and behavior of those that have strong chemical or physical defenses.

Aposematism

A great diversity of insects display warning coloration that helps protect them from being preyed upon. Nocturnal insects with black and white patterns can also signal they should be avoided.

Pharypia pulchella
stink bug

Lycorma delicatula
spotted lanternfly

Dactylotum bicolor
rainbow grasshopper

Pepsis sp.
tarantula wasp

Dasymutilla spp.
velvet ant

Mullerian Mimicry

Unrelated species colors and patterns warn predators they have strong physical or chemical defenses.

Danaus plexippus / Limenitis archipppus archippus
monarch butterfly / viceroy butterfly

 

Batesian Mimicry

Harmless insects like this moth and beetle, imitate insects that taste bad, bite, or sting, like this bee.

Bombus sp. / Hemeris diffinis
bumble bee / hummingbird moth [mimic]

Ulochaetes lioninus
lion beetle [mimic]

See our exhibit live in the Valley Life Science Building’s first floor, located in the hall south of the Tyrannosaurus rex skeleton.  

For building open hours and dates please check here.

 

To see what went into creating this exhibit see the Making of Shades of Nature page.

Exhibit design and text by Roberta Brett
Exhibit graphics by Eliza Anker
Photos and webpage by Sloane Sim
Exhibit collaborators – Anna Hatzakis, Hugo Sappington, Amy Zheng

Additional materials:
Cuticular reflectors (T. D. Schultz, 1985)
Structural Color (P. Vukusic et al. 1999)
Opalescent weevil scales (Welch & Vigneron, 2007)