How Octopuses Change Colour — and What It Means for Colour-Changing Materials

Octopuses are among the most extraordinary creatures on Earth — able to change colour, pattern, and even texture in the blink of an eye. But this isn’t just a fascinating trick of nature. The same principles are used in modern colour-changing materials that respond to heat, light, and water.

Discover how nature’s most advanced colour-changing system has inspired materials that respond to heat, water, and light.

In this guide, we explore how octopus colour change works — and how similar effects can be recreated using liquid crystal sheets, thermochromic materials, and hydrochromic films.

How Do Octopuses Change Colour?

Octopus skin is made up of multiple layers that work together. Some layers contain pigments, while others reflect light to create shimmering colours. Combined, these systems allow the octopus to blend perfectly into its environment.

Pigment-Based Colour Change

The outer layer of the skin contains pigment cells that expand and contract. When expanded, they show strong colour. When contracted, they become almost invisible.

A similar effect can be recreated using thermochromic materials, which change colour when exposed to heat.

Structural Colour: Nature’s Hidden Trick

Beneath the pigment layer, octopuses use structure rather than colour. Light reflects off microscopic layers, creating vibrant colours that shift depending on conditions.

This is similar to how liquid crystal sheets work — reflecting specific wavelengths of light rather than using pigments.

Liquid Crystals and Temperature Colour Change

Liquid crystals respond to temperature changes, shifting through colours as heat increases. This makes them ideal for visual temperature indicators and interactive designs.

Hydrochromic Materials

Hydrochromic materials respond to water. When dry, they appear opaque. When wet, they become transparent — revealing hidden designs.

Explore hydrochromic films to create water-activated visual effects.

Side-by-Side Comparison

This comparison shows how natural biological systems and engineered materials achieve similar outcomes using different mechanisms.

Try It Yourself

If you want to explore these effects hands-on, the smart materials demonstration pack offers a practical introduction to multiple responsive materials.

Watch Octopus Colour Change in Action

Summary

Octopuses show us that colour is dynamic, responsive, and controlled. Modern materials bring these capabilities into real-world applications — from education to design and interactive products.