These stunning insect close-ups reveal dazzling bug complexity
Hard yet flexible, chitin builds insects’ exoskeletons, wings, and scales.
Arthropods are the most diverse group in the animal kingdom. Among them, the evolutionary record holders are the insects, thanks to their ability to adapt to many different ecosystems both in water and on land. The versatility of arthropods is due in large part to chitin, a substance that forms their hard outer covering as well as their wings and other flexible parts. Like cellulose, the building block of plant cell walls, chitin is made of glucose molecules, but it also contains nitrogen, producing a firm structure.
Chitin is the main component of the arthropod’s exoskeleton, the first rigid form to evolve in multicellular organisms: arthropods made chitin as early as 550 million years ago. Secreted by the epidermis, or skin-like, soft outer layer, chitin combines with other compounds to form the waxy, water-repellant cuticle.
A remarkably hard yet flexible material, chitin strengthens insect mandibles to cut through rock and metal, and provides elasticity between the stiff body segments, enabling speed and agility. The tiny, delicate scales covering insects such as butterflies also contain chitin. It’s integral to the thin tracheal tubes that make up their respiratory system and the hairs that collect pollen.
It seems chitin can do almost anything—except allow an exoskeleton to expand. So, in order to grow, arthropods must molt. Every so often they have no choice but to temporarily shed their protective chitinous covering in exchange for a little bit of room to grow.
Related Topics
You May Also Like
Go Further
Animals
- Behind the scenes at America’s biggest birding festivalBehind the scenes at America’s biggest birding festival
- How scientists are piecing together a sperm whale ‘alphabet’How scientists are piecing together a sperm whale ‘alphabet’
- Orangutan seen using plants to heal wound for first timeOrangutan seen using plants to heal wound for first time
- What La Palma's 'lava tubes' tell us about life on other planetsWhat La Palma's 'lava tubes' tell us about life on other planets
Environment
- The northernmost flower living at the top of the worldThe northernmost flower living at the top of the world
- This beautiful floating flower is wreaking havoc on NigeriaThis beautiful floating flower is wreaking havoc on Nigeria
- What the Aral Sea might teach us about life after disasterWhat the Aral Sea might teach us about life after disaster
- What La Palma's 'lava tubes' tell us about life on other planetsWhat La Palma's 'lava tubes' tell us about life on other planets
- How fungi form ‘fairy rings’ and inspire superstitionsHow fungi form ‘fairy rings’ and inspire superstitions
History & Culture
- This thriving society vanished into thin air. What happened?This thriving society vanished into thin air. What happened?
- These were the real rules of courtship in the ‘Bridgerton’ eraThese were the real rules of courtship in the ‘Bridgerton’ era
Science
- Is the 5-second rule true? Science finally has an answer.
- Science
- Gory Details
Is the 5-second rule true? Science finally has an answer. - E-bikes are good for the environment—but what about your health?E-bikes are good for the environment—but what about your health?
- Why trigger points cause so much pain—and how you can relieve itWhy trigger points cause so much pain—and how you can relieve it
Travel
- The best LGBTQ-friendly destinations for every travelerThe best LGBTQ-friendly destinations for every traveler
- 6 of the best active pursuits on Cape Cod and the Islands
- Paid Content
6 of the best active pursuits on Cape Cod and the Islands - The key to better mindfulness may be your public gardenThe key to better mindfulness may be your public garden