What is a layered structure?
A layered structure is composed of material(s) organised in layers or thin sheets, one on top of another.
Material scientists use the term lamina to describe a layer. Two or more layers of material fixed together make a laminate (a material made up of layers permanently bonded together) to engineer materials that demonstrate combined properties of their components.
Layered structures in biology
Layers in textiles
A laminated or combined fabric is a material composed of two or more layers, at least one of which is a textile fabric, bonded closely together by means of an added adhesive or by the adhesive properties of one of more of the component layers.
Laminated textiles are commonly found in outdoor active garments and are used to combine breathability with water resistance in lightweight synthetic outer wear.
Tightly woven polyester textiles are lightweight and can be breathable but are not water resistant. Teflon membranes such as Gore-TexTM are typically bonded onto the back of an outerwear polyester textile to provide water resistance.
Other techniques for creating and combining two distinct layers of textile material are double cloth (knitted or woven), quilting, patchwork etc...
Layered structures aid
Consider diabolical ironclad beetle…
The Phloeodes diabolicus otherwise known as the diabolical ironclad beetle is known for being incredibly strong and able to withstand heavy loads that would prove fatal to most insects. This is because its shell is so tough, even to the degree that when put it on display in a museum it requires a drill to create the hole in the shell to insert the pointed edge stainless steel pin.
The strength of the shell is due to the layered design of the structure. Studies of the elytra (forewing) revealed a multi-layered cuticle made from chitin fibres held together by a protein-based glue. The outer layer is composed of fibres oriented in different directions. The inner cuticle is composed of layers of thicker chitin fibres that run in parallel to each other, these layers are separated by a series of column type structures that run from the inner cuticle towards the outer layer, bonding the structure together.
It is the combination of these layers that make the beetle shell so impressively strong.