Camouflage there is no background, the principal methods of camouflage are transparency, silvering, and countershading, while the ability to produce light is among other things used for counter-illumination on the undersides of cephalopods such as squid. Some animals, such as chameleons and octopuses, are capable of actively changing their skin pattern and colours, whether for camouflage or for signalling. It is possible that some plants use camouflage to evade being eaten by herbivores. Military camouflage was spurred by the increasing range and accuracy of firearms in the 19th century. In particular the replacement of the inaccurate musket with the rifle made
Self-decoration camouflage materials including moulted cuticle and their own droppings, which appears to serve both to camouflage the larvae and to repel predators. Larvae of species that eat aphids decorate themselves with the waxy material produced by the aphids; larvae decorated like this are ignored by ants which farm the aphids, whereas the ants eject undecorated larvae, making this a wolf in sheep's clothing strategy of aggressive mimicry. The strategy has been used by traditional human hunters, such as when Australian aborigines dressed in emu skins and adopted emu-like postures to hunt these birds. Snipers, working alone, rely heavily on effective camouflage.