Scale (insect anatomy) and enable the insect to escape. (Forsyth 1992:12) Thomas Eisner tested spiderwebs' effectiveness by dropping various insects onto the webs. Moths were consistently able to escape, and all left impact spots where scales had stuck to the web. Eisner found these spots to be common. (Eisner 2003:218-220) Scales also help increase the lift to drag ratio in gliding flight. Successive close-ups of the scales of a Peacock wing Scale (insect anatomy) The presence of scales on the wings of Lepidoptera, comprising moths and butterflies, characterises this order of insects. The name is derived from Ancient Greek λεπίδος (scale) and πτερόν
Swallowtail butterfly species inhabit altitudes ranging from sea level to high mountains, as in the case of most species of "Parnassius". The majority of swallowtail species and the greatest diversity are found in the tropics and subtropical regions between 20°N and 20°S, particularly Southeast Asia, and between 20°N and 40°N in East Asia. Only 12 species are found in Europe and only one species, "Papilio machaon" is found in the British Isles. North America has 40 species, including several tropical species and "Parnassius". The northernmost swallowtail is the Siberian Apollo ("Parnassius arcticus"), found in the Arctic Circle in northeastern Yakutia, at altitudes