Spider are apparently absent. In some species, the exocuticle of the legs and prosoma is modified by a tanning process, resulting in brown coloration. Bilins are found, for example, in "Micrommata virescens", resulting in its green color. Guanine is responsible for the white markings of the European garden spider "Araneus diadematus". It is in many species accumulated in specialized cells called guanocytes. In genera such as "Tetragnatha", "Leucauge", "Argyrodes" or "Theridiosoma", guanine creates their silvery appearance. While guanine is originally an end-product of protein metabolism, its excretion can be blocked in spiders, leading to an increase in its storage. Structural colors
The Unicorn in the Garden 1950 film "Harvey" contains a scene depicting characters at a psychiatrist's office, where Veta is committed to the institution instead of Elwood. Dr. Richard Lenski, leader of the "E. coli" long-term evolution experiment, made an allusion to the story in a widely disseminated response to Conservapedia founder Andrew Schlafly (who expressed doubt Lenski found an evolutionary beneficial mutation in "E. coli" bacteria): "In other words, it's not that we claim to have glimpsed 'a unicorn in the garden' – we have a whole population of them living in my lab!" The of the TV series "Life on Mars" has similarities