Orchidaceae tubers after detecting the plants underground by scent. Orchids have been used in traditional medicine in an effort to treat many diseases and ailments. They have been used as a source of herbal remedies in China since 2800 BC. "Gastrodia elata" is one of the three orchids listed in the earliest known Chinese Materia Medica ("Shennon bencaojing") (c. 100 AD). Theophrastus mentions orchids in his "Enquiry into Plants" (372–286 BC). Orchids have many associations with symbolic values. For example, the orchid is the City Flower of Shaoxing, China. "Cattleya mossiae" is the national Venezuelan flower, while "Cattleya trianae" is the
Flower constancy more dissimilar, for example in their coloration. When, in a community of flowering plants, the flowers are all similarly colored, the constancy is often lower because different species are more difficult to distinguish, whereas constancy tends to be higher when the flowers are distinctly differently colored. Flower constancy benefits flower pollination but, arguably, constancy is not so obviously adaptive for pollinators. Individuals that show constant behavior ignore other flowers that could potentially provide more nectar (reward) than their preferred type. As a result, flower constancy seems to contradict optimal foraging models, which assume that animals will move minimal distances between