J.E. Shields schrieb: > So far as I can recall, female butterflies find the larval food plants on > which they lay their eggs by some combination of senses, including odor and > "taste" (if you call it "tasting" with their feet). > > While moths find nocturnal nectar sources mainly by odor, I think > butterflies locate their diurnal nectar sources mainly by sight -- again, > if I recall things from the past correctly. I never was an entomologist, > but as a kid I had intended to become one. > > Jim, your memory is still good, but more has been learned in between. Most insects have excellent form and colour differentiation, which they use to identify food sources (which is why they easily spot whole fields of their favourite crops!) As already mentioned, like birds, they see a much wider range of the spectrum as humans and are drawn to patterning in blossoms that we see as monochrome. White blossoms may actually have strong patterns in the ultraviolet spectrum. Interestingly, most red blossoms are avian pollinated, which would lead one to beleive insects cannot or do not associate this colour with food. Red flowers are rarely scented, although the foliage may be in order tp protect it. Scent is extremely important to butterflies and moths, both of which have quite elaborate antennae, especially the noctunal forms. Interestringly, birds have a very weak sense of smell, if any, and are drawn by colours and, of course, shapes. It has been theorized that certain flowers show distinguishing patterns in the UV range, that communicate things such as ripeness, available nectar, etc. Not yet proven to my knowledge. As to a birds colour vision, it is known that, with their 4 optical receptors, they distinguish very elaborate patterns in plumage, that we are unable to see. This explains why they can tell the male from the female visually, when we cannot. Also, many birds, especially in the groups of the Trochilidae (Hummingbirds) and Nectarinidae (sun birds), have evolved along with their food plants and are very specific; swordbilled Hummingbirds with Heliconias and Brugmansia sanguinea, Sunbirds with Aloes. Of course, most of us have heard of the moth with the 12" probiscis that Darwin predicted must exist in order to take advantage of the nectar found in the 12" tube of Angraecum sesquipedale (Orchidaceae). I have found that mints (Mentha, Nepeta, etc), in particular, attract butterflies. Stinging nettles are an important food source for caterpillars of many European species, much as the milkweed is in North America. Coneflowers are attractive to a degree, but, as they are not European natives, they may have a better reception in their native North America. Ciao, Jamie V. Cologne