Insect pollinated flowers produce nectar to attract insects , which visit these flowers for nectar only. These insects feed on nectar. While feeding on nectar insects carry pollen along with their bodies and when they visit another flower they affect pollination. In these flowers nectar is produced at a position that when an insect collects nectar, its body comes in contact with pollen and stigma also.

Images of a Mimulus flower in visible light (left) and ultraviolet light (right) showing a dark nectar guide that is visible to bees but not to humans

Nectar guides are markings or patterns seen in flowers of some angiospermspecies, that guide pollinators to their rewards. Rewards commonly take the form of nectar, pollen, or both, but various plants produce oil,

[1]

resins,

[2]

scents,

[3]

or waxes. Such patterns also are known as pollen guides and honey guides, though some authorities argue for the abandonment of such terms in favour of floral guides(see for example Dinkel & Lunau

[4]

).

These patterns are sometimes visible to humans, for instance, the Dalmatian toadflax(Linaria genistifolia) has yellow flowers with orange nectar guides.

[5]

However, in some plants, such as sunflowers, they are visible only when viewed in ultraviolet light. Under ultraviolet, the flowers have a darker center, where the nectaries are located, and often specific patterns upon the petals as well. This is believed to make the flowers more attractive to pollinators such as honey bees and other insects that can see ultraviolet. This page on butterflies shows an animated comparison of black-eyed Susan (Rudbeckia hirta) flowers in visible and UV light.

The ultraviolet color, invisible to humans, has been referred to as bee violet, and mixtures of greenish (yellow) wavelengths (roughly 540 nm

[6]

) with ultraviolet are called bee purple by analogy with purple in human vision.

In viola tricolour ( Pansy) petals bear striations as nectar guides, which attract insects and guide them towards nectar. While moving in flower to suck nectar these insects bring about pollination.

Flower of Pansy showing petals bearing a distinct pattern , which act as nectar guides.

Perché si va a lavorare?

Gli insetti lo fanno per essere pagati... il nettare nel loro caso.

Alcuni fiori non hanno nettare, ingannano gli insetti solo imitando altri che lo hanno o imitando i compagni (per aspetto e odore). Ma questo non funziona se gli insetti lo capiscono, allora smettono di venire. Naturalmente i maschi continueranno spesso ad essere attratti da quelle che pensano siano potenziali compagne (porno, bambole di plastica, orchidee).

I fiori impollinati dalla mosca puzzano di carne in decomposizione, le mosche vengono a cercare carne morta e finiscono per portarsi via il polline.