the genus ocimum l. belonging to family of lamiaceae is widely distributed in iran, ocimum sanctum l. is described in many medicinal properties and a wide therapeutic range. it is used specially in the management of cough, ashtma, fever and common cold. in this research, samples were collected from shahr-e-rey, on august 2013, then essential oils were extracted by  hydro-distillation and steam ...

Colour signals are a major cue in putative pollination syndromes. There is evidence that the reflectance spectra of many flowers target the distinctive visual discrimination abilities of hymenopteran insects, but far less is known about bird-pollinated flowers. Birds are hypothesized to exert different selective pressures on floral colour compared with hymenopterans because of differences in th...

The genus Ocimum L. belonging to family of Lamiaceae is widely distributed in Iran, Ocimum sanctum L. is described in many medicinal properties and a wide therapeutic range. It is used specially in the management of cough, ashtma, fever and common cold. In this research, samples were collected from Shahr-e-Rey, on August 2013, then essential oils were extracted by  hydro-distillation and steam ...

Recent research has shown that nectar properties of flowers pollinated by generalist avian nectarivores differ markedly from those of flowers pollinated by specialist avian nectarivores. In particular, flowers pollinated by generalist avian nectarivores tend to have very dilute nectar dominated by hexose sugars. To establish whether pollinator-mediated selection can explain these traits, we tes...

The visual splendor of many diurnal flowers serves to attract visually guided pollinators such as bees and birds, but it remains to be seen whether bat-pollinated flowers have evolved analogous echo-acoustic signals to lure their echolocating pollinators. Here, we demonstrate how an unusual dish-shaped leaf displayed above the inflorescences of the vine Marcgravia evenia attracts bat pollinator...

Biological constraints and neutral processes have been proposed to explain the properties of plant-pollinator networks. Using interactions between nectarivorous birds (hummingbirds and flowerpiercers) and flowering plants in high elevation forests (i.e., "elfin" forests) of the Andes, we explore the importance of biological constraints and neutral processes (random interactions) to explain the ...

Simultaneous recordings of oxygen consumption and wing kinematics were collected from hummingbirds hovering at artificial flowers of different dimensions or when loaded by the addition of small weights to simulate increased fat stores. Hovering at widediameter flowers required increased wingbeat frequencies to compensate for decreased wingbeat amplitude, and it was 5% more metabolically expensi...

Strips of fallow vegetation along cropland borders are an effective strategy for providing brood habitat for declining populations of upland game birds (Order: Galliformes), including northern bobwhite (Colinus virginianus), but fallow borders lack nectar-producing vegetation needed to sustain many beneficial insect populations (e.g., crop pest predators, parasitoids, and pollinator species). P...

Floral nectar is offered by plants to animals as a reward for pollination. While nectar is typically a clear liquid containing sugar and trace amounts of amino acids, colored nectar has evolved in several plant families. Here we explore the functional significance of the phenolic compounds that impart a dark brown color to the nectar of the South African succulent shrub Aloe vryheidensis. Flowe...

Diurnal visitors to the flowers of many native plant species were identified in a wide range of Tasmanian sclerophyllous vegetation between September 1996 and April 1997. These foraging profiles were analysed to determine whether they were characteristic of various floral morphologies in predictable ways. It was found that although visitor profiles were sometimes consistent with classic pollina...