A long-standing paradigm in biology has been that hummingbirds and passerine birds select for different nectar properties in the plants they pollinate. Here we show that this dichotomy is false and a more useful distinction is that between specialized and generalized bird pollination systems. Flowers adapted for sunbirds, which are specialized passerine nectarivores, have nectar similar to that...

Animals organize their lives around circannual and circadian rhythms, but little is known of their use of much shorter intervals. In the laboratory, some animals can learn the specific duration (seconds or minutes) between periods of food access. It has been supposed that wild nectarivores, such as hummingbirds, might also learn short time intervals so as to avoid revisiting emptied flowers unt...

The avian plumage color gamut is the complete range of plumage colors, as seen by birds themselves. We used a tetrahedral avian color stimulus space to estimate the avian plumage color gamut from a taxonomically diverse sample of 965 plumage patches from 111 avian species. Our sample represented all known types of plumage coloration mechanisms. The diversity of avian plumage colors occupies onl...

Native plant species that have lost their mutualist partners may require non-native pollinators or seed dispersers to maintain reproduction. When natives are highly specialized, however, it appears doubtful that introduced generalists will partner effectively with them. We used visitation observations and pollination treatments (experimental manipulations of pollen transfer) to examine relation...

For those who are not familiar with birds as experimental animals perhaps it should be pointed out that they offer many advantages over mammals, although they are obviously not the ideal animal for certain experiments. Few laboratories work with birds other than poultry, but canaries and other cage birds are occasionally used when their special qualities are applicable, as in work with low conc...

Abstract: Flowers provide birds with a range of dietary resources, although few data are available on flower eating for that have mixed diets. We report here new food type the Blue-crowned Trogon (Trogon curucui), describing two events. The individuals fed yellow trumpet tree flowers (Handroanthus spp.) at peak dry season in Cerrado and Pantanal biomes. picked up by sally-glean flying brief hov...

One floral characteristic associated with bat pollination (chiropterophily) is copious pollen production, a pattern we confirmed in a local comparison of hummingbird- and bat-adapted flowers from a cloud forest site in Ecuador. Previous authors have suggested that wasteful pollen transfer by bats accounted for the pattern. Here we propose and test a new hypothesis: bats select for increased pol...

Matches between the bills of hummingbirds and the flowers they visit have been interpreted as examples of coadaptation and feeding specialization. Observations of birds feeding at flowers longer or shorter than their bills combined with a lack of experimental evidence for foraging trade-offs, however, fail to support these interpretations. We addressed these inconsistencies by considering a sel...

Animal pollination is an important and highly valued ecosystem function the role of birds as pollinators increasingly acknowledged. However, such interactions can be challenging to document often require extensive field programs. Over last decade, environmental DNA (eDNA) has been analyzed from several different contemporary sample types, water, soil, flowers, air. The applications these studie...

The Himalayan endemic alpine genus Roscoea, like other members of ginger family, exhibits the combination of floral traits that would fit pollination by long distant foragers such as bees, birds or flies. We studied the pollination biology of Roscoea alpina, observed potential floral visitors and determined their foraging behaviour, visitation frequency and pollination efficiency, to seek evide...