Many birds display plumage coloration and patterns that act as visual aposematic mimetic signals for predators. Avian aposematism can also be communicated via chemical cues, where so-called non-host odours (NHO) emitted from the plumage, uropygial (preen) gland or other sources denote status of dangerous unprofitable hosts ectoparasitic haematophagous arthropods. NHO are in natural concentratio...

Prolactin plays an important role in mediating parental care in birds, but little is known about changes in prolactin levels when animals disrupt their reproductive behaviour during emergency life-history stages. We investigated the variation of prolactin levels with breeding stage, sex, body condition and as a response to a standardized acute stressor in a small short-lived bird, the Eurasian ...

The uropygial gland (preen gland) is a holocrine secretory gland situated at the base of the tail in birds which produces a hydrophobic fatty secretion. In certain birds, such as the hoopoe, Upupa epops, the composition of this secretion is influenced by both seasonal and sexual factors, becoming darker and more malodorous in females and in their nestlings during the nesting phase. The secretio...

Global warming is occurring at an alarming rate and predictions are that air temperature (T a) will continue to increase during this century. Increases in T a as a result of unabated production of greenhouse gases in our atmosphere pose a threat to the distribution and abundance of wildlife populations worldwide. Although all the animals worldwide will likely be affected by global warming, diur...

is no unambiguous evidence that plumicolous feather mites chew holes in feathers; such damage is usually caused by feather lice. Also, it has been reported that feather mites of the great-spotted woodpecker (Dryobates major) and the hoopoe (Upupa epops) avoid white spots on the feathers and instead aggregate on melanized areas 5. Thus, as we stressed in our review 3 , extrapolating from lice to...

Bird skin has a number of specific properties. The uropygial gland is a significant skin gland in many species. The secretion of this gland is particularly necessary for maintaining physical characteristics, including feather waterproofing. In some bird species this gland secretion has a repellent effect against potential mammalian predators; in other species it affects the final colour of feat...

A vian interspecific brood parasitism occurs when a female bird uses a different host species to incubate and rear her offspring. Studies of this parasitic behavior have provided some of nature’s most compelling examples of coevolutionary interactions (1). Avian brood parasites exhibit wide variation in host specificity, ranging from one or a few hosts to hundreds, and there is a concomitant de...

Ever since Antiphanes brought on the stage a character, perhaps Comedy herself, complaining that comedy was more difficult to compose than tragedy (fr. 189.17-23 K-A), it has become something of a truism to say that the poets of Old Comedy had at their disposal much richer and less generically restricted literary possibilities than their colleagues working in tragedy. Comments Postprint version...