| interspecific signalling between mutualists: food-thieving drongos use a cooperative sentinel call to manipulate foraging partners. | interspecific communication is common in nature, particularly between mutualists. however, whether signals evolved for communication with other species, or are in fact conspecific signals eavesdropped upon by partners, is often unclear. fork-tailed drongos (dicrurus adsimilis) associate with mixed-species groups and often produce true alarms at predators, whereupon associating species flee to cover, but also false alarms to steal associating species' food (kleptoparasitism). despite such decepti ... | 2014 | 25080343 |
| deception by flexible alarm mimicry in an african bird. | deception is common in nature, but victims of deception discriminate against and ultimately ignore deceptive signals when they are produced too frequently. flexible variation of signals could allow evasion of such constraints. fork-tailed drongos (dicrurus adsimilis) use false alarm calls to scare other species away from food that they then steal. we show that drongos mimic the alarms of targeted species. further, target species reduce their response to false alarm calls when they are repeated. ... | 2014 | 24786078 |
| the ecological economics of kleptoparasitism: pay-offs from self-foraging versus kleptoparasitism. | animals commonly steal food from other species, termed interspecific kleptoparasitism, but why animals engage in kleptoparasitism compared with alternate foraging tactics, and under what circumstances they do so, is not fully understood. determining what specific benefits animals gain from kleptoparasitism could provide valuable insight into its evolution. here, we investigate the benefits of kleptoparasitism for a population of individually recognizable and free-living fork-tailed drongos (dicr ... | 2013 | 22943364 |
| singing for your supper: sentinel calling by kleptoparasites can mitigate the cost to victims. | parasitism generally imposes costs on victims, yet many victims appear to tolerate their parasites. we suggest that in some cases this may be because parasites provide victims with mitigating benefits, paradoxically giving rise to selection for advertisement rather than concealment by parasites. we investigate this possibility using the interaction between an avian kleptoparasite, the fork-tailed drongo (dicrurus adsimilis), and one of its victims, the pied babbler (turdoides bicolor). combining ... | 2011 | 21361918 |
| fork-tailed drongos use deceptive mimicked alarm calls to steal food. | despite the prevalence of vocal mimicry in animals, few functions for this behaviour have been shown. i propose a novel hypothesis that false mimicked alarm calls could be used deceptively to scare other species and steal their food. studies have previously suggested that animals use their own species-specific alarm calls to steal food. however none have shown conclusively that these false alarms are deceptive, or that mimicked alarm calls are used in this manner. here, i show that wild fork-tai ... | 2011 | 21047861 |
| the presence of an avian co-forager reduces vigilance in a cooperative mammal. | many animals must trade-off anti-predator vigilance with other behaviours. some species facilitate predator detection by joining mixed-species foraging parties and 'eavesdropping' on the predator warnings given by other taxa. such use of heterospecific warnings presumably reduces the likelihood of predation, but it is unclear whether it also provides wider benefits, by allowing individuals to reduce their own vigilance. we examine whether the presence of an avian co-forager, the fork-tailed dron ... | 2010 | 20129949 |
| interspecific audience effects on the alarm-calling behaviour of a kleptoparasitic bird. | audience effects are increasingly recognized as an important aspect of intraspecific communication. yet despite the common occurrence of interspecific interactions and considerable evidence that individuals respond to the calls of heterospecifics, empirical evidence for interspecific audience effects on signalling behaviour is lacking. here we present evidence of an interspecific audience effect on the alarm-calling behaviour of the kleptoparasitic fork-tailed drongo (dicrurus adsimilis). when f ... | 2007 | 17698446 |
| immunocytochemistry of the pars tuberalis of the pituitary gland in some indian wild birds: a comparative study. | immunohistochemistry has been applied to the cells of the pars tuberalis (pt) of the pituitary gland of three species of indian wild birds (halcyon smyrnensis perpulchra, lonchura striata striata, dicrurus adsimilis macrocercus). as in the pars distalis (pd), five types of immunoreactive cells (gonadotropic, gth; thyrotropic, tsh; lactotropic/prolactin, prl; growth hormone/somatotropic, sth; and cortico-melanotropic, acth/msh cells) are present in the pt of these birds. in addition to the gth ce ... | 1997 | 9378265 |
| birdcall lures improve passerine mist-net captures at a sub-tropical african savanna. | field research techniques are constantly evolving to meet the needs of the scientific community. there is a growing need for field biology studies to shift towards increasing efficiency and quality of results while simultaneously decreasing cost in both the researcher's time and resources. i tested the efficacy of using multiple recorded birdcall lures (n = 172 species) to improve mist-net captures at a subtropical african savanna setting. capture success was compared between passive and birdcal ... | 2018 | 29928048 |