Publications

TitleAbstractYear
Filter
PMID
Filter
darwin's finches treat their feathers with a natural repellent.darwin's finches are highly innovative. recently we recorded for the first time a behavioural innovation in darwin's finches outside the foraging context: individuals of four species rubbed leaves of the endemic tree psidium galapageium on their feathers. we hypothesised that this behaviour serves to repel ectoparasites and tested the repellency of p. galapageium leaf extracts against parasites that negatively affect the fitness of darwin's finches, namely mosquitoes and the invasive hematophago ...201627721475
interactions between the avian parasite, philornis downsi (diptera: muscidae) and the galapagos flycatcher, myiarchus magnirostris gould (passeriformes: tyrannidae).an incidental observation of the fly philornis downsi parasitizing a galapagos flycatcher (myiarchus magnirostris) nest has revealed new insights into the searching behavior and biology of this invasive fly parasite and its interactions with endemic landbirds in the galapagos islands. observations suggest that p. downsi relies on olfactory cues, or olfactory cues combined with the activity of adult birds, to locate nests and that flies continue to visit nests when chicks are >3 d old. at least 2 ...201526267462
galápagos mockingbirds tolerate introduced parasites that affect darwin's finches.introduced parasites threaten native host species that lack effective defenses. such parasites increase the risk of extinction, particularly in small host populations like those on islands. if some host species are tolerant to introduced parasites, this could amplify the risk of the parasite to vulnerable host species. recently, the introduced parasitic nest fly philornis downsi has been implicated in the decline of darwin's finch populations in the galápagos islands. in some years, 100% of finc ...201628792593
ecoimmunity in darwin's finches: invasive parasites trigger acquired immunity in the medium ground finch (geospiza fortis).invasive parasites are a major threat to island populations of animals. darwin's finches of the galápagos islands are under attack by introduced pox virus (poxvirus avium) and nest flies (philornis downsi). we developed assays for parasite-specific antibody responses in darwin's finches (geospiza fortis), to test for relationships between adaptive immune responses to novel parasites and spatial-temporal variation in the occurrence of parasite pressure among g. fortis populations.201020066052
how to save the rarest darwin's finch from extinction: the mangrove finch on isabela island.habitat destruction and predation by invasive alien species has led to the disappearance of several island populations of darwin's finches but to date none of the 13 recognized species have gone extinct. however, driven by rapid economic growth in the galápagos, the effects of introduced species have accelerated and severely threatened these iconic birds. the critically endangered mangrove finch (camarhynchus heliobates) is now confined to three small mangroves on isabela island. during 2006-200 ...201020194165
identification and optimization of microbial attractants for philornis downsi, an invasive fly parasitic on galapagos birds.we investigated the role of olfactory cues from actively fermenting yeast (saccharomyces cerevisiae) in attraction of adult philornis downsi and identified two synergistically attractive yeast volatiles. larvae of this invasive fly parasitize the hatchlings of passerines and threaten the galapagos avifauna. gas chromatography coupled with electroantennographic detection (gc-ead), coupled gas chromatography-mass spectrometry (gc-ms), and field trapping experiments were used to identify volatile c ...201627744622
genetic variation in the invasive avian parasite, philornis downsi (diptera, muscidae) on the galápagos archipelago.understanding the dispersal and genetic structure of invasive insects across islands is important for designing management plans that are appropriate at spatial and temporal scales. for invasive parasites, population dynamics are largely determined by the distribution and density of their host species. the introduced parasitic fly, philornis downsi, parasitises nestlings of endemic birds on all major islands of the galápagos archipelago. the fly's high mortality and fitness impacts are of conser ...200818671861
isolation, characterization and multiplex polymerase chain reaction of novel microsatellite loci for the avian parasite philornis downsi (diptera: muscidae).an enrichment technique was used to isolate 11 di-, tri-, and tetra microsatellites for the parasitic fly philornis downsi (diptera: muscidae). these loci were polymerase chain reaction amplified in singleplexes or two-plexes for p. downsi. the loci showed low to moderate polymorphism, exhibited between three and four alleles, and observed heterozygosity ranged from 0.05 to 0.86. these new markers will be useful for population-level and paternity analyses and will provide valuable information ab ...200821585739
the life-cycle of philornis downsi (diptera: muscidae) parasitizing darwin's finches and its impacts on nestling survival.the fly, philornis downsi dodge & aitken, was first collected in 1964 on the galápagos islands and is now widespread across the archipelago. virtually nothing is known about the behaviour and ecology of the fly as well as for the genus in general. here, we describe all larval instars for the first time, and discuss infection intensity and impacts of parasitism on nestling survival of darwin's finches. adult p. downsi are non-parasitic free-living flies, whereas the larvae are obligate blood-feed ...200616899139
alien invasion: biology of philornis flies highlighting philornis downsi, an introduced parasite of galápagos birds.the muscid genus philornis comprises approximately 50 described species of flies, nearly all of which are obligate parasites of nestling birds. philornis species are native to the neotropics and widely distributed from florida to argentina. most research on this group has focused on p. downsi, which was introduced to the galápagos islands in the late twentieth century. although philornis parasitism kills nestlings in several native host species, nowhere do the effects seem more severe than in p. ...201829058976
invasive parasites, habitat change and heavy rainfall reduce breeding success in darwin's finches.invasive alien parasites and pathogens are a growing threat to biodiversity worldwide, which can contribute to the extinction of endemic species. on the galápagos islands, the invasive parasitic fly philornis downsi poses a major threat to the endemic avifauna. here, we investigated the influence of this parasite on the breeding success of two darwin's finch species, the warbler finch (certhidea olivacea) and the sympatric small tree finch (camarhynchus parvulus), on santa cruz island in 2010 an ...201425248092
darwin's finches combat introduced nest parasites with fumigated cotton.introduced parasites are a threat to biodiversity when naïve hosts lack effective defenses against such parasites [1]. several parasites have recently colonized the galápagos islands, threatening native bird populations [2]. for example, the introduced parasitic nest fly philornis downsi (diptera: muscidae) has been implicated in the decline of endangered species of darwin's finches, such as the mangrove finch (camarhynchus heliobates) [3]. here, we show that darwin's finches can be encouraged t ...201424801182
first record of the avian ectoparasite philornis downsi dodge & aitken, 1968 (diptera: muscidae) in argentina.species of philornis meinert, 1890 (diptera, muscidae) are neotropical dipterans that include species with parasitic larvae which feed on nestling birds. to date, all philornis species that have been recorded from argentina have parasitic subcutaneous larvae. here, for the first time for argentina, we report the finding of philornis downsi dodge & aitken, 1968, a fly with a nest-dwelling, semi-haematophagous larva. this record, from the humid chaco ecoregion of argentina in the nest of a saffron ...201121898202
rearing larvae of the avian nest parasite, philornis downsi (diptera: muscidae), on chicken blood-based diets.captive rearing of insect pests is necessary to understand their biology and to develop control methods. the avian nest fly, philornis downsi dodge and aitken, is a blood-sucking parasite during its larval stage and a serious threat to endemic birds in the galapagos islands where it is considered invasive. in order to procure large numbers of flies for biological studies, rearing media and diets were trialed for rearing the larval stage of p. downsi under controlled conditions in the absence of ...201627493240
experimental demonstration of the fitness consequences of an introduced parasite of darwin's finches.introduced parasites are a particular threat to small populations of hosts living on islands because extinction can occur before hosts have a chance to evolve effective defenses. an experimental approach in which parasite abundance is manipulated in the field can be the most informative means of assessing a parasite's impact on the host. the parasitic fly philornis downsi, recently introduced to the galápagos islands, feeds on nestling darwin's finches and other land birds. several correlational ...201121589659
experimental demonstration of a parasite-induced immune response in wild birds: darwin's finches and introduced nest flies.ecological immunology aims to explain variation among hosts in the strength and efficacy of immunological defenses. however, a shortcoming has been the failure to link host immune responses to actual parasites under natural conditions. here, we present one of the first experimental demonstrations of a parasite-induced immune response in a wild bird population. the recently introduced ectoparasitic nest fly philornis downsi severely impacts the fitness of darwin's finches and other land birds in ...201324567824
an introduced parasitic fly may lead to local extinction of darwin's finch populations.introduced pathogens and other parasites are often implicated in host population level declines and extinctions. however, such claims are rarely supported by rigorous real-time data. indeed, the threat of introduced parasites often goes unnoticed until after host populations have declined severely. the recent introduction of the parasitic nest fly, philornis downsi, to the galápagos islands provides an opportunity to monitor the current impact of an invasive parasite on endemic land bird populat ...201626980922
galápagos mockingbirds tolerate introduced parasites that affect darwin's finches.introduced parasites threaten native host species that lack effective defenses. such parasites increase the risk of extinction, particularly in small host populations like those on islands. if some host species are tolerant to introduced parasites, this could amplify the risk of the parasite to vulnerable host species. recently, the introduced parasitic nest fly philornis downsi has been implicated in the decline of darwin's finch populations in the galápagos islands. in some years, 100% of finc ...201627220210
host-specific associations affect the microbiome of philornis downsi, an introduced parasite to the galápagos islands.the composition and diversity of bacteria forming the microbiome of parasitic organisms have implications for differential host pathogenicity and host-parasite co-evolutionary interactions. the microbiome of pathogens can therefore have consequences that are relevant for managing disease prevalence and impact on affected hosts. here, we investigate the microbiome of an invasive parasitic fly philornis downsi, recently introduced to the galápagos islands, where it poses extinction threat to darwi ...201728664982
females drive asymmetrical introgression from rare to common species in darwin's tree finches.the consequences of hybridization for biodiversity depend on the specific ecological and evolutionary context in which it occurs. understanding patterns of gene flow among hybridizing species is crucial for determining the evolutionary trajectories of species assemblages. the recently discovered hybridization between two species of darwin's tree finches (camarhynchus parvulus and c. pauper) on floreana island, galápagos, presents an exciting opportunity to investigate the mechanisms causing hybr ...201728833876
experimental test of the effect of introduced hematophagous flies on corticosterone levels of breeding darwin's finches.parasites can negatively affect the evolutionary fitness of their hosts by eliciting physiological stress responses. parasite-induced stress can be monitored by measuring changes in the adrenal steroid hormone corticosterone. we examined the effect of an invasive parasite on the corticosterone concentrations of a common species of darwin's finch, the medium ground finch (geospiza fortis). philornis downsi (diptera: muscidae) is a parasitic nest fly recently introduced to the galapagos islands, w ...201323892015
Displaying items 1 - 21 of 21