| a molecular phylogenetic survey of the nightjars and allies (caprimulgiformes) with special emphasis on the potoos (nyctibiidae). | a 656-pb fragment of the mitochondrial cytochrome b gene was sequenced for six species of central and south american potoos (genus nyctibius, nyctibiidae) as well as for selected representatives of all other caprimulgiform families. sequence divergence among potoos was much higher (11.1-16.2%) than has typically been observed among congeneric species of birds, suggesting that the species of nyctibius are quite old. divergence among families was also quite high (13.7-21.8%), confirming recent dna ... | 1996 | 8899725 |
| isolation of histoplasma capsulatum from an oil bird (steatornis caripensis) cave in venezuela. | | 1960 | 13792225 |
| occurrence of histoplasma capsulatum on the island of trinidad, b. w. i. i. survey of steatornis caripensis (oil bird) habitats. | | 1962 | 13859868 |
| the evolution of stereopsis and the wulst in caprimulgiform birds: a comparative analysis. | owls possess stereopsis (i.e., the ability to perceive depth from retinal disparity cues), but its distribution amongst other birds has remained largely unexplored. here, we present data on species variation in brain and telencephalon size and features of the wulst, the neuroanatomical substrate that subserves stereopsis, in a putative sister-group to owls, the order caprimulgiformes. the caprimulgiforms we examined included nightjars (caprimulgidae), owlet-nightjars (aegothelidae), potoos (nyct ... | 2006 | 16944165 |
| the comparative morphology of the cerebellum in caprimulgiform birds: evolutionary and functional implications. | interspecific variation in the structure of the avian cerebellum is poorly understood. we present the first comparison of cerebellar morphology within the avian order caprimulgiformes. using a range of qualitative descriptions and quantitative measurements of cerebellar morphology we compared caprimulgiform birds with hummingbirds and swifts (apodiformes) and owls (strigiformes), two groups that are putative sister taxa to the caprimulgiformes. our results demonstrate that the owlet-nightjars (a ... | 2006 | 16244465 |
| it's not black or white-on the range of vision and echolocation in echolocating bats. | around 1000 species of bats in the world use echolocation to navigate, orient, and detect insect prey. many of these bats emerge from their roost at dusk and start foraging when there is still light available. it is however unclear in what way and to which extent navigation, or even prey detection in these bats is aided by vision. here we compare the echolocation and visual detection ranges of two such species of bats which rely on different foraging strategies (rhinopoma microphyllum and pipist ... | 2013 | 24065924 |
| retinal morphology and electrophysiology of two caprimulgiformes birds: the cave-living and nocturnal oilbird (steatornis caripensis), and the crepuscularly and nocturnally foraging common pauraque (nyctidromus albicollis). | oilbirds (steatornis caripensis) breed in the total darkness of caves and forage at night on fruits. common pauraques (nyctidromus albicollis) are crepuscular and nocturnal foragers on flying insects. we examined if their retinal structure and function can be correlated with their types and periods of activity. electroretinograms (ergs) were obtained from anesthetized birds in photopic and scotopic conditions to a wide range of light intensities, following which the retinas were processed for hi ... | 2004 | 15051964 |
| oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions. | oilbirds are active at night, foraging for fruits using keen olfaction and extremely light-sensitive eyes, and echolocate as they leave and return to their cavernous roosts. we recorded the echolocation behaviour of wild oilbirds using a multi-microphone array as they entered and exited their roosts under different natural light conditions. during echolocation, the birds produced click bursts (cbs) lasting less than 10 ms and consisting of a variable number (2-8) of clicks at 2-3 ms intervals. t ... | 2017 | 28573036 |
| echolocation in oilbirds and swiftlets. | the discovery of ultrasonic bat echolocation prompted a wide search for other animal biosonar systems, which yielded, among few others, two avian groups. one, the south american oilbird (steatornis caripensis: caprimulgiformes), is nocturnal and eats fruit. the other is a selection of diurnal, insect-eating swiftlets (species in the genera aerodramus and collocalia: apodidae) from across the indo-pacific. bird echolocation is restricted to lower frequencies audible to humans, implying a system o ... | 2013 | 23755019 |
| podargiform affinities of the enigmatic fluvioviridavis platyrhamphus and the early diversification of strisores ("caprimulgiformes" + apodiformes). | the early eocene green river formation avifauna preserves exceptional exemplars of the earliest unambiguous stem representatives of many extant avian clades. we identify the basal-most member of podargiformes (extant and fossil stem lineage frogmouths) based on a new specimen of fluvioviridavis platyrhamphus, a unique neoavian bird from the fossil butte member of the green river formation of wyoming. extant frogmouths (podargidae) comprise approximately 13 nocturnal species with an exclusively a ... | 2011 | 22140427 |
| the secret life of oilbirds: new insights into the movement ecology of a unique avian frugivore. | steatornis caripensis (the oilbird) is a very unusual bird. it supposedly never sees daylight, roosting in huge aggregations in caves during the day and bringing back fruit to the cave at night. as a consequence a large number of the seeds from the fruit they feed upon germinate in the cave and spoil. | 2009 | 20016844 |
| do swiftlets have an ear for echolocation? the functional morphology of swiftlets' middle ears. | the oilbird and many swiftlet species are unique among birds for their ability to echolocate. echolocaters may benefit from improved hearing sensitivity. therefore, morphological adaptations to echolocation might be present in echolocating birds' middle ears. we studied the functional morphology of the tympano-ossicular chain of seven specimens of four echolocating swiftlet species and one specimen each of five non-echolocating species. three dimensional (3d) reconstructions were made from micro ... | 2007 | 17229537 |
| the eyes of oilbirds (steatornis caripensis): pushing at the limits of sensitivity. | an extreme example of a low light-level lifestyle among flying birds is provided by the oilbird, steatornis caripensis (steatornithidae, caprimulgiformes). oilbirds breed and roost in caves, often at sufficient depth that no daylight can penetrate, and forage for fruits at night. using standard microscopy techniques we investigated the retinal structure of oilbird eyes and used an ophthalmoscopic reflex technique to determine the parameters of these birds' visual fields. the retina is dominated ... | 2004 | 14740100 |
| variable asymmetry and resonance in the avian vocal tract: a structural basis for individually distinct vocalizations. | the social vocalizations of the oilbird (steatornis caripensis) frequently have their acoustic energy concentrated into 3 prominent formants which appear to arise from the filter properties of their asymmetrical vocal tract with its bronchial syrinx. the frequency of the second and third formants approximate the predicted fundamental resonances of the unequal left and right cranial portions of each primary bronchus, respectively. reversibly plugging either bronchus eliminates the corresponding f ... | 1994 | 7965918 |
| the oilbird: hearing and echolocation. | oilbirds can navigate in total darkness by echolocation. the sound energy in their sonar cries is unevenly distributed over the range from about 1 to 15 kilohertz, with a dominant frequency range of 1.5 to 2.5 kilohertz. this corresponds to the most sensitive range of their hearing as determined by neurophysiological methods. behavioral tests in their home cave indicate that the smallest object avoided by this is a disk 20 centimeters in diameter. | 1979 | 441731 |
| evolutionary and ecological correlates of quiet flight in nightbirds, hawks, falcons, and owls. | two hypotheses have been proposed for the evolution of structures that reduce flight sounds in birds. according to the stealth hypothesis, flying quietly reduces the ability of other animals (e.g. prey) to detect the animal's approach from its flight sounds. this hypothesis predicts that animals hunting prey with acute hearing evolve silencing features. the self-masking hypothesis posits that reduced flight sounds permit the animal itself to hear better (such as the sounds of its prey, or its ow ... | 2020 | 32426839 |
| oilbirds. | a quick guide to oilbirds: nocturnal birds found only in neotropical rainforests that, rather like many bat species, live in caves where they use echolocation for orientation. | 2017 | 29112862 |