Publications

molecular adaptation of a leaf-eating bird: stomach lysozyme of the hoatzin.	this report describes a lysozyme expressed at high levels in the stomach of the hoatzin, the only known foregut-fermenting bird. evolutionary comparison places it among the calcium-binding lysozymes rather than among the conventional types. conventional lysozymes were recruited as digestive enzymes twice in the evolution of mammalian foregut fermenters, and these independently recruited lysozymes share convergent structural changes attributed to selective pressures in the stomach. biochemical co ...	1994	7815930
why one-kilobase sequences from mitochondrial dna fail to solve the hoatzin phylogenetic enigma.	to address the suitability of mitochondrial dna sequence data for higher avian systematics, cytochrome b sequences for nine species of cuculiformes and galliformes were gathered and compared to those of the hoatzin, a specialized bird whose phylogenetic affinities have long puzzled ornithologists. additional avian cytochrome b sequences from genbank also were incorporated into the comparisons. various phenetic and parsimony analyses applied to the molecular data coded in four formats (nucleotide ...	1994	8075835
phylogenetic relationships of the hoatzin, an enigmatic south american bird.	the hoatzin (opisthocomus hoazin) lives in the humid lowlands of northern and central south america, often in riparian habitats. it is a slender bird approximately 65 cm in length, brownish with lighter streaks and buffy tips to the long tail feathers. the small head has a ragged, bristly crest of reddish-brown feathers, and the bare skin of the face is bright blue. it resembles a chachalaca (ortalis, cracidae) in size and shape, but its plumage and markings are similar to those of the smaller g ...	1995	8524824
molecular genetics and evolution of stomach and nonstomach lysozymes in the hoatzin.	multiple genes of the hoatzin encoding stomach lysozyme c and closely related members of this calcium-binding lysozyme c group were cloned from a genomic dna library and sequenced. there are a minimum of five genes represented among these sequences that encode two distinct groups of protein sequences. one group of three genes corresponds to the stomach lysozyme amino acid sequences, and the remaining genes encode predicted proteins that are more basic in character and share several sequence iden ...	1996	8662020
phylogenetic relationships of the enigmatic hoatzin (opisthocomus hoazin) resolved using mitochondrial and nuclear gene sequences	the hoatzin (opisthocomus hoazin) is a bizarre, long-tailed, crested bird that inhabits the riparian lowlands of south america. among its peculiar attributes are (1) microbial foregut fermentation to convert plant cellulose in consumed foliage into simple sugars, (2) a highly modified skeleton to accommodate its large crop, and (3) in the young of this species, wing claws at the wrist joint which are used to climb among the branches of the nest tree. consequently, the taxonomic position of this ...	1999	10486983
a phylogenetic study of the malagasy couas with insights into cuckoo relationships.	the avian family cuculidae (cuckoos) is a diverse group of birds that vary considerably in behaviors of interest to behavioral ecologists, e.g., obligate brood parasitism and cooperative breeding. the taxonomy of this group has historically been relatively stable but has not been extensively evaluated using molecular methods. the goal of this study was to evaluate phylogenetic relationships within the ecologically diverse genus coua and the placement of coua among major cuckoo lineages. we seque ...	2000	10712848
[adaptations of the hoatzin (opisthocomus hoazin) to leaf-eating. morphological characteristics and functional features of its bill and hyoid apparatus].	the hoatzin remains one of the most enigmatic birds. a morphofunctional analysis of its bill and hyoid apparatus throws new light on its feeding adaptation as well as on its systematic relationships. bony and muscular skull, rhamphotheca, palate, and hyoid apparatus were described in details. though keeping into the general organisation pattern found among neognathae (except galliformes), bill and hyoid apparatus of the hoatzin displays a series of species-specific features, some unique among bi ...	2003	12741184
more taxa, more characters: the hoatzin problem is still unresolved.	the apparently rapid and ancient diversification of many avian orders complicates the resolution of their relationships using molecular data. recent studies based on complete mitochondrial dna (mtdna) sequences or shorter lengths of nuclear sequence have helped corroborate the basic structure of the avian tree (e.g., a basal split between paleognathae and neognathae) but have made relatively little progress in resolving relationships among the many orders within neoaves. we explored the potentia ...	2003	12777516
skull and mandible formation in the cuckoo (aves, cuculidae): contributions to the nomenclature in avian osteology and systematics.	the study of the contributions of different bones to the formation of the skeleton in birds is necessary: (1) to establish homologies in comparative anatomy; (2) to delimit each bone structure correctly, mainly in relation to the skull and mandible where the bones are fused to each other in adults; and (3) to standardize nomenclature in avian osteology. in this paper at least one young specimen belonging to each sub-family of cuculidae was examined in order to identify each bone in terms of boun ...	2010	16982472
a fourth mallophagan species from the hoatzin.		1915	17730887
foregut fermentation in the hoatzin, a neotropical leaf-eating bird.	the only known case of an avian digestive system with active foregut fermentation is reported for the hoatzin (opisthocomus hoazin), one of the world's few obligate folivorous (leaf-eating) birds. hoatzins are one of the smallest endotherms with this form of digestion. foregut fermentation in a flying bird may be explained by increased digestive efficiency by selection of highly fermentable and extremely patchy resources, coupled with microbial nutritional products and secondary compound detoxif ...	1989	17747887
bacterial community in the crop of the hoatzin, a neotropical folivorous flying bird.	the hoatzin is unique among known avian species because of the fermentative function of its enlarged crop. a small-bodied flying foregut fermenter is a paradox, and this bird provides an interesting model to examine how diet selection and the gut microbiota contribute to maximizing digestive efficiency. therefore, we characterized the bacterial population in the crop of six adult hoatzins captured from the wild. a total of 1,235 16s rrna gene sequences were grouped into 580 phylotypes (67% of th ...	2008	18689523
higher-order phylogeny of modern birds (theropoda, aves: neornithes) based on comparative anatomy. ii. analysis and discussion.	in recent years, avian systematics has been characterized by a diminished reliance on morphological cladistics of modern taxa, intensive palaeornithogical research stimulated by new discoveries and an inundation by analyses based on dna sequences. unfortunately, in contrast to significant insights into basal origins, the broad picture of neornithine phylogeny remains largely unresolved. morphological studies have emphasized characters of use in palaeontological contexts. molecular studies, follo ...	2007	18784798
rumen-like methanogens identified from the crop of the folivorous south american bird, the hoatzin (opisthocomus hoazin).	the hoatzin is the only known avian species with foregut fermentation. it is a primarily folivorous feeder and has a distended crop and lower/distal esophagus, which has evolved for the microbial fermentation of ingested feed. crop samples collected from 10 individual animals from the apure river area, apure state, venezuela were examined for the presence and density of methanogens using 16s rrna gene clone libraries and real-time pcr prepared from pooled and individual pcr products. a total of ...	2009	19387486
developmental microbial ecology of the crop of the folivorous hoatzin.	the hoatzin (opisthocomus hoazin) is a south american strict folivorous bird, with a crop microbial ecosystem that ferments dietary plants. chicks progressively become independent from the adult-fed regurgitated crop liquids, and we hypothesized that the crop bacterial ecosystem develops through ecological succession mechanisms, as they grow into adults. the aim of this work was to compare the crop bacterial community in hoatzins from three age groups: newly hatched chicks, juveniles and adults ...	2010	20130656
Comparative analyses of foregut and hindgut bacterial communities in hoatzins and cows.	Foregut fermentation occurs in mammalian ruminants and in one bird, the South American folivorous hoatzin. This bird has an enlarged crop with a function analogous to the rumen, where foregut microbes degrade the otherwise indigestible plant matter, providing energy to the host from foregut fermentation, in addition to the fermentation that occurs in their hindguts (cecum/colon). As foregut fermentation represents an evolutionary convergence between hoatzins and ruminants, our aim was to compare ...	2011	21938024
out of africa: fossils shed light on the origin of the hoatzin, an iconic neotropic bird.	we describe the earliest fossils of the enigmatic avian taxon opisthocomiformes (hoatzins) from the oligo-miocene (22-24 mya) of brazil. the bones, a humerus, scapula and coracoid, closely resemble those of the extant hoatzin, opisthocomus hoazin. the very similar osteology of the pectoral girdle in the new brazilian fossil compared to the extant o. hoazin, in which it reflects peculiar feeding adaptations, may indicate that hoatzins had already evolved their highly specialized feeding behavior ...	2011	21964974
differences in crop bacterial community structure between hoatzins from different geographical locations.	the hoatzin is the only known folivorous bird with foregut fermentation, and is distributed in venezuela in rivers of the central savannas to the eastern orinoco river. differences in diet are expected to affect the digestive microbiota and we hypothesized that hoatzins from different habitats might have a different crop microbiota. we thus characterized the microbiota of six birds from the cojedes and orinoco rivers using the g2 phylochip and, in parallel, we compared plant availability and for ...	2012	22313738
retention of solutes and different-sized particles in the digestive tract of the ostrich (struthio camelus massaicus), and a comparison with mammals and reptiles.	ostriches (struthio camelus) achieve digesta retention times, digesta particle size reduction and digestibilities equal to similar-sized herbivorous mammals, in contrast to some other avian herbivores. the sequence of digestive processes in their gastrointestinal tract, however, is still unexplored. using two groups of four ostriches (mean body mass 75.1 ± 17.3 kg) kept on fresh alfalfa, we tested the effect of two intake levels (17 and 42 g dry matter kg(-0.75)d(-1)) on the mean retention time ...	2012	22609929
earliest and first northern hemispheric hoatzin fossils substantiate old world origin of a "neotropic endemic".	the recent identification of hoatzins (opisthocomiformes) in the miocene of africa showed part of the evolution of these birds, which are now only found in south america, to have taken place outside the neotropic region. here, we describe a new fossil species from the late eocene of france, which constitutes the earliest fossil record of hoatzins and the first one from the northern hemisphere. protoazin parisiensis gen. et sp. nov. is more closely related to south american opisthocomiformes than ...	2014	24441712
a comprehensive phylogeny of birds (aves) using targeted next-generation dna sequencing.	although reconstruction of the phylogeny of living birds has progressed tremendously in the last decade, the evolutionary history of neoaves--a clade that encompasses nearly all living bird species--remains the greatest unresolved challenge in dinosaur systematics. here we investigate avian phylogeny with an unprecedented scale of data: >390,000 bases of genomic sequence data from each of 198 species of living birds, representing all major avian lineages, and two crocodilian outgroups. sequence ...	2015	26444237
the feather mites of the hoatzin opisthocomus hoazin (müller) (aves: opisthocomiformes), with the description of two new genera and six new species (acari: analgoidea, pterolichoidea).	six new species and two new genera of feather mites are described from the hoatzin opisthocomus hoazin (müller) (opisthocomiformes: opisthocomidae) in brazil: gymnolichus lacrimosus sp. n., g. latihumeralis sp. n. (xolalgidae), temnalges hoazin sp. n., t. atelodiscus sp. n. (psoroptoididae), ciganalichus boasfilhoi gen. n., sp. n., and hoazinacarus anisosetus gen. n., sp. n. (pterolichidae). illustrations of two previously known species, opisthocomacarus umbellifer (trouessart, 1899) and stakyon ...	2015	26624451
resource availability and diet in harpy eagle breeding territories on the xingu river, brazilian amazon.	in the tapajos-xingu interfluve, one of the largest birds of prey, the harpy eagle, is under intense anthropogenic pressure due to historical and recent reductions in forest cover. we studied prey availability and use by harpy eagle on six breeding territories on the low- and mid-xingu river, between 2013 and 2015. we evaluated food resource availability using the environmental-surveys database from two methods: terrestrial surveys (rapeld method) and fauna rescue/flushing before vegetation supp ...	2015	26691092
aviisotricha hoazini n. gen., n. sp., the morphology and molecular phylogeny of an anaerobic ciliate from the crop of the hoatzin (opisthocomus hoazin), the cow among the birds.	the hoatzin is the only known avian species that has evolved a foregut fermentation system similar to that of ruminant animals. due to the closeness of the bird's fermentation chamber, the crop, to the bird's beak it exudes an unpleasant odour; therefore, the hoatzin is called the "cow among the birds". in addition to eubacteria and archaea, responsible for digestion of the vegetation they consume, the bird's crop contains a holotrich ciliate, described here for the first time in detail. cytolog ...	2017	28554152
morphological corollaries and ecological implications of flightlessness in the kakapo (psittaciformes: strigops habroptilus).	the morphological corollaries of flightlessness of the kakapo (strigops habroptilus) have been studied using skin specimens, skeletons, and pectoral dissection of an anatomical specimen. these have been compared with the closely related, flighted kea (nestor notabilis), and secondarily with other psittaciformes and the convergent hoatzin (cuculiformes: opisthocomus hoazin). s. habroptilus is the most massive and sexually dimorphic psittaciform in the world, and has the smallest relative wing siz ...	1992	29865598
the karyotype of the hoatzin (opisthocomus hoazin) - a phylogenetic enigma of the neornithes.	the hoatzin (opisthocomus hoazin müller, 1776) is a folivorous bird, endemic to the amazonian region. it presents some unique characteristics, including wing claws and foregut fermentation, which make its phylogenetic relationship to other birds difficult to determine. there have been various attempts to place it among the galliformes, gruiformes, musophagiformes, cuculiformes, and charadriiformes, but phylogenetic analyses always show low supporting values. nowadays, the hoatzin is included in ...	2018	30472715
blood parasites infecting the hoatzin (opisthocomus hoazin), a unique neotropical folivorous bird.	the hoatzin (opisthocomus hoazin) is the only extant member of the order opisthocomiformes. this unique south american bird lives in the riparian lowland vegetation characteristic of the amazon and orinoco basins. hoatzins nest in communal social units close to water bodies; they are strictly folivores being the only bird with pregastric fermentation in the crop. because of the complex logistics involved in capturing this bird, there is a knowledge gap on its parasites. this study documents two ...	2019	30740273
hoatzin nestling locomotion: acquisition of quadrupedal limb coordination in birds.	the evolution of flight in birds involves (i) decoupling of the primitive mode of quadrupedal locomotor coordination, with a new synchronized flapping motion of the wings while conserving alternating leg movements, and (ii) reduction of wing digits and loss of functional claws. our observations show that hoatzin nestlings move with alternated walking coordination of the four limbs using the mobile claws on their wings to anchor themselves to the substrate. when swimming, hoatzin nestlings use a ...	2019	31131317
the c-type lysozyme from the upper gastrointestinal tract of opisthocomus hoatzin, the stinkbird.	muramidases/lysozymes are important bio-molecules, which cleave the glycan backbone in the peptidoglycan polymer found in bacterial cell walls. the glycoside hydrolase (gh) family 22 c-type lysozyme, from the folivorous bird opisthocomus hoazin (stinkbird), was expressed in aspergillus oryzae, and a set of variants was produced. all variants were enzymatically active, including those designed to probe key differences between the hoatzin enzyme and hen egg white lysozyme. four variants showed imp ...	2019	31698762
discovery of a vertebrate-specific factor that processes flagellar glycolytic enolase during motile ciliogenesis.	motile cilia and flagella require atp for their formation and function. although glycolytic enzymes are components of flagellar proteomes, how they translocate to flagella is unknown. here we show that the expression pattern of the functionally nonannotated gene 4833427g06rik (c11orf88), which is found only in vertebrates and is designated here as hoatzin (hoatz), suggests a functional association of its product with motile cilia and flagella. hoatz knockout (ko) mice developed hydrocephalus and ...	2020	32248064
an unbiased molecular approach using 3'utrs resolves the avian family-level tree of life.	presumably, due to a rapid early diversification, major parts of the higher-level phylogeny of birds are still resolved controversially in different analyses or are considered unresolvable. to address this problem, we produced an avian tree of life, which includes molecular sequences of one or several species of ∼ 90% of the currently recognized family-level taxa (429 species, 379 genera) including all 106 for the non-passerines and 115 for the passerines (passeriformes). the unconstrained analy ...	2020	32781465