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A feather with possible ectoparasite eggs from the Crato Formation (Lower Cretaceous, Aptian) of Brazil
Abstract
An almost symmetrical, isolated feather from the Crato Formation is associated with numerous spherical, hollow structures approximately 75 microns diameter which are interpreted as the eggs of an avian ectoparasite, probably a mite. The feather shape resembles the caudal feathers of modern birds and Archaeopteryx, but it appears to have only simple barbules. This specimen may represent the oldest occurrence of ectoparasitism on feathered maniraptorans.
... From the three specimens studied, only GP/2E-7853 shows a coloration (reddish/orange) that is typical of the iron oxides-hydroxides, possibly limonite. This type of preservation was also observed in others feathers from the same provenance (Maisey, 1991;Martins-Neto & Kellner, 1988;Martill & Frey, 1995;Martill & Davis, 2001). The remaining specimens, may be preserved as incarbonization, once it is one of the most common type of preservation of organic molecules, as it presents the characteristic dark black hue (Tegelaar et al., 1989;Davis & Briggs, 1990;1995;Kellner, 2002;Briggs, 2003). ...
... The main hypothesis that explains the presence of the isolated feathers in the fossil record, especially in the Santana Formation, assumes that these elements may have been blown into the paleolake by events of strong winds. Once they have reached the waters of the lake, these feathers may have sunk quickly, reaching the bottom in seconds to few minutes, where they were rapidly buried (Martill & Davis, 2001). Despite the fact that this hypothesis satisfy this question, others mechanisms (and educated guesses) may also be praised. ...
... Despite the occasional events of great sediment deposition, the preservation of the carcass of these animals (often huge), required more time to be completely buried, and so, preserved. This slow process opposes to the rapid burial of feathers as suggested elsewhere (Martill & Davis, 2001), explaining their absence alongside sauropods and great ornithischians bones. ...
Feathers are the most complex and diversified integuments in vertebrates. Their complexity are provided by the different forms and functions, and they occur both in non-avian and avian-dinosaurs. Despite their rareness, feathers are found throughout the world, and the Santana Formation (comprised by Crato and Romualdo formations) of the Araripe Basin is responsible for the majority of these records in Brazil. Most occurrences is consisted by isolated feathers, where downy-feathers is the recurrent morphotype, two coelurosaurs and one enantiornithe bird. The sedimentary deposition of this unit is consisted by a lacustrine (Crato Fm) and lagoonal (Romualdo Fm) environments, where reducing conditions prevailed, precluding the activity of bottom dwelling organisms that favored the exquisite preservation. Despite the arid and hot conditions during the Cretaceous, life teemed in the adjacency of both paleolakes, however, feathered non-avian dinosaurs were not found yet in the Crato Member. By the great diversity of life that existed in the paleolake surroundings, is possible to recognize, through the fossil record, that a complex and diversified trophic chain was well established during the time period of sedimentation of this unit. When the remains reached the bottom of the paleolakes, the subsequent isolation from the environment allowed their preservation. In this work, three fossilized feathers, consisted of two downy and one contour feather, extracted from the laminated limestone of the Crato Member of the Santana Formation, were described and identified according to morphological and evolutionary models. We also used the terminology commonly applied to extant organisms. Relying on the fossil record of this unit and the adjacencies formations and basins (by autochthonous condition), taxonomic inferences can be made when the lowest hierarchy level is considered, and hence, is possible to propose the plausible taxa that could bear these elements. Taphonomic and paleoecological aspects, such as the preservation of these structures, and the presence of dinosaurs, were also reviewed, as well as the future perspectives about the study of these elements. Despite the virtual low significance, the pragmatical study of fossilized feathers, can help with the understanding of the evolution and paleobiology of dinosaurs, especially on the South Hemisphere.
... From the three specimens studied, only GP/2E-7853 shows a coloration (reddish/orange) that is typical of the iron oxides-hydroxides, possibly limonite. This type of preservation was also observed in others feathers from the same provenance (Maisey, 1991;Martins-Neto & Kellner, 1988;Martill & Frey, 1995;Martill & Davis, 2001). The remaining specimens, may be preserved as incarbonization, once it is one of the most common type of preservation of organic molecules, as it presents the characteristic dark black hue (Tegelaar et al., 1989;Davis & Briggs, 1990;1995;Kellner, 2002;Briggs, 2003). ...
... The main hypothesis that explains the presence of the isolated feathers in the fossil record, especially in the Santana Formation, assumes that these elements may have been blown into the paleolake by events of strong winds. Once they have reached the waters of the lake, these feathers may have sunk quickly, reaching the bottom in seconds to few minutes, where they were rapidly buried (Martill & Davis, 2001). Despite the fact that this hypothesis satisfy this question, others mechanisms (and educated guesses) may also be praised. ...
... Despite the occasional events of great sediment deposition, the preservation of the carcass of these animals (often huge), required more time to be completely buried, and so, preserved. This slow process opposes to the rapid burial of feathers as suggested elsewhere (Martill & Davis, 2001), explaining their absence alongside sauropods and great ornithischians bones. ...
Feathers are the most complex and diversified integuments in vertebrates. Their complexity are provided by the different forms and functions, and they occur both in non-avian and avian-dinosaurs. Despite their rareness, feathers are found throughout the world, and the Santana Formation (comprised by Crato and Romualdo formations) of the Araripe Basin is responsible for the majority of these records in Brazil. Most occurrences is consisted by isolated feathers, where downy-feathers is the recurrent morphotype, two coelurosaurs and one enantiornithe bird. The sedimentary deposition of this unit is consisted by a lacustrine (Crato Fm) and lagoonal (Romualdo Fm) environments, where reducing conditions prevailed, precluding the activity of bottom dwelling organisms that favored the exquisite preservation. Despite the arid and hot conditions during the Cretaceous, life teemed in the adjacency of both paleolakes, however, feathered non-avian dinosaurs were not found yet in the Crato Member. By the great diversity of life that existed in the paleolake surroundings, is possible to recognize, through the fossil record, that a complex and diversified trophic chain was well established during the time period of sedimentation of this unit. When the remains reached the bottom of the paleolakes, the subsequent isolation from the environment allowed their preservation. In this work, three fossilized feathers, consisted of two downy and one contour feather, extracted from the laminated limestone of the Crato Member of the Santana Formation, were described and identified according to morphological and evolutionary models. We also used the terminology commonly applied to extant organisms. Relying on the fossil record of this unit and the adjacencies formations and basins (by autochthonous condition), taxonomic inferences can be made when the lowest hierarchy level is considered, and hence, is possible to propose the plausible taxa that could bear these elements. Taphonomic and paleoecological aspects, such as the preservation of these structures, and the presence of dinosaurs, were also reviewed, as well as the future perspectives about the study of these elements. Despite the virtual low significance, the pragmatical study of fossilized feathers, can help with the understanding of the evolution and paleobiology of dinosaurs, especially on the South Hemisphere.
... Taphonomy: The color of this specimen (orange/reddish), suggests that the fossil may be preserved as an iron oxide. The matrix light beige color may be the result of slight weathering, calcified filaments and dendritic crystals of sphalerite (Martill & Davis, 2001; Heimhofer et al., 2010). Diagnosis: Despite a fairly generic morphotype, this specimen has typical plumulaceous feather morphology due to the presence of very well delineated rachis and barbs of varying sizes. ...
... From the three specimens studied, only GP/2E-7853 shows coloration (reddish/orange) that is typical of the iron oxides-hydroxides, possibly limonite. This type of preservation was also observed in other feathers from the same provenance (Maisey, 1991; Martins-Neto & Kellner, 1988; Martill & Frey, 1995; Martill & Davis, 2001). The remaining specimens may be preserved as incarbonization, one of the most common type of preservation of organic molecules, with characteristic dark black hue (Tegelaar et al., 1989; Davis & Briggs, 1995; Kellner, 2002; Briggs, 2003). ...
... The main hypothesis that explains the presence of isolated feathers in the fossil record, as is in the Crato, assumes that these elements may have been blown into the paleolake by strong winds events. Once they have reached the lake, these feathers would sink quickly, reaching the bottom in seconds to a few minutes, where they might be rapidly buried (Martill & Davis, 2001). Birds normally lose their feathers during ontogenetic phases or seasonably. ...
Here we describe three fossil feathers from the Early Cretaceous Santana Formation of the Araripe Basin, Brazil. Feathers are the most complex multiform vertebrate integuments; they perform different functions, occurring in both avian and non-avian dinosaurs. Despite their rarity, fossil feathers have been found across the world. Most of the Brazilian feather fossil record comes from the Santana Formation. This formation is composed of two members: Crato (lake) and Romualdo (lagoon); both of which are predominantly reduced deposits, precluding bottom dwelling organisms, resulting in exceptional preservation of the fossils. Despite arid and hot conditions during the Cretaceous, life teemed in the adjacency of this paleolake. Feathered non-avian dinosaurs have not yet been described from the Crato Member, even though there are suggestions of their presence in nearby basins. Our description of the three feathers from the Crato laminated limestone reveals that, despite the small sample size, they can be referred to coelurosaurian theropods. Moreover, based on comparisons with extant feather morphotypes they can be identified as one contour feather and two downy feathers. Despite their rareness and low taxonomic potential, fossilized feathers can offer insights about the paleobiology of its owners and the paleoecology of the Araripe Basin.
... The fine sediments of the Trememb e Formation were laid down in a swampy lake surrounded by a rich vegetation (Duarte & Mardarim-de-Lacerda, 1992;Mandarim-de-Lacerda and Bernardes-de-Oliveira, 1999;Veiga, 2009). The biota is represented by diversified fossils of mammals, reptiles, birds, fishes, arthropods, plants and several types of ichnotaxons (Ferreira, 1974;Fernandes et al., 1987;Chiappe, 1988;Carvalho and Fernandes, 1989;Martins-Neto, 1998;Malabarba, 2000;Bernardes-de-oliveira et al., 2002aBernardes-de-oliveira et al., , 2002bOlson and Alvarenga, 2002;Melo et al., 2007;Veiga, 2009;Ribeiro, 2010;Mayr et al., 2011a;Bergue et al., 2015aBergue et al., , 2015b. While younger in age, the high quality of its fossils is comparable to the Eocene Messel Shale Pit fossils (Franzen, 1985), as soft tissues of different groups of organisms, such as plants and vertebrates, were exquisitely preserved (Prado et al., 2015). ...
... Thus, it is not rare to find fossils in disorganized arrangements or as fragmented remnants. According to the "drift hypothesis" proposed for other deposits (Martill and Davis, 2001), these feathers might have been blown into the paleolake by strong winds, where it then sunk and was rapidly buried. Davis (1994) suggests that isolated feathers (mainly downy feathers), reach the bottom of an aquatic environment in a short period of time, ranging from seconds to a few minutes. ...
Feathers are rare in the fossil record because they have a low fossilization potential. Despite their palaeobiological significance, they also provide important palaeoecological and taphonomic information. Here, we report a new occurrence of three isolated feathers from the shales of the Oligocene Tremembé Formation (Taubaté Basin, SE Brazil). Their possible taxonomic affinities and taphonomic features are also discussed. Analyses identified the specimens as representatives of two pennaceous morphotypes (i.e., a contour and a rectrice feather). Both are preserved as carbonized traces, although, due taphonomic processes, they show different degrees of preservation. Since the Tremembé Formation is responsible for the most diverse record of Cenozoic birds, and because water-adapted birds (e.g., anseriformes and phoenicopteriformes) occur in this unit, it is highly possible that these feathers belonged to these aquatic taxa. Further investigations should concentrate on geochemical and microscopic techniques in order to reveal additional taxonomic and paleoecological features currently unknown in Paleogene birds of Brazil.
... It can therefore be assumed that birds and other feathered dinosaurs have been grooming or preening their plumage ever since feathers originated. Mesozoic arthropods that were possible parasites of feathered theropods are known, and the eggs of possible Mesozoic feather parasites were reported by Martill & Davis (2001) though later suggested to be ostracod eggs (Proctor, 2003). Given that incisiform, projecting anterior teeth are present in numerous Mesozoic birds (Fig. 5), oviraptorosaurs and other coelurosaurs, it is tempting to suggest that dental reduction and evolution in birds and other coelurosaurs was driven (in part) by selection for use of the teeth in preening. ...
Between the Middle Jurassic and Holocene, birds evolved an enormous diversity of behaviours. The distribution and antiquity of these behaviours is difficult to establish given a relatively poor fossil record. Rare crop, stomach and gut contents typically reveal diets consistent with morphology but stem‐members of some lineages (including Cariamae and Coraciiformes) seem to have been different in ecology from their extant relatives. Most of our ideas about the behaviour of fossil birds are based on analogy (with skull form, limb proportions and claw curvature being used to guide hypotheses). However, this has limitations given that some extinct taxa lack extant analogues and that some extant taxa do not behave as predicted by osteology. Reductionist methods have been used to test predation style and running ability in fossil taxa including moa, G astornis and phorusrhacids. Virtually nothing is known of nesting and nest‐building behaviour but colonial nesting is known from the Cretaceous onwards. Rare vegetative nests demonstrate modern nest‐building from the Eocene onwards. Ornamental rectrices indicate that sexually driven display drove some aspects of feather evolution and evidence for loud vocal behaviour and intraspecific combat is known for some taxa. Our knowledge of fossil bird behaviour indicates that ‘modern’ behaviours are at least as old as crown birds. Stem‐members of extant lineages, however, may sometimes or often have differed from extant taxa.
... Many bird tracks have been found in and around the pterosaur tracks at Uhangri (Figs 7d, 8b), from which it can be deduced that birds and pterosaurs either were present simultaneously on the mud flats, or that birds visited the flats very soon after the pterosaurs, sometimes stepping in their tracks. The cooccurrence of skeletal remains of pterosaurs and birds has been reported from a number of localities including the Upper Jurassic Solnhofen Limestone of Bavaria (Wellnhofer, 1983), the Lower Cretaceous Yixian Formation of Liaoning, China (Wang et al. 1998), the Crato Formation of Brazil (Martill, 1993;Martill & Davis, 2001), the Cambridge Greensand of England (Seeley, 1869), the Upper Cretaceous Beleuta Formation of Uzbekistan (Bakhurina & Unwin, 1995) and Niobrara Chalk of western North America. The traces from the Uhangri and North Horn formations (Lockley, 1999) and the Oncala Group (Fuentes Vidarte, 2001) provide the first clear evidence that pterosaurs and birds inhabited, or at least visited the same environments. ...
Numerous footprints of dinosaurs, pterosaurs and birds, together with arthropod tracks, have been discovered in the upper Cretaceous Uhangri Formation which crops out along the south-western coastline of South Korea. This ichnofauna contains the first pterosaur tracks reported from Asia. The digitigrade tridactyl manus impressions exhibit features of a typical pterosaur hand print. The pes impressions, however, show features that are different from pterosaur footprints reported previously: there is no visible trace of impressions of individual digits, and the toes are triangular or rounded in shape distally without distinct claw impressions. As these features clearly distinguish the Uhangri tracks from Pteraichnus and Purbeckopus, we assign them to a new genus, Haenamichnus which accommodates the new ichnospecies, Haenamichnusuhangriensis. The prints are five to six times larger than those of Pteraichnus, and are currently the largest pterosaur ichnites known. They show virtually no trace of the 5th phalange of the pes, indicating that they were made by pterodactyloids; moreover, features of the tracks suggest that they can be attributed to azhdarchids, the commonest pterosaur of the Late Cretaceous. The longest pterosaur trackway yet known from any track site (length 7.3 m) and consisting of 14 pairs of foot impressions, was also found in the Uhangri Formation and suggests that azhdarchids, at least, were competent terrestrial locomotors. The fossil track site at Uhangri represents the first occurrence of the tracks of pterosaurs, dinosaurs and web-footed birds all on the same level. This demonstrates that pterosaurs and birds visited the same habitat, but the large size disparity suggests that they occupied different ecological niches.
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Introduction Remains of possible birds are extremely rare in the Crato Formation and have so far only been reported from the Nova Olinda Member. The first report was of an isolated probable remex (Figure 18.1a) described by Martins-Neto and Kellner (1988), and subsequently refigured by Kellner et al. (1991) and Kellner (2002). Martill and Filgueira (1994) later described a semiplume, while Kellner et al. (1994) reported the occurrence of an isolated down feather. Several other feathers have since been reported from the Crato Formation (Kellner, 2002). Avian skeletal remains, although known from anecdotal accounts and personal observations, have yet to be reported in the literature and two examples are figured here for the first time (Plate 25d, Plate 26). Isolated feathers occur in both the weathered, buff-coloured laminated limestone as goethite pseudomorphs, and as carbonaceous replicas in the unweathered limestones. Specimens preserved as carbonaceous replicas may be represented by bacterial autolithifications (Martill and Frey, 1995), and in this respect the preservation mirrors that of the famous soft-tissue fossils of the Eocene Messel Formation of Germany (Wuttke, 1983). As in the case of the Crato Formation insects, fine details may be preserved in the feathers, despite the bacterial autolithification. In some cases colour patterns appear to have been preserved; in most instances as dark and light transverse bands (Plate 25). Although it has been possible to categorize these isolated feathers by comparison with modern feather morphotypes, it has not been possible to assign them to any particular taxon.
A fossil feather preserved as a carbonised trace is described from the Tomaj Limestone at Križ, in the Kras region of southwestern Slovenia. The Tomaj Limestone is a platy and laminated limestone with cherts, which occurs within a well-bedded rudist limestone of the Santonian–Campanian Lipica Formation. It was deposited in a lagoon environment and has yielded a diverse fossil assemblage. Whether this feather belonged to a bird or to a dinosaur is unclear, but it is an addition to the scanty record of Late Cretaceous feathers, from a palaeobiogeographically interesting area.
A fossil feather found from the Late Pleistocene sediments of Jeju Island, Korea is described. The sediments deposited in a shallow marine environment yielded numerous footprints of diverse birds and mammals including hominids. A fossil feather well-preserved as a thin white film on the light gray mudstone is part of a vaned flight one. Although the specimen is relatively small in size (10.3 mm long and 9.0 mm wide), a rachis with two flat vanes and nearly parallel curved barbs with numerous proximal and distal barbules are well preserved. The specimen represents the first record of a fossil feather from Korea and is also the first record of feather from the Pleistocene deposits in the world.
More than half of the evolutionary history of birds is played out in the Mesozoic. A recent burst of fossil discoveries has documented a tremendous diversity of early avians. Clarification of the Phylogenetic structure of this diversity has provided clues for a better understanding of the evolution of functional, developmental and physiological characteristics of modern birds. Yet their long Mesozoic history is only beginning to be deciphered.
An Early Cretaceous (Aptian) fossil feather has been discovered in the Araipe Basin, northeast Brazil. Its features, including an overall fluffy aspect, indicate that it is a definitive down feather. This new material provides empirical evidence that birds had already developed an effective thermoregulatory insulation cover, with down feathers, by the Early Cretaceous. Furthermore, in the absence of skeletal remains, the fossil feathers are the only reliable evidence of Mesozoic birds in Brazil. -Authors
A semi-plume feather from the Nova Olinda Member of the Crato Formation (Aptian, Lower Cretaceous) of north-east Brazil is only the second feather reported from this remarkable lagerstatte. The new specimen is presumed to be preserved as an organic film in organic-rich, laminated limestones, and is from an unknown bird probably in the size range 150 to 300 mm. -Authors
Unrelated taxa of feather mites use exuviae of their own, or closely related, species for molting within quills or on feather surfaces of diverse groups of birds. On the Orange-fronted Conure [Aratinga canicularis (L.)] and other parrot species, feather mites and mallophagan eggs coinhabit the same feather area, mites molt within the exuviae of other mites within the mallophagan egg shells. Molting within exuviae and within egg shells are examples of thanatochresis (the use of dead parts of one animal by living individuals of a second species, but not for food); this phenomenon may be common among feather mites and other Astigmata.
Unusually well preserved fossil feathers from Lower Cretaceous (VaIanginian-Aptian) claystones at Koonwarra, Victoria, are the oldest (c. 110-125 million years) bird remains yet found in the southern hemisphere, They are among the oldest bird remains known in the world, being antedated only by the toothed Archaeopteryx from the late Jurassic of Bavaria, and being more or less the same age as Gallornis from the Lower Cretaceous of France. The Victorian fossil feathers are evidence for essentially worldwide distribution of birds soon after the beginning of the Cretaceous, if not before. The feathers could conceivably have come from toothed birds.