Prey choice and cannibalistic behaviour in the theropod
            Coelophysis

Abstract Direct evidence of prey choice in carnivorous dinosaurs is rare in the fossil record. The most celebrated example pertains to purported stomach contents in the carnivorous dinosaur Coelophysis bauri , which besides revealing prey choice, also points to cannibalistic behaviour as being commonplace ( Colbert 1989 , 1995). Here, we test this hypothesis by conducting the first comprehensive anatomical and histological examination of the famed Coelophysis ‘cannibals’. The results unequivocally show that the gut contents derive from early crocodylomorphs rather than juveniles of Coelophysis . These findings suggest that this taxon is not cannibalistic and bring into question the commonality of this behaviour among non-avian dinosaurs.

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Plankton food for benthic fish: de visu evidence of trophic interaction between rainbow wrasse (Coris julis) and pelagic tunicates (Pegea confoederata)

Advances in Oceanography and Limnology ◽

10.4081/aiol.2017.6973 ◽

2017 ◽

Vol 8 (2) ◽

Cited By ~ 2

Author(s):

Domenico D'Alelio ◽

Gabriella Luongo ◽

Iole Di Capua

Keyword(s):

Trophic Interactions ◽

Direct Evidence ◽

Stomach Contents ◽

Trophic Interaction ◽

Benthic Fish ◽

Marine Animals ◽

Gulf Of Naples ◽

Santa Croce ◽

Rocky Outcrop ◽

Recreational Scuba

Salps (pelagic tunicates) are rarely observed in nature and trophic interactions involving them mainly rely on the inspection of stomach contents of their potential predators. Moreover, salps have soft bodies that are hardly identified in potential consumers. We involved recreational SCUBA-divers and photographers in collecting de visu evidence of i) massive occurrence of salps and ii) trophic interactions involving salps as preys and benthic animals as consumers. Direct evidence of trophic interactions between salps and benthic fish was documented by photographic frames. We detected a long colony of the salp Pegea confaederata being transported by currents close to the substrate on top of Banco di Santa Croce, an underwater rocky outcrop in the Gulf of Naples (Italy). An individual of the rainbow wrasse Coris julis attacked the above-mentioned salp colony by selectively detaching individuals and biting their stomach. Our report of a trophic interaction between labrids and salps is the second in fifty years and the previous one was only indirect. In this study, citizen science allowed detecting both neglected marine animals like salps and trophic interactions involving them. Visual, direct evidence of predation on salps by benthic fish adds further knowledge about patterns of living-matter fluxes between plankton and benthos, opening new questions on the potential of global change in modifying the efficient circulation of organic matter in marine systems.

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Naticid gastropod and octopodid cephalopod predatory traces: evidence of drill holes on the leucosid crab Ristoria pliocaenica (Ristori, 1891), from the Pliocene of the “La Serra” quarry (Tuscany, Italy)

Natural History Sciences ◽

10.4081/19 ◽

2012 ◽

Vol 153 (2) ◽

pp. 257 ◽

Cited By ~ 2

Author(s):

Giovanni Pasini ◽

Alessandro Garassino

Keyword(s):

Fossil Record ◽

Direct Evidence ◽

Central Italy ◽

Decapod Crustaceans ◽

Early Pliocene ◽

First Report ◽

Predatory Activity ◽

The Common ◽

Drill Holes

Garassino et al. (2012) reported on a rich community of decapod crustaceans including axiideans, gebiideans, anomurans, and brachyurans from the Zanclean (Early Pliocene) of the “La Serra” quarry near San Miniato (Pisa, Tuscany, central Italy). In this decapod-rich assemblage some carapaces of the common pebble crab Ristoria pliocaenica (Ristori, 1891) (Leucosiidae Samouelle, 1819) are drilled in characteristic ways, due to the predatory activity of individuals belonging to two different taxa of marine clades, possibly naticids (Gastropoda, Naticoidea), and to octopodids (Cephalopoda, Octopoda). This is the first report of direct evidence of predation by cephalopods on crabs in the fossil record.

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Termitivore or detritivore? A quantitative investigation into the diet of the East African caecilian Boulengerula taitanus (Amphibia: Gymnophiona: Caeciliidae)

Animal Biology ◽

10.1163/157075604323010042 ◽

2004 ◽

Vol 54 (1) ◽

pp. 45-56 ◽

Cited By ~ 27

Author(s):

G. John Measey ◽

Olivier Gaborieau

Keyword(s):

Organic Matter ◽

Stomach Contents ◽

Gut Contents ◽

Generalist Predators ◽

East African ◽

Quantitative Investigation ◽

Soil Macrofauna ◽

Taita Hills ◽

Specialist Predators ◽

African Genus

AbstractMost caecilians are thought to be generalist predators of soil ecosystem engineers (earthworms, termites and ants), but it has been suggested that members of the East African genus Boulengerula are specialist predators. Surprisingly, in the only detailed study of diet of any Boulengerula, the authors speculated that B. taitanus is partly detritivorous, based on the large amount of organic matter found in the alimentary canal. Here we test the conflicting hypotheses that B.taitanus is a termitivore or detritivore, using the stomach and gut contents of 47 specimens collected in the Taita Hills, Kenya. Termites and earthworms contribute most significantly to diet by number and mass, respectively. These constitute the major dietary items, together with dipteran larvae and other soil macrofauna. Contents of the intestine are mostly soil and organic matter originating from prey items. The mass content of the intestines averages 69% of total gut contents, and is significantly greater than identifiable stomach contents. The null hypotheses that B. taitanus is a generalist and a predator are not rejected.

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The Ecology of the Eastern Water Rat Hydromys Chrysogaster at Griffith, N.s.w.: Food and Feeding Habits.

Wildlife Research ◽

10.1071/wr9780059 ◽

1978 ◽

Vol 5 (1) ◽

pp. 59 ◽

Cited By ~ 23

Author(s):

P Woollard ◽

WJM Vestjens ◽

L Maclean

Keyword(s):

Plant Material ◽

Feeding Habits ◽

Starch Content ◽

South Australia ◽

Stomach Contents ◽

Freshwater Mussel ◽

Time Of Day ◽

Gut Contents ◽

South Wales ◽

Hydromys Chrysogaster

The eastern water rat, Hydromys chrysogaster, lives in inland waters, estuaries, sea beaches and islands from Queensland to South Australia and Tasmania. It is adapted to semiaquatic life and changes in its molar teeth may be an adaptation to diet of crustaceans and molluscs. The present study was of 408 stomach contents and 316 contents of caecum with rectum, collected in New South Wales in 1970-73 from permanent Typha swamp. From elsewhere there were 12 other stomach and 11 gut contents and live rats were observed. At any time of day but particularly in evenings the rats swam along the bank or between logs or reed clumps, foraging and catching fish. Captive rats crushed small mussels and left large mussels to open by exposure. Diet varied with season and included crustaceans, mostly the yabbie, a crayfish (Cherax destructor), spiders, all Araneida with one identified as of the suborder Pisauridae, a fishing spider. Insects were the main food and were eaten in all seasons, and included larvae, nymphs and adults. Only 1% of rats had the freshwater mussel Veksurio ambiguus but the flesh was difficult to identify and empty shells were often found. Fish were eaten all the year, and were found in up to 35% of rats in autumn and winter; fish may be underestimated because flesh is not easily recognised and hard parts are not much eaten. Several species of fish, mostly introduced, were identified, their ages estimated from their scales, and length was calculated to be up to 36 cm. Frogs and macquaria tortoise (Emydura macquarii) were eaten. Birds were eaten all the year and were in up to 10% of stomachs in winter. Personal communications are quoted, from persons having seen H. chrysogaster capture large adult birds including duck and mutton bird (Puffinus tenuirostris). Captive rats were able to open cracked hen's eggs but left intact eggs. Plant material was eaten as food and possibly also in stomachs of prey. For 3 rats half the starch content was plant; 3 other stomachs had 5, 40 and 50% plant material, Azolla fuliculoides. Differences in diet with age are described. H. chrysogaster was an adaptable and opportunist feeder, making use of transient plenty of insects, exploiting plagues among other species and using plants during shortage of food. They may control introduced pests such as perch, or control yabbies in irrigation ditches.

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Variability in the diet diversity of catfish highlighted through DNA barcoding

10.1101/2020.09.18.268888 ◽

2020 ◽

Cited By ~ 1

Author(s):

Chinnamani Prasannakumar ◽

Gunasekaran Iyyapparajanarasimapallavan ◽

M. Ashiq Ur Rahman ◽

P. Mohanchander ◽

T. Sudhakar ◽

...

Keyword(s):

Dna Barcoding ◽

Monsoon Season ◽

Stomach Contents ◽

Hermit Crabs ◽

Gut Contents ◽

Reference Database ◽

Perna Viridis ◽

Fish Diet ◽

Diet Diversity ◽

Post Monsoon

AbstractIdentification and quantification of fish diet diversity was the first step in understanding the food web dynamics and ecosystem energetics, where the contribution of DNA barcoding technique has been important. We used DNA barcoding to identify the stomach contents of a euryhaline, benthophagous catfish Ariius maculatus. From 40 catfish stomach items sampled in two different seasons, we barcoded 67 piscine and macro-invertebrates prey items, identified as belonging to 13 species in 4 major phyla (viz., Chordate, Arthropod, Annelida and Mollusca). It is important to note that the mollusc taxa (Meritrix meritrix and Perna viridis) and a species of fish (Stolephorus indicus) could not be found among the gut contents of A. maculatus sampled during the pre- and post-monsoon season, respectively. Among the piscine diets of A. maculatus, Eubleekeria splendens (23.5%) and Stolephorus indicus (23.5%) were the major prey taxa during pre-monsoon season. The hermit crabs forms the major constituents of both pre- and post-monsoon seasons, among invertebrate taxa. Polychaete, Capitella capitata (25.92%) was abundantly consumed invertebrates next to hermit crabs. We noticed that in pre-monsoon A. maculatus was more piscivorous than post-monsoon. As revealed through Kimura-2 parametric pairwise distance analysis, the diet diversity was relatively higher in post-monsoon. The accumulation curve estimated 57 haplotypes within 14 barcoded species (including the host A. maculatus). Majority of haplotypes were found among fishes (47.36%) followed by Arthropods (28.07%), Annelids (14.03%) and Mollusca (10.52%), respectively. This study also highlights that there is a growing concern about A. maculatus’s aggressive predation on commercially important stocks of fish and invertebrates. We will continue to expand the coverage of species barcoded in the reference database, which will become more significant as meta- and environmental DNA barcoding techniques become cheaper and prevalent.

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Investigating Possible Gastroliths in a Referred Specimen of Bohaiornis guoi (Aves: Enantiornithes)

Frontiers in Earth Science ◽

10.3389/feart.2021.635727 ◽

2021 ◽

Vol 9 ◽

Author(s):

Shumin Liu ◽

Zhiheng Li ◽

Alida M. Bailleul ◽

Min Wang ◽

Jingmai O’Connor

Keyword(s):

Digestive System ◽

Multidisciplinary Approach ◽

Direct Evidence ◽

Soft Tissues ◽

Indirect Evidence ◽

Stomach Contents ◽

Gastric Mill ◽

Limited Evidence ◽

X Ray ◽

Two Samples

Gastroliths, where preserved, can provide indirect evidence regarding diet in extinct avian and non-avian dinosaurs. Masses of gastroliths consistent with the presence of a gastric mill are preserved in many Early Cretaceous Jehol birds mostly belonging to the Ornithuromorpha. Gastroliths are also present in basal birds Sapeornis and Jeholornis in which herbivory is supported by direct evidence these taxa consumed seeds in the form of crop or stomach contents. Although gastroliths have been correlated with herbivory in non-avian dinosaurs, the presence of gastroliths and bone together in Ambopteryx calls this association in to question. Despite being known from greater numbers of specimens than other avian lineages, no unequivocal direct or indirect evidence of diet has been recovered from Jehol deposits for the Enantiornithes. A referred specimen of Bohaiornis guoi IVPP V17963 was described as preserving a small number of gastroliths interpreted as rangle, gastroliths whose function is cleaning the stomach in extant raptorial birds. However, based on comparison with gastroliths in other Jehol birds, it has alternatively been suggested that the identified structures are not ingested stones at all but some unusual mineral precipitate. Considering the limited evidence regarding diet in Enantiornithes and the importance of accurately identifying the traces in Bohaiornis in order to understand the enantiornithine digestive system, we extracted two samples of these purported gastroliths and explored these traces using computerized laminography scanning, scanning electron microscopy, energy dispersive x-ray spectroscopy, ground sections, and body size to gastral mass regressions. Similar analyses were conducted on gastroliths extracted from undisputed gastral masses of two Jehol ornithuromorphs and the non-avian pennaraptoran Caudipteryx. The combined results contradict the hypothesis that these traces are gastroliths and supports the interpretation they are mineral precipitate, most likely authigenic quartz (chalcedony). Although authigenesis is commonly responsible for the preservation of soft tissues, it is unclear if these traces record part of the tissues of this Bohaiornis. This study highlights the importance of a multidisciplinary approach in understanding unusual traces in the fossil record and reveal a previously unidentified taphonomic phenomenon in fossils from Jehol deposits.

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Asymmetry in the fossil record

European Review ◽

10.1017/s1062798705000712 ◽

2005 ◽

Vol 13 (S2) ◽

pp. 135-143 ◽

Cited By ~ 17

Author(s):

LOREN E. BABCOCK

Keyword(s):

Fossil Record ◽

Direct Evidence ◽

Directional Asymmetry ◽

Fundamental Aspect ◽

Lateral Asymmetry ◽

Morphological Asymmetry ◽

Fossil Evidence ◽

Behavioural Asymmetries ◽

Life On Earth ◽

Body Fossil

Asymmetry is a fundamental aspect of the biology of all organisms, and has a deep evolutionary history. The fossil record contains evidence of both morphological and behavioural asymmetries. Morphological asymmetry is most commonly expressed as conspicuous, directional asymmetry (either lateral asymmetry or spiral asymmetry) in body fossils. Few examples of fluctuating asymmetry, a form of subtle asymmetry, have been documented from fossils. Body fossil evidence indicates that morphological asymmetry dates to the time of the appearance of the first life on Earth (Archaean Eon). Behavioural asymmetry can be assumed to have been concomitant with conspicuous morphological asymmetry, but more direct evidence is in the form of trace fossils. Trace fossil evidence suggests that behavioural asymmetry, including nervous system lateralization, was in existence by the beginning of the Palaeozoic Era.

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Reanalysis of putative ovarian follicles suggests that Early Cretaceous birds were feeding not breeding

Scientific Reports ◽

10.1038/s41598-020-76078-2 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Gerald Mayr ◽

Thomas G. Kaye ◽

Michael Pittman ◽

Evan T. Saitta ◽

Christian Pott

Keyword(s):

Early Cretaceous ◽

Fossil Record ◽

Stomach Contents ◽

Ovarian Follicles ◽

Exact Nature ◽

Carbonaceous Matter ◽

Jehol Biota ◽

Food Items ◽

Micro Pattern ◽

First Time

Abstract We address the identity of putative ovarian follicles in Early Cretaceous bird fossils from the Jehol Biota (China), whose identification has previously been challenged. For the first time, we present a link to the botanical fossil record, showing that the “follicles” of some enantiornithine fossils resemble plant propagules from the Jehol Biota, which belong to Carpolithes multiseminalis. The botanical affinities of this “form-taxon” are currently unresolved, but we note that C. multiseminalis propagules resemble propagules associated with cone-like organs described as Strobilites taxusoides, which in turn are possibly associated with sterile foliage allocated to Liaoningcladus. Laser-Stimulated Fluorescence imaging furthermore reveals different intensities of fluorescence of “follicles” associated with a skeleton of the confuciusornithid Eoconfuciusornis zhengi, with a non-fluorescent circular micro-pattern indicating carbonaceous (or originally carbonaceous) matter. This is inconsistent with the interpretation of these structures as ovarian follicles. We therefore reaffirm that the “follicles” represent ingested food items, and even though the exact nature of the Eoconfuciusornis stomach contents remains elusive, at least some enantiornithines ingested plant propagules.

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New mixosaurid ichthyosaur specimen from the Middle Triassic of SW China: further evidence for the diapsid origin of ichthyosaurs

Journal of Paleontology ◽

10.1666/09-131.1 ◽

2011 ◽

Vol 85 (1) ◽

pp. 32-36 ◽

Cited By ~ 9

Author(s):

Jun Liu ◽

Jonathan C. Aitchison ◽

Yuan-Yuan Sun ◽

Qi-Yue Zhang ◽

Chang-Yong Zhou ◽

...

Keyword(s):

Fossil Record ◽

Direct Evidence ◽

Middle Triassic ◽

Evolutionary Stage ◽

Temporal Region ◽

Sw China ◽

Anterior Process ◽

Cladistic Analyses

Recent cladistic analyses have all suggested a diapsid origin of ichthyosaurs. However, an intermediate evolutionary stage of the lower temporal region of ichthyosaurian skull between basal diapsids and derived ichthyosaurs has been absent from the fossil record. Here we describe the cranial skeleton of a new mixosaurid ichthyosaur specimen with a well-preserved lower temporal region from the Anisian Guanling Formation of eastern Yunnan. It is characterized by the most primitive lower temporal region within known ichthyosaurs. The primitive characters of the lower temporal region include both external and internal separation between the jugal and the quadratojugal, an anterior process of the quadratojugal, an apparent posteroventral process of the jugal, and a large lower temporal opening surrounded by the jugal, the postorbital, the squamosal, and the quadratojugal. The lower temporal region of this specimen provides the most direct evidence to the diapsid origin of ichthyosaurs. It also suggests that the disappearance of the lower temporal fenestra is caused initially by the reduction of the lower temporal arcade rather than the enlargement of the surrounding bones.

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Feeding and schooling behaviour of barracouta (Thyrsites atun) off Otago, New Zealand

Marine and Freshwater Research ◽

10.1071/mf97074 ◽

1998 ◽

Vol 49 (1) ◽

pp. 19 ◽

Cited By ~ 4

Author(s):

Richard L. O'Driscoll

Keyword(s):

New Zealand ◽

Feeding Strategy ◽

Stomach Contents ◽

Fish Population ◽

Pelagic Fish ◽

Wild Fish ◽

Gut Contents ◽

Side Scan Sonar ◽

Schooling Behaviour ◽

The Mean

To test the hypothesis that fish in schools forage more successfully than individual fish, an analysis was made of the stomach contents of barracouta (Thyrsites atun), a facultatively schooling species of fish, in a wild fish population. Schooling (n = 29) and non-schooling (n = 86) barracouta were captured during a side-scan sonar survey of pelagic fish off the coast of Otago, New Zealand. The proportion of fish with empty stomachs was lower and the mean wet mass of gut contents was higher in barracouta from schools. The increased feeding success of fish in schools was due to increased consumption of krill, Nyctiphanes australis. In regions where the density of krill in net tows was high (>1000 individuals km-1 tow length) or moderate (100–1000 individuals km-1), the mean wet mass of krill in the stomachs of schooling barracouta was 2–4 times higher than in the stomachs of non-schooling barracouta. Few schools of barracouta were observed in areas with low densities of krill (<100 individuals km-1). Schooling by barracouta seems to be a feeding strategy to exploit surface swarms of krill.

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