Mechanisms of trophic niche compression: Evidence from landscape disturbance DOI
Francis J. Burdon, Angus R. McIntosh, Jon S. Harding

et al.

Journal of Animal Ecology, Journal Year: 2019, Volume and Issue: 89(3), P. 730 - 744

Published: Nov. 6, 2019

Natural and anthropogenic disturbances commonly alter patterns of biodiversity ecosystem functioning. However, how networks interacting species respond to these changes remains poorly understood. We described aquatic food webs using invertebrate fish community composition, functional traits stable isotopes from twelve agricultural streams along a landscape disturbance gradient. predicted that excessive deposition fine inorganic sediment (sedimentation) associated with activities would negatively influence trophic diversity (e.g. reduced vertical horizontal niche breadths). hypothesized multiple mechanisms might cause 'compression', as indicated by in realized roles. Food-web properties based on consumer isotope data (δ13 C δ15 N) showed increasing was diversity. In particular, the occupied smaller area isotopic space sedimentation gradient best explained narrowing δ13 range. Decreased partitioning, driven habitat homogeneity, environmental filtering resource scarcity all seemingly lead greater equivalency caused collapse autochthonous food-web channel. Bayesian mixing-model analyses supported this contention consumers increasingly reliant detritus gradient, predatory invertebrates relying more prey basal resources. The range contributed an apparent 'trophic shift' towards terrestrial carbon, further indicating loss On axis, became separated increase their estimated position. combination, responses were most likely mediated through densities diminished reliance prey. Although losses remain major threat integrity, roles biota persist dictate functioning change. Sedimentation nonlinear reductions which could affect stability ecosystems. Our study helps explain may radically reshape response type disturbance.

Language: Английский

Improving Marine Ecosystem Models with Biochemical Tracers DOI Open Access
Heidi Pethybridge, C. Anela Choy,

Jeffrey J. Polovina

et al.

Annual Review of Marine Science, Journal Year: 2018, Volume and Issue: 10(1), P. 199 - 228

Published: Jan. 3, 2018

Empirical data on food web dynamics and predator-prey interactions underpin ecosystem models, which are increasingly used to support strategic management of marine resources. These have traditionally derived from stomach content analysis, but new complementary forms ecological available biochemical tracer techniques. Extensive opportunities exist improve the empirical robustness models through incorporation indices, an area that is rapidly expanding because advances in analytical developments sophisticated statistical Here, we explore trophic information required by model frameworks (species, individual, size based) match them most commonly tracers (bulk tissue compound-specific stable isotopes, fatty acids, trace elements). Key quantitative parameters include estimates diet composition, niche width, position. Biochemical also provide powerful insight into spatial temporal variability structure characterization dominant basal microbial groups. A major challenge incorporating scale type mismatches, can be overcome with greater knowledge exchange numerical approaches transform, integrate, visualize data.

Language: Английский

Citations

84

Resolving Food-Web Structure DOI Creative Commons
Robert M. Pringle, Matthew C. Hutchinson

Annual Review of Ecology Evolution and Systematics, Journal Year: 2020, Volume and Issue: 51(1), P. 55 - 80

Published: July 31, 2020

Food webs are a major focus and organizing theme of ecology, but the data used to assemble them deficient. Early debates over food-web focused on taxonomic resolution completeness, lack which had produced spurious inferences. Recent widely believed be much better extensively in theoretical meta-analytic research network ecology. Confidence these rests assumptions ( a) that empiricists correctly identified consumers their foods b) sampling methods were adequate detect near-comprehensive fraction trophic interactions between species. Abundant evidence indicates often invalid, suggesting most topological may remain unreliable for inferences about structure underlying ecological evolutionary processes. Morphologically cryptic species ubiquitous across taxa regions, many routinely evade detection by conventional methods. Molecular have diagnosed severity problems necessary part cure.

Language: Английский

Citations

84

Meta‐analysis and critical review of trophic discrimination factors (Δ13C and Δ15N): Importance of tissue, trophic level and diet source DOI
Ryan B. Stephens, Oliver N. Shipley, Remington J. Moll

et al.

Functional Ecology, Journal Year: 2023, Volume and Issue: 37(9), P. 2535 - 2548

Published: July 18, 2023

Abstract Robustly quantifying dietary resource use and trophic position using stable isotopes requires accurate discrimination factors (TDF; Δ 13 C 15 N for carbon nitrogen, respectively), defined as the isotopic difference between consumer diet. Early TDF studies converged on values of around 1.0‰ 3.4‰ but more recent work indicates that may be nuanced, depending taxa, tissues, level diets. Yet, relative importance these remains unclear. Focusing vertebrates (birds, fish, herptiles mammals), we conducted a literature review 279 estimated used Bayesian framework to determine how tissue type, diet source influence variation in N. Additionally, reviewed 358 ecology if accounted during their selection process. For C, showed consistent patterns among types (likely influenced by amino acid composition) levels sources result protein content metabolic routing). Comparatively, N, considerable levels, likely due differences synthesis physiological capabilities. Overall, ranged from −5.1‰ 9.1‰ −3.3‰ 9.7‰, underscoring are not universally appropriate. Moreover, both varied than 9‰ within single species demonstrating same, or similar, appropriate considered. Despite values, most did account it. Further, fish relied failed source. To aid ecologists assessments vertebrates, our meta‐analysis model taxon‐specific estimates (mean ± SD) each combination. These refined should improve ecological isotopes. Read free Plain Language Summary this article Journal blog.

Language: Английский

Citations

28

The power and pitfalls of amino acid carbon stable isotopes for tracing origin and use of basal resources in food webs DOI Creative Commons
Kim Vane, Matthew R. D. Cobain, Thomas Larsen

et al.

Ecological Monographs, Journal Year: 2025, Volume and Issue: 95(1)

Published: Jan. 22, 2025

Abstract Natural and anthropogenic stressors alter the composition, biomass, nutritional quality of primary producers microorganisms, basal organisms that synthesize biomolecules essential for metazoan growth survival (i.e., resources). Traditional biomarkers have provided valuable insight into spatiotemporal dynamics resource use, but lack specificity in identifying multiple organisms, can be confounded by environmental physiological processes, do not always preserve tissues over long timescales. Carbon stable isotope ratios amino acids (δ 13 C‐EAA) show remarkable promise distinguishing clades with unique δ C‐EAA fingerprints are independent trophic processing variability, providing unparalleled potential their application. Understanding biochemical processes underpin C‐AA data is crucial, however, holistic robust inferences ecological applications. This comprehensive methodological review, first time, conceptualizes these mechanistic underpinnings drive among incorporates C values non‐essential generally overlooked studies, despite gain metabolic information. We conduct meta‐analyses published to test hypothesized AA‐specific fractionations organism clades, demonstrating phenylalanine separates vascular plant fingerprints, which strongly covaries phylogeny. further explore utility AAs separating dietary protein sources archaeological humans, showing differences information contained within different NEAAs. By scrutinizing many methodologies applied field, we highlight absence standardized analytical protocols, particularly sample pretreatments leading biases, inappropriate use statistical methods, reliance on unsuitable training data. To unlock full provide in‐depth explanations knowledge gaps, pitfalls, optimal practices this complex powerful approach assessing ecosystem change across scales.

Language: Английский

Citations

1

Assessing changes in arthropod predator–prey interactions through DNA‐based gut content analysis—variable environment, stable diet DOI
Bernhard Eitzinger, Nerea Abrego, Dominique Gravel

et al.

Molecular Ecology, Journal Year: 2018, Volume and Issue: 28(2), P. 266 - 280

Published: Sept. 19, 2018

Analysing the structure and dynamics of biotic interaction networks processes shaping them is currently one key fields in ecology. In this paper, we develop a novel approach to gut content analysis, thereby deriving new perspective on community interactions their responses environment. For this, use an elevational gradient High Arctic, asking how environment species traits interact predator-prey involving wolf spider Pardosa glacialis. To characterize potential prey available predator, used pitfall trapping vacuum sampling. actually consumed, applied molecular analysis. Using joint distribution models, found elevation vegetation mass explain most variance composition locally available. However, such environmental variables had only small effect spider's gut. These observations indicate that exerts selective feeding particular taxa irrespective constraints. By directly modelling probability predation based data, neither trait matching terms predator body size nor phylogenetic or constraints modified probability. Our results taxonomic identity may be more important for than traits. The impact change thus appears indirect mediated by its imprint prey.

Language: Английский

Citations

80

One‐locus‐several‐primers: A strategy to improve the taxonomic and haplotypic coverage in diet metabarcoding studies DOI Creative Commons
Emmanuel Corse, Christelle Tougard, Gaït Archambaud‐Suard

et al.

Ecology and Evolution, Journal Year: 2019, Volume and Issue: 9(8), P. 4603 - 4620

Published: March 18, 2019

In diet metabarcoding analyses, insufficient taxonomic coverage of PCR primer sets generates false negatives that may dramatically distort biodiversity estimates. this paper, we investigated the and complementarity three cytochrome c oxidase subunit I gene (COI) based on in silico analyses conducted an vivo evaluation using fecal spider web samples from different invertivores, environments, geographic locations. Our results underline lack predictability both individual sets: (a) sharp discrepancies exist observed between (to detriment analyses); (b) depend greatly predator level at which preys are considered; (c) sets' is greatest fine levels (molecular operational units [MOTUs] variants). We then formalized "one-locus-several-primer-sets" (OLSP) strategy, is, use several target same locus (here first part COI gene) group taxa invertebrates). The proximal aim OLSP strategy to minimize by increasing total through multiple sets. illustrate especially relevant perspective since distinct variants within MOTUs were not equally detected across all Furthermore, produces largely overlapping comparable sequences, cannot be achieved when targeting loci. This facilitates haplotypic diversity information contained datasets, for example, phylogeography finer prey-predator interactions.

Language: Английский

Citations

75

Pterosaur dietary hypotheses: a review of ideas and approaches DOI Creative Commons
Jordan Bestwick, David M. Unwin, Richard J. Butler

et al.

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2018, Volume and Issue: 93(4), P. 2021 - 2048

Published: June 7, 2018

ABSTRACT Pterosaurs are an extinct group of Mesozoic flying reptiles, whose fossil record extends from approximately 210 to 66 million years ago. They were integral components continental and marginal marine ecosystems, yet their diets remain poorly constrained. Numerous dietary hypotheses have been proposed for different pterosaur groups, including insectivory, piscivory, carnivory, durophagy, herbivory/frugivory, filter‐feeding generalism. These hypotheses, subsequent interpretations diet, supported by qualitative (content fossils, associations, ichnology, comparative anatomy) and/or quantitative (functional morphology, stable isotope analysis) evidence. Pterosaur scattered throughout the literature with little attention paid supporting Reaching a robustly consensus on is important understanding evolution, roles in ecosystems. A comprehensive examination identified 314 (dietary statement plus evidence) 126 published studies. Multiple alternative hypothesised most principal taxonomic groups. Some groups exhibit high degree consensus, multiple lines evidence, while others less consensus. Qualitative evidence supports 87.3% interpretations, anatomy common (62.1% total). More speciose tend greater range diets. Consideration within phylogenetic contexts reveals levels between equivalent monofenestratan lower non‐monofenestratan Evaluating possible non‐biological controls apparent patterns diversity that numbers through time no correlation publication (number peer‐reviewed publications time). 73.8% 21st century. Overall, better accounted signals, such as impact respective quality research levels. That many based qualitative, often untestable adds significant noise data. experiment‐led research, consideration pterosaurs organisms independent evolutionary histories, will lead more robust conclusions drawn repeatable results. This allow diversity, disparity evolution facilitate reconstructions

Language: Английский

Citations

69

Resolving resource partitioning in parrotfishes (Scarini) using microhistology of feeding substrata DOI
Georgina M. Nicholson, Kendall D. Clements

Coral Reefs, Journal Year: 2020, Volume and Issue: 39(5), P. 1313 - 1327

Published: June 9, 2020

Language: Английский

Citations

68

Assessment of Animal-Based Methods Used for Estimating and Monitoring Rangeland Herbivore Diet Composition DOI Creative Commons
Sarah Garnick, Perry S. Barboza, John W. Walker

et al.

Rangeland Ecology & Management, Journal Year: 2018, Volume and Issue: 71(4), P. 449 - 457

Published: April 26, 2018

Researchers and managers need effective tools for monitoring the use of forages by large herbivores. Since 2000, number herbivore diet studies has nearly doubled. In this review, we determine trends in field; assess utility key techniques against five criteria (cost, accuracy precision, resolution, long-term programs, appropriateness browsers grazers); make recommendations to give appropriate tools. Three stand out: microhistology, near infrared reflectance spectroscopy, deoxyribonucleic acid (DNA) barcoding. Microhistology a long history rangelands is often considered gold standard understanding composition, albeit at high cost labor. Near spectroscopy can resolve presence target groups or species more quickly than especially grazers. DNA barcoding provides greatest resolution dietary items with less quantitative certainty microhistology. The costs associated come primarily from technology sequencing, while microhistology they are Therefore, an improved, streamlined method could provide rangeland rapid cost-effective monitoring. Ultimately, complex challenges facing today may require one achieve acceptable within actionable time frames.

Language: Английский

Citations

64

There's no harm in having too much: A comprehensive toolbox of methods in trophic ecology DOI
Nabil Majdi, Nicolas Hette‐Tronquart,

Etienne Auclair

et al.

Food Webs, Journal Year: 2018, Volume and Issue: 17, P. e00100 - e00100

Published: Sept. 14, 2018

Language: Английский

Citations

63