Empirical evidence of type III functional responses and why it remains rare

Frontiers in Ecology and Evolution, Год журнала: 2023, Номер 11

Опубликована: Март 10, 2023

More than 70 years after its introduction, the framework of resource density-dependent consumption rates, also known as predator-prey functional responses, remains a core concept in population and food web ecology. Initially, three types responses were defined: linear (type I), hyperbolic II), sigmoid III). Due to potential stabilize consumer-resource dynamics, type III response immediately became “holy grail” However, experimentally proving that exist, whether controlled laboratory systems or nature, was challenging. While theoretical practical advances make identifying easier today, decades research have brought only limited number studies provide empirical evidence for curves. Here, we review this from laboratory- field-based published during last two decades. We found 107 reported but these ranged across various taxa, interaction types, ecosystems. To put into context, discuss biological mechanisms may lead emergence responses. summarize how different mutually independent intricacies bedevil documentation responses: (1) challenges statistical modeling (2) inadequate density ranges spacing, (3) biologically meaningful realistic design experimental arenas. Finally, guidelines on field should move forward based considerations.

Язык: Английский

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Widespread analytical pitfalls in empirical coexistence studies and a checklist for improving their statistical robustness

Methods in Ecology and Evolution, Год журнала: 2024, Номер 15(4), С. 594 - 611

Опубликована: Фев. 28, 2024

Abstract Modern coexistence theory (MCT) offers a conceptually straightforward approach for connecting empirical observations with an elegant theoretical framework, gaining popularity rapidly over the past decade. However, beneath this surface‐level simplicity lie various assumptions and subjective choices made during data analysis. These can lead researchers to draw qualitatively different conclusions from same set of experiments. As predictions MCT studies are often treated as outcomes, many readers reviewers may not be familiar framework's assumptions, there is particular risk ‘researcher degrees freedom’ inflating confidence in results, thereby affecting reproducibility predictive power. To tackle these concerns, we introduce checklist consisting statistical best practices promote more robust applications MCT. Our recommendations organised into four categories: presentation sharing raw data, testing model fits, managing uncertainty associated coefficients incorporating predictions. We surveyed published 15 years discovered high degree variation level rigour adherence practices. present case illustrate dependence results on seemingly innocuous among competition structure error distributions, which some cases reversed predicted outcomes. demonstrate how analytical approaches profoundly alter interpretation experimental underscoring importance carefully considering thoroughly justifying each step taken analysis pathway. serves resource authors alike, providing guidance strengthen foundation analyses. field shifts descriptive, trailblazing phase stage consolidation, emphasise need caution when building upon findings earlier studies. ensure that progress ecological based reliable evidence, it crucial subject our predictions, generalisability rigorous assessment than currently trend.

Язык: Английский

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The rise of the Functional Response in invasion science: a systematic review

NeoBiota, Год журнала: 2023, Номер 85, С. 43 - 79

Опубликована: Июнь 9, 2023

Predicting which non-native species will negatively impact biodiversity is a longstanding research priority. The Functional Response (FR; resource use in relation to availability) classical ecological concept that has been increasingly applied quantify, assess and compare impacts of species. Despite this recent growth, an overview applications knowledge gaps across relevant contexts currently lacking. We conducted systematic review using combination terms regarding FR invasion science synthesise scientific studies apply the approach field suggest new areas where it could have valuable applications. Trends publications about general were compared through Activity Index. Data extracted from papers reveal temporal, bibliographic, geographic trends, patterns study attributes such as type interaction habitat investigated, taxonomic groups used, context-dependencies assessed. In total, 120 included review. identified substantial unevenness reporting FRs science, despite rapidly growing number studies. To date, geographically skewed towards North America Europe, well predator-prey interactions freshwater habitats. Most focused on few invertebrates fishes. Species origin, life stage, environmental temperature complexity most frequently considered context-dependencies. conclude while thus far narrowly applied, broad potential application can be used test major hypotheses field.

Язык: Английский

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Predator-mediated interactions through changes in predator home range size can lead to local prey exclusion

Proceedings of the Royal Society B Biological Sciences, Год журнала: 2023, Номер 290(2004)

Опубликована: Авг. 9, 2023

The strength of indirect biotic interactions is difficult to quantify in the wild and can alter community composition. To investigate whether presence a prey species affects population growth rate another species, we quantified predator-mediated interaction using multi-prey mechanistic model predation matrix model. Models were parametrized behavioural, demographic experimental data from vertebrate that includes arctic fox (

Язык: Английский

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Darwinian evolution as a dynamical principle

Proceedings of the National Academy of Sciences, Год журнала: 2023, Номер 120(11)

Опубликована: Март 7, 2023

Darwinian evolution (DE)—biology’s powerful process of adaptation—is remarkably different from other known dynamical processes. It is antithermodynamic, driving away equilibrium; it has persisted for 3.5 billion years; and its target, fitness, can seem like “Just So” stories. For insights, we make a computational model. In the Evolution Machine (DEM) model, resource-driven duplication competition operate inside cycle search/compete/choose. We find following: 1) DE requires multiorganism coexistence long-term persistence ability to cross fitness valleys. 2) driven by resource dynamics, booms busts, not just mutational change. And, 3) ratcheting mechanistic separation between variation selection steps, perhaps explaining biology’s use separate polymers, DNA proteins.

Язык: Английский

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Origins of life: first came evolutionary dynamics

QRB Discovery, Год журнала: 2023, Номер 4

Опубликована: Янв. 1, 2023

Abstract When life arose from prebiotic molecules 3.5 billion years ago, what came first? Informational (RNA, DNA), functional ones (proteins), or something else? We argue here for a different logic: rather than seeking molecule type , we seek dynamical process. Biology required an ability to evolve before it could choose and optimise materials. hypothesise that the evolution process was rooted in peptide folding Modelling shows how short random peptides can collapse water catalyse elongation of others, powering both increased stability emergent autocatalysis through disorder-to-order

Язык: Английский

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Trophic tug‐of‐war: Coexistence mechanisms within and across trophic levels

Ecology Letters, Год журнала: 2024, Номер 27(4)

Опубликована: Апрель 1, 2024

Abstract Ecological communities encompass rich diversity across multiple trophic levels. While modern coexistence theory has been widely applied to understand community assembly, its traditional formalism only allows assembly within a single level. Here, using an expanded definition of niche and fitness differences applicable multitrophic communities, we study how levels affects species coexistence. If each level is analysed separately, both lower‐ higher are governed by the same mechanisms. In contrast, if as whole, different mechanisms: at lower predominantly limited differences, whereas differences. This dichotomy in mechanisms supported theoretical derivations, simulations phenomenological trait‐based models, case primeval forest ecosystem. Our work provides general testable prediction mechanism operating communities.

Язык: Английский

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In defense of the Type I functional response: The frequency and population-dynamic effects of feeding on multiple prey at a time

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Май 17, 2024

Abstract Ecologists differ in the degree to which they consider linear Type I functional response be an unrealistic versus sufficient representation of predator feeding rates. Empiricists tend it unsuitably non-mechanistic and theoreticians necessarily simple. Holling’s original rectilinear model is dismissed by satisfying neither desire, with most compromising on smoothly saturating II for searching handling are assumed mutually exclusive activities. We derive a “multiple-prey-at-a-time” generalization that includes III reflect predators can continue search when arbitrary number already-captured prey. The multi-prey clarifies empirical relevance models conditions under linearity mechanistically-reasoned description rates, even times long. find support presence 35% 2,591 compiled datasets, evidence larger predator-prey body-mass ratios permit while greater numbers Incorporating into Rosenzweig-MacArthur population-dynamics reveals non-exclusivity lead coexistence states dynamics not anticipated theory built traditional models. In particular, bistable fixed-point limit-cycle long-term crawl-by transients between them where abundance top-heavy food webs linear. conclude should considered empirically but also more bounded conclusions drawn presuming appropriate.

Язык: Английский

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Towards understanding interactions in a complex world: Design and analysis of multi‐species functional response experiments

Methods in Ecology and Evolution, Год журнала: 2024, Номер 15(9), С. 1704 - 1719

Опубликована: Июнь 23, 2024

Abstract The functional response describes feeding rates of consumers as a function resource density. While models for on single species are well studied and supported by large body empirical research, multiple ubiquitous in nature. However, laboratory experiments designed parameterizing multi‐species responses (MSFR) extremely rare, mainly due to logistical challenges the non‐trivial nature their statistical analysis. Here, we describe how these can be fitted data Bayesian framework. Specifically, address problem prey depletion during experiments, which accounted through dynamical modelling. In comprehensive simulation study, test effects experimental design, sample size noise level identifiability four distinct MSFR models. Additionally, demonstrate method's versatility applying it list datasets. We identify designs trials that produce most accurate parameter estimates two‐ three‐prey scenarios. Although introduces systematic bias estimates, model selection performs surprisingly MSFRs, almost always identifying correct even small This flexible framework allows simultaneous analysis from both single‐ multi‐prey scenarios, either with or without depletion. will help elucidate mechanisms such selectivity, switching implications food web stability biodiversity. Our approach equips researchers appropriate tools improve understanding interactions complex ecosystems.

Язык: Английский

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Hidden layers of density dependence in consumer feeding rates

Ecology Letters, Год журнала: 2021, Номер 24(3), С. 520 - 532

Опубликована: Янв. 6, 2021

Abstract Functional responses relate a consumer's feeding rates to variation in its abiotic and biotic environment, providing insight into consumer behaviour fitness, underpinning population food‐web dynamics. Despite their broad relevance long‐standing history, we show here that the types of density dependence found classic resource‐ consumer‐dependent functional‐response models equate strong often untenable assumptions about independence processes underlying rates. We first demonstrate mathematically how quantify non‐independence between interference on multiple resources. then analyse two large collections data sets is pervasive borne out previously hidden forms dependence. Our results provide new lens through which view disentangle biological underpinnings species interactions multi‐species contexts.

Язык: Английский

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