22 papers · ranked by Valyu relevance
Koen J. van Benthem, Meike J. Wittmann
Population density affects fitness through various processes, such as mate finding and competition. The fitness of individuals in a population can in turn affect its density, making population density a key quantity linking ecological and evolutionary processes. Density effects are, however, rarely homogeneous.…
Crispin M. Mutshinda, Aditya Mishra, Zoe V. Finkel, Andrew J. Irwin + 1 more
'Dezene Huber'] Background Density-dependent regulation is ubiquitous in population dynamics, and its potential interaction with environmental stochasticity complicates the characterization of the random component of population dynamics. Yet, this issue has not received attention commensurate with its relevance for…
Kazutaka Kawatsu, Michio Kondoh
Ever since May theorized that communities with larger numbers of species or interspecific interactions are inherently unstable, the mechanism allowing for the stable existence of complex communities in nature has been a central question in ecology. The main efforts to answer this question have sought to identify…
Peter A. Henderson, Anne E. Magurran
To understand how ecosystems are structured and stabilized, and to identify when communities are at risk of damage or collapse, we need to know how the abundances of the taxa in the entire assemblage vary over ecologically meaningful timescales. Here, we present an analysis of species temporal variability within a…
José M. Ponciano, Mark L. Taper, Brian Dennis
Change points in the dynamics of animal abundances have extensively been recorded in historical time series records. Little attention has been paid to the theoretical dynamic consequences of such change-points. Here we propose a change-point model of stochastic population dynamics. This investigation embodies a shift…
Linh Huynh, Jacob G. Scott, Peter J. Thomas
Density dependence is important in the ecology and evolution of microbial and cancer cells. Typically, we can only measure net growth rates, but the underlying density-dependent mechanisms that give rise to the observed dynamics can manifest in birth processes, death processes, or both. Therefore, we utilize the mean…
Laure Olazcuaga, Brett. A Melbourne, Scott W. Nordstrom, Ruth A Hufbauer
Evolutionary rescue allows populations to adapt and persist despite severe environmental change. While well studied under density-independent conditions, the role of density dependence, including competition, remains unclear. Theoretical models offer conflicting predictions, with density dependence either increasing…
Jason Bertram, Joanna Masel
Selection is commonly described by assigning constant relative fitness values to genotypes. Yet population density is often regulated by crowding. Relative fitness may then depend on density, and selection can change density when it acts on a density-regulating trait. When strong density-dependent selection acts on a…
Evan C. Johnson
regulation through the lens of model uncertainty Authors: ['Evan C. Johnson'] | 1 Introduction | 4 | | --- | --- | | 2 Methods | 7 | | 3 Results | 10 | | 4 Discussion | 12 | | 5 Data availability statement | 18 | | S1 Supplementary methods | 18 | | S2 Simulation study of model selection bias | 19 | | S3 Hierarchical…
Evan C. Johnson, Alan Hastings
In this paper, we discuss the conceptual underpinnings of Modern Coexistence Theory (MCT), a quantitative framework for understanding ecological coexistence. In order to use MCT to infer how species are coexisting, one must relate a complex model (which simulates coexistence in the real world) to simple models in which…
Thibaut Morel-Journel, Marjorie Haond, Lana Duan, Ludovic Mailleret + 1 more
Demographic processes that occur at the local level, such as positive density dependence in growth or dispersal, are known to shape population range expansion by linking carrying capacity to invasion speed. As a result of these processes, the advance of an invasion front depends both on populations in the core of the…
Nathalie Jreidini, David M. Green
The relationship between animal dispersal and conspecific density has been explored in various study systems but results in terms of both the magnitude and the direction of density dependence are inconsistent. We conducted a thorough review of the literature (2000-2023) and found k = 97 empirical studies of birds…
Abhishek Mishra, Sudipta Tung, V.R. Shree Sruti, Mohammed Aamir Sadiq + 2 more
Density-dependent dispersal (DDD) has been demonstrated in many species and has several ecological and evolutionary consequences. Yet we know little about how robust DDD is to the various conditions experienced by individuals. In this study, we use three independent experiments on laboratory populations of Drosophila…
Thomas G Aubier, David Donoso, Detlef Weigel
Conspecific negative density dependence is ubiquitous and has long been recognized as an important factor favoring the coexistence of competing species at local scale. By contrast, a positive density-dependent growth rate is thought to favor species exclusion by inhibiting the growth of less competitive species. Yet…
Gregory A. Roth, Sebastian J. Schreiber
A demographic Allee effect occurs when individual fitness, at low densities, increases with population density. Coupled with environmental fluctuations in demographic rates, Allee effects can have subtle effects on population persistence and extinction. To understand the interplay between these deterministic and…
Elizabeth T. Chevy, Jiseon Min, Victoria Caudill, Samuel E. Champer + 8 more
'Benjamin C. Haller' 'Clara T. Rehmann' 'Chris C. R. Smith' 'Silas Tittes' 'Philipp W. Messer' 'Andrew D. Kern' 'Sohini Ramachandran' 'Peter L. Ralph'] Title: ABSTRACT Individual-based simulation has become an increasingly crucial tool for many fields of population biology. However, continuous geography is important to…
Alexandru Hening, Dang Nguyen, Peter Chesson
We analyze a general theory for coexistence and extinction of ecological communities that are influenced by stochastic temporal environmental fluctuations. The results apply to discrete time (stochastic difference equations), continuous time (stochastic differential equations), compact and non-compact state spaces and…
Corey J. A. Bradshaw, Salvador Herrando‐Pérez
Analysis of long-term trends in abundance of animal populations provides insights into population dynamics. Population growth rates are the emergent interplay of inter alia fertility, survival, and dispersal. However, the density feedbacks operating on some vital rates (“component feedback”) can be decoupled from…
Nicolai Machholdt Høyer, Ove Christiansen
We present a new quasi-direct quantum molecular dynamics computational method which offer a compromise between quantum dynamics using a pre-computed potential energy surface (PES) and fully direct quantum dynamics. This method is termed the time-dependent adaptive density-guided approach (TD-ADGA) and is a method for…
Authors not listed
Langmuir monolayers of dipalmitoyl phosphatidylcholine (DPPC) at air-water interfaces exhibit complex phase behavior important for pulmonary surfactant function. Despite extensive experimental and computational studies, accurately predicting their temperature-dependent properties remains challenging due to experimental…
Authors not listed
NMR chemical shifts depend on the applied magnetic flux density, and this becomes more and more important as stronger and stronger magnetic fields are becoming available. Herein, we develop a theory of the field dependence of NMR shifts of paramagnetic molecules in solution. Our derivation leads to two distinct…
Laura Eslava, Sayle Sigarreta Ricardo, Arno Siri-Jégousse
We prove that the generalized Randić index over graphs following the Erdos-Rényi model, for both the sparse and dense regimes, is concentrated around its mean when the number of vertices tends to infinity.