Demography and Big Data

Post provided by BRITTANY TELLER, KRISTIN HULVEY and ELISE GORNISH

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To understand how species survive in nature, demographers pair field-collected life history data on survival, growth and reproduction with statistical inference. Demographic approaches have significantly contributed to our understanding of population biology, invasive species dynamics, community ecology, evolutionary biology and much more.

As ecologists begin to ask questions about demography at broader spatial and temporal scales and collect data at higher resolutions, demographic analyses and new statistical methods are likely to shed even more light on important ecological mechanisms.

Population Processes

Midsummer Opuntia cactus in eastern Idaho, USA. © B. Teller.

Midsummer Opuntia cactus in eastern Idaho, USA. © B. Teller.

Traditionally, demographers collect life history data on species in the field under one or more environmental conditions. This approach has significantly improved our understanding of basic biological processes. For example, rosette size is a significant predictor of survival for plants like wild teasel (Werner 1975 – links to all articles are at the end of the post), and desert annual plants hedge their bets against poor years by optimizing germination strategies (Gremer & Venable 2014).

Demographers also include temporal and spatial variability in their models to help make realistic predictions of population dynamics. We now know that temporal variability in carrying capacity dramatically improves population growth rates for perennial grasses and provides a better fit to data than models with varying growth rates because of this (Fowler & Pease 2010). Moreover, spatial heterogeneity and environmental stochasticity have similar consequences for plant populations (Crone 2016). Continue reading

New Associate Editors

Today we are welcoming three new Associate Editors to Methods in Ecology and Evolution: Nick Golding (University of Melbourne, Australia), Rachel McCrea (University of Kent, UK) and Francesca Parrini (University of the Witwatersrand, South Africa). They have all joined on a three-year term and you can find out more about them below.

Nick Golding

Nick Golding

Nick Golding

“I develop statistical models and software for mapping the distributions of species and diseases. I’m particularly interested in tools that make it easy for researchers to add more mechanistic structure into their correlative models (and vice versa) so that they can use all available information when making predictions. I also develop software and other tools to bring research communities together and help them advance ecology by enabling and incentivising reproducible and extensible research.”

Nick has recently had an article published in Methods in Ecology and Evolution (currently in Early View). In ‘Fast and flexible Bayesian species distribution modelling using Gaussian processes‘ Nick and his co-author (Bethan Purse) introduce Gaussian process (GP) models and their application to species distribution modelling (SDM), illustrate how ecological knowledge can be incorporated into GP SDMs via Bayesian priors and formulate a simple GP SDM that can be fitted efficiently. The article is Open Access, so it’s freely available to everyone.

Rachel McCrea

Rachel McCrea

Rachel McCrea

“I am a NERC research fellow and lecturer in statistics at the University of Kent.  My particular areas of interest include capture-recapture modelling, multistate models, modelling population dynamics and methods of model assessment.  My research is motivated by interesting discussions with ecologists and I strive to find innovative, but practical statistical solutions to ecological questions.”

Rachel is one of the authors of Analysis of Capture-Recapture Data (along with Byron Morgan). The book covers the many modern developments of capture-recapture (and related) methods and will be of interest to researchers and graduate students in statistics, ecology and demography. It contains 130 exercises designed to complement and extend the text and help readers to assimilate the material.

Francesca Parrini

Francesca Parrini

Francesca Parrini

“My broad research interests lie in the ecology and behaviour of mammalian herbivores, their interaction with biotic and abiotic factors and the integration of factors governing decisions at the small foraging scale and factors governing decisions at the landscape level. As such, my research lies at the interface of remote sensing, behavioural ecology and conservation. Recently I have become interested in the application of graph theory and network analysis to ecological settings, in particular to study the spatio-temporal structure of animal movement patterns.”

Last year Francesca had her article (co-authored with Maria Miranda) ‘Congruence between species phylogenetic and trophic distinctiveness‘ published in Biodiversity and Conservation. In this paper the authors investigate the relationship between species’ phylogenetic history and patterns of resource use. They show that there is congruence between species phylogenetics and interaction distinctiveness and propose that this relationship could provide a possible novel approach to the conservation of ecosystem diversity.

We are thrilled to welcome Nick, Rachel and Francesca to the Associate Editor Board and we look forward to working with them over the coming years.