Correlative distribution models have become essential tools in conservation, macroecology and ecology more generally. They help turn limited occurrence records into predictive maps that help us get a better sense of where species might be found, which areas might be critical for their protection, how large their range currently is, and how it might change with climate change, urban encroachment or other forms of habitat conversion.
It can be frustrating, however, when species distribution models (and the predictive maps they produce) don’t adequately capture what we already know about the habitat needs of a species. A major challenge to date has been to represent the environmental needs of species that require distinct habitats during different life stages or behavioural states. Rainbow parrotfish (Scarus guacamaia), for example, spend their youth sheltered from predators in mangrove areas before moving onto coral reefs, and European nightjars (Caprimulgus europaeus) breed in heathland but require access to grazed grassland for foraging. Correlative distribution models confronted with occurrence records from both life stages or behavioural modes tend to produce poor predictive maps because they confound these distinct requirements. Continue reading →
This double-size issue contains six Applications articles (one of which is Open Access) and two Open Access research articles. These eight papers are freely available to everyone, no subscription required.
–Temperature Manipulation: Welshofer et al. present a modified International Tundra Experiment (ITEX) chamber design for year-round outdoor use in warming taller-stature plant communities up to 1.5 m tall.This design is a valuable tool for examining the effects of in situ warming on understudied taller-stature plant communities
–Zoon: The disjointed nature of the current species distribution modelling (SDM) research environment hinders evaluation of new methods, synthesis of current knowledge and the dissemination of new methods to SDM users. The zoon R package aims to overcome these problems by providing a modular framework for constructing reproducible SDM workflows.
–BEIN R Package: The Botanical Information and Ecology Network (BIEN) database comprises an unprecedented wealth of cleaned and standardised botanical data. The bien r package allows users to access the multiple types of data in the BIEN database. This represents a significant achievement in biological data integration, cleaning and standardisation.
The climate is changing throughout the globe with consequences for the biogeochemical processes and ecological relationships that drive ecosystems. Scientists have been conducting manipulative experiments to determine the effect of climate warming on ecosystems for several decades. These experiments allow us to observe ecosystem responses before the climate changes occur and have yielded invaluable insight that has expanded our understanding of the natural world.
There is a wide range of creative approaches to mimicking climate warming that have been used, for example open-topped chambers which passively heat small areas of soil and small stature plants (like the ITEX global network), burying heating cables in the soil to directly increase soil temperatures (e.g. Harvard Forest experiments), infrared heating lamps (like Jasper Ridge), or even large scale chambers that can encompass taller stature plants like trees and actively warm the air (like the SPRUCE experiment). The focus of much of these inquiries has been on changes that occur during the growing season, when biological activity is at its peak. Continue reading →
Today we are welcoming two more Associate Editors to the Methods in Ecology and Evolutionwho were invited to work with the journal following our open call earlier this year.Jessica Royles joins from the University of Cambridge, UK and Simon Blomberg is coming to us from the University of Queensland, Australia. You can find out more about both of them below.
“I am a statistician who started out as a lizard demographer. I am interested in all applications of statistics in evolutionary biology and systematics. It is my passion to see that good science gets done by everybody, and sound statistical methods are essential to reach that goal. My research involves the application of stochastic process models (predominantly Itoh diffusions) to the macroevolution of quantitative traits. I believe that evolution can be described by beautiful mathematics but theory must be tested with data. I have published widely on phylogenetic comparative methods. I use Bayesian methods, data augmentation, regularisation and other modern and traditional statistical methods. I am interested in how to treat missing data. I still like lizards. Also jazz.”
“I am interested in the impact of climate change on plant physiology and specialise in using stable isotopes as environmental markers. Having worked in Antarctica I have strong interests in polar biology, high latitude peatlands and fieldwork techniques. My current work focusses on temperate bryophytes and I am interested in using techniques including gas exchange and chlorophyll fluorescence at different spatial scales to link the leaf level to the ecosystem level.”
This double-sized issue contains three Applications articles and two Open Access articles. These five papers are freely available to everyone, no subscription required.
–Phylogenetic Trees: The fields of phylogenetic tree and network inference have advanced independently, with only a few attempts to bridge them. Schliep et al. provide a framework, implemented in R, to transfer information between trees and networks.
–Emon: Studies, surveys and monitoring are often costly, so small investments in preliminary data collection and systematic planning of these activities can help to make best use of resources. To meet recognised needs for accessible tools to plan some aspects of studies, surveys and monitoring, Barry et al. developed the R package emon, which includes routines for study design through power analysis and feature detection.
–Haplostrips: A tool to visualise polymorphisms of a given region of the genome in the form of independently clustered and sorted haplotypes. Haplostrips is a command-line tool written in Python and R, that uses variant call format files as input and generates a heatmap view.
When trying to understand how wildlife, for example a bird species, may react to climate change scientists generally study how species numbers vary in relation to climatic or weather variables (e.g. Renwick et al. 2012, Johnston et al. 2013). The way this tends to be done is by gathering information (data!) about bird numbers as well as the weather variables (for example temperature) in several locations (i.e. in space) and fitting a regression model to these data to detect and illustrate how bird numbers go up or down with temperature.
Data on bird numbers and temperatures in several locations lets researchers see the relationship between the two.
This relationship is then used to forecast how bird numbers may change along with potential temperature changes in the future (i.e. in time), for example due to climate change.
Relationships between bird numbers and temperature in a given location are often used to forecast changes in bird numbers with expected changes in temperatures over time.
Britain’s smallest bird species, the goldcrest, is being hit hard by cold winters, new analysis methods developed by researchers at the University of St Andrews have revealed.
The data analysis techniques, published today in Methods in Ecology and Evolution, take a longer term view over multiple locations and for a period of several years, compared to previous studies.
They showed that the cold temperatures strongly affected breeding numbers of the goldcrest, while in contrast, the song thrush was not affected by the cold, but benefited from wet and mild summers. Continue reading →
The Global Pollen Project is a new, online, freely available tool developed to help people identify and disseminate palynological resources. Palynology – the study of pollen grains and other spores – is used across many fields of study modern and fossil vegetation dynamics, forensic sciences, pollination, beekeeping, and much more. This platform helps to facilitate cross/multi-disciplinary integration and discussion, outsourcing identifications, expertise and the sharing of knowledge.
Pollen’s Role in Plant Conservation
Successful conservation of rare, threatened, and valuable plants is dependent on an understanding of the threats that they face. Also, conservationists must prioritise species and populations based on their value to humans, which may be cultural, economic, medicinal, etc. The study of fossil pollen (palaeoecology), deposited through time in sediments from lakes and bogs, can help inform the debate over which species to prioritise: which are native, and when did they arrive? How did humans impact species richness? By establishing such biodiversity baselines, policymakers can make more informed value judgements over which habitats and species to conserve, especially where conservation efforts are weighted in favour of native and/or endemic flora. Continue reading →
Understanding how biodiversity is distributed and its relationship with the environment is crucial for conservation assessment. It also helps us to predict impacts of environmental changes and design appropriate management plans. Biodiversity across a network of local sites is typically described using three components:
alpha (α) diversity, the average number of species in each specific site of the study area
beta (β) diversity, the difference in species composition between sites
gamma (γ) diversity, the total number of species in the study area.
Despite the many insights provided by the combination of alpha, beta and gamma diversity, the ability to describe species turnover has been limited by the fact that they do not consider more than two sites at a time. For more than two sites, the average beta diversity is typically used (multi-site measures have also been developed, but suffer shortcomings, including difficulties of interpretation). This makes it difficult for researchers to determine the likely environmental drivers of species turnover.
We have developed a new method that combines two pre-existing advances, zeta diversity and generalised dissimilarity modelling (both explained below). Our method allows the differences in the contributions of rare versus common species to be modelled to better understand what drives biodiversity responses to environmental gradients. Continue reading →
Rachel Carson (1940) Fish & Wildlife Service employee photo.
I can’t think of a more inspirational and influential ecologist than Rachel Carson. Nearly fifty years ago she released a book called Silent Spring, which argued that pesticides such as DDT were cascading up through food chains causing the death or sterilisation of birds and other animals. The publication of her book provoked public debate, likely in part because it was serialised in The New Yorker, and led to a paradigm shift in US and (arguably) global pest control policy.
With the full support of the scientific community to verify her facts and arguments, she was able to defeat the chemical industry’s backlash and galvanise public opinion in her favour. The 2005 Stockholm Convention, in which DDT was banned from agricultural use, would likely have never happened if it were not for her work.
“In a post-truth world where trust in the scientific process is being eroded almost daily, Rachel Carson is a perfect example of how we can speak out and be heard while still being scientists.”