Editor Recommendation – HistMapR: Rapid Digitization of Historical Land-Use Maps in R

Post provided by Sarah Goslee

For an ecologist interested in long-term dynamics, one of the most thrilling experiences is discovering a legacy dataset stashed away somewhere.

For an ecologist interested in long-term dynamics, one of the most daunting experiences is figuring how to turn that box full of paper into usable data.

The new tool HistMapR, described in ’HistMapR: Rapid digitization of historical land-use maps in R’ by Alistair Auffret and colleagues, makes one part of that task much easier.

Examples of input (©Lantmäteriet) and output maps from (a–b) the District Economic map and (c–d) the Economic map.

Examples of input (©Lantmäteriet) and output maps from (a–b) the District Economic map and (c–d) the Economic map.

Historical maps with coloured areas denoting different land cover or use are a valuable record, but difficult to analyse. This R package automates much of the time-consuming and tedious process of turning paper maps into classified categorical raster maps.

A map is scanned, imported into R, and the software is trained by clicking in different areas of each category. It then automatically classifies pixels based on which colour they are most similar to. The resulting classification is assessed manually. The process can be repeated with slightly different parameters until a good fit is achieved.

The authors found 80-90% agreement between HistMapR classification and manual digitisation (sources of error included clarity of original maps and scan quality). Using HistMapR reduced the time needed for digitising a series of historical land cover maps from two months to two days. Ecologists interested in long-term dynamics should be cheering!

The HistMapR package is available on GitHub and you can find example scripts on Figshare, so you can get right to work.

HistMapR: Rapid digitization of historical land-use maps in R‘ by Auffret et al. is a freely available Applications article (no subscription required).

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Building Universal PCR Primers for Aquatic Ecosystem Assessments

Post provided by Vasco Elbrecht

Many things can negatively affect stream ecosystems – water abstraction, eutrophication and fine sediment influx are just a few. However, only intact freshwater ecosystems can sustainably deliver the ecosystem services – such as particle filtration, food biomass production and the supply of drinking water – that we rely on. Because of this, stream management and restoration has often been in the focus of environmental legislation world-wide. Macrozoobenthic communities are often key biological components of stream ecosystems. As many taxa within these communities are sensitive to negative stressors introduced by humans, they’re ideal for assessing the quality of water.

Unfortunately, most macrozoobenthic taxa – such as stone-, may-, and caddisflies as well as most other invertebrates – are often found in juvenile larval life stages in these ecosystems, so they’re often difficult to identify based on morphology. With the DNA based metabarcoding method though, almost all taxa in a stream can be reliably identified up to species level using a standardised gene fragment. One key component of this strategy is the development of universal markers, which allow detection of the diverse macrozoobenthic groups.

Our new R package PrimerMiner provides a framework for obtaining sequence data from available reference databases and identifying suitable primer binding sites for marker amplification. The package makes this process quicker and easier. In the following pictures, we summarise the key steps of DNA metabarcoding.

To find out more about PrimerMiner, read our Methods in Ecology and Evolution article ‘PrimerMiner: an r package for development and in silico validation of DNA metabarcoding primers’. Like all Applications articles, this paper is freely available to everyone.

Digitizing Historical Land-use Maps with HistMapR

Habitat destruction and degradation represent serious threats to biodiversity, and quantification of land-use change over time is important for understanding the consequences of these changes to organisms and ecosystem service provision.

Historical land-use maps are important for documenting how habitat cover has changed over time, but digitizing these maps is a time consuming process. HistMapR is an R package designed to speed up the digitization process, and in this video we take an example map to show you how the method works.

Digitization is fast, and agreement with manually digitized maps of around 80–90% meets common targets for image classification. We hope that the ability to quickly classify large areas of historical land use will promote the inclusion of land-use change into analyses of biodiversity, species distributions and ecosystem services.

This video is based on the Applications article ‘HistMapR: Rapid digitization of historical land-use maps in R‘ by Auffret et al. This article is freely available to anyone (no subscription required).

The package is hosted on GitHub and example scripts can be downloaded from Figshare.

piecewiseSEM: Exploring Nature’s Complexity through Statistics

Post provided by Jonathan S. Lefcheck

Nature is complicated. As a scientist, you might say, “Well, duh,” but as students of nature, this complexity is probably the single greatest challenge we must face in trying to dissect the hows and whys of the natural world.

History is a Set of Lies Agreed Upon: Moving beyond ANOVA

For a long time, we tried to strip this complexity away by conducting very controlled experiments adhering to rigid designs. The ‘two-way fully-crossed analysis of variance’ will be familiar to anyone who has taken even the most basic stats class, because, for many decades, it was the gold standard for any experiment.

It might be tough to manipulate this whole reef.

The problem is: the real world doesn’t adhere to an ANOVA design. By this, I mean that by their very nature, manipulative experiments are artificial. It’s hard—if not impossible—to manipulate an entire forest or a coral reef, and as such, we retreat to more tractable, smaller investigations. There is certainly a lot of value in determining whether the phenomenon can occur, but these tightly regulated designs say nothing about whether they are likely to occur, particularly at the scales most relevant to humanity.

To get at the latter point, we must leave the safety of the greenhouse. However, our trusty ANOVA toolbox isn’t very useful anymore, because real-world data often violate the most basic statistical assumptions, not to mention the presence of numerous additional influences that may drive spurious relationships. Continue reading

Biogeography Virtual Issue

Photo © An-Yi Cheng

© An-Yi Cheng

To coincide with the International Biogeography Society’s 2017 conference in Tuscon, Arizona, we have compiled a Virtual Issue that shows off new Methods in Ecology and Evolution articles in the field from a diverse array of authors.

To truly understand how species’ distributions vary through space and time, biogeographers often have to make use of analytical techniques from a wide array of disciplines. As such, these papers cover advances in fields such as evolutionary analysis, biodiversity definitions, species distribution modelling, remote sensing and more. They also reflect the growing understanding that biogeography can include experiments and highlight the increasing number of software packages focused towards biogeography.

This Virtual Issue was compiled by Methods in Ecology and Evolution Associate Editors Pedro Peres-Neto and Will Pearse (both of whom are involved in the conference). All of the articles in this Virtual Issue are free for a limited time and we have a little bit more information about each of the papers included here: Continue reading

moveHMM: An Interview with Théo Michelot

David Warton (University of New South Wales) interviews Théo Michelot (University of Sheffield) about an article on his recent R package moveHMM in Methods in Ecology and Evolution. David and Théo also discuss the case study in the paper – on the understudied wild haggis – and what advances could be made to the package in future.

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rotl Paper Published

THIS PIECE WAS ORIGINALLY POSTED ON THE ROPENSCI BLOG.

We (Francois MichonneauJoseph Brown and David Winter) are excited to announce a paper describing rotl, our package for the Open Tree of Life data, has been published. The full citation is:

Michonneau, F., Brown, J. W., Winter, D. J. (2016), rotl: an R package to interact with the Open Tree of Life data. Methods in Ecology and Evolution. doi: 10.1111/2041-210X.12593

The paper, which is freely available, describes the package and the data it wraps in detail. Rather than rehash the information here, we will use this post to briefly introduce the goals of the package and thank some of the people that helped it come to be.

What Data Does Open Tree Have and How Can rotl Help You Get It?

The Open Tree of Life combines knowledge from thousands of scientific studies to produce a single source of information about the relationships among all species on earth. In addition to storing the trees and taxonomies that go into this project, the Open Tree provides a “synthesis tree” that represents this combined knowledge. The Open Tree data can be accessed via the web page linked above, and through an API. rotl takes advantage of this API to give R users the ability to search for phylogenetic information and import the results into their R sessions. The imported data can then be used with the growing ecosystem of packages for phylogenetic and comparative biology in R. Continue reading

Issue 7.6: Methods in Ecology and Evolution 5th Anniversary Special Feature

Issue 7.6 is now online!

The June issue of Methods, which includes our latest Special Feature – “5th Anniversary of Methods in Ecology and Evolution” – is now online!

Our 5th Anniversary Special Feature is a collection of six articles (plus an Editorial from Executive Editor Rob Freckleton) that highlights the breadth and depth of topics covered by the journal so far. It grew out of our 5th Anniversary Symposium – a joint event held in London, UK and Calgary, Canada and live-streamed around the world in April 2015 – and contains papers by Associate Editors, a former Robert May prize winner and regular contributors to the journal.

The six articles are based on talks given at last May’s Symposium. They focus on:

In his Editorial for the Special Feature, Rob Freckleton looks to the future. In his words: “we hope to continue to publish a wide range of papers on as diverse a range of topics as possible, exemplified by the diversity of the papers in this feature”.

All of the articles in the Special Feature will be freely available for a limited time. In addition to this, two of the articles (Shedding light on the ‘dark side’ of phylogenetic comparative methods and Perturbation analysis of transient population dynamics using matrix projection models) are Open Access.
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RPANDA: A Time Machine for Evolutionary Biologists

Post provided by HÉLÈNE MORLON

Yesterday saw the start of this year’s annual Evolution meeting and to celebrate Hélène Morlon has written a blog post discussing the amazingly versatile RPANDA package that she is developing with her research group. A description of RPANDA was published in the journal earlier this year and, like all our Applications papers, is freely available to read in full.

If you are attending Evolution, as well as attending the fabulous talks mentioned by Hélène below, do stop by booth 125 to see our BES colleague Simon Hoggart. Simon is the Assistant Editor of Journal of Animal Ecology and would be happy to answer your questions about any of our journals or any of the other work we do here at the BES.

RPANDA: a time machine for evolutionary biologists

Imagine “Doc”, Marty’s friend in Back to the Future, trying to travel back millions of years in an attempt to understand the history of life. Instead of building a time machine from a DeLorean sports car powered by plutonium, he could dig fossils, or more likely, he would use molecular phylogenies.

Molecular phylogenies are family trees of species that can be built from data collected today: the genes (molecules) of present-day species (Fig 1). They are often thought of as trees, in reference to Darwin’s tree of life. The leaves represent the present: species that can be found on Earth today. The branches represent the past: ancestral species, which from time to time split, giving rise to two independent species. The structure of the tree tells us which species descend from which ancestors, and when their divergence happened.

birds_phylog

Fig 1: The phylogenetic tree of all birds (adapted from Jetz et al. 2012). Each bird order is represented by a single bird silloutter and a specific colour (the most abundant order of Passeriformes, for example is represented in dark orange). Each terminal leaf represents a present-day bird species, while internal branches represent the evolutionary relationships among these species.

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New Associate Editor: Will Pearse

Today, we are pleased to be welcoming a new member of the Methods in Ecology and Evolution Associate Editor Board. Will Pearse joins us from McGill University in Canada and you can find out a little more about him below.

Will Pearse

“I am an evolutionary ecologist and use phylogeny to link the evolution of species’ traits with their ecological community assembly. I’m interested in phylogenetic methods, macro-evolution of species’ traits, community assembly and developing new statistical tools for all of the above.”

Will is a former winner of the Robert May Early Career Researcher Award. He won the prize in 2013 for his Applications article ‘phyloGenerator: an automated phylogeny generation tool for ecologists‘ (co-authored with Andy Purvis). phyloGenerator is an open-source, stand-alone Python program, that makes use of pre-existing sequence data and taxonomic information to largely automate the estimation of phylogenies. He has also recently had a paper on a R package that allows for measurement, modelling and simulation of phylogenetic structure in ecological data published in Bioinformatics. The article, ‘pez: phylogenetics for the environmental sciences‘, was co-authored with Marc CadotteJeannine Cavender-BaresAnthony IvesCaroline TuckerSteve Walker and Matthew Helmus.

We are thrilled to welcome Will as a new Associate Editor and we look forward to working with him on the journal.