When Measuring Biodiversity, Do Individuals Matter?

Post provided by Samuel RP-J Ross

Close up of a black-capped babbler (Pellorneum capistratum), one of the species included in our study.

Close up of a black-capped babbler (Pellorneum capistratum), one of the species in our study.

Our newly-developed method simulates intraspecific trait variation when measuring biodiversity. This gives us an understanding of how individual variation affects ecosystem processes and functioning. We were able to show that accounting for within-species variation when measuring functional diversity can reveal details about ecological communities which would otherwise remain unseen. Namely, we found a negative impact of selective-logging on birds in Borneo when accounting for intraspecific variation which we could not detect when ignoring intraspecific variation.

Why Biodiversity Matters

Biodiversity is important for many reasons. One of the main reasons is its contribution to the range of goods and services provided by ecosystems (i.e. ecosystem services) that we can take advantage of, such as natural food resources or climatic regulation. It’s generally believed that biodiversity contributes to these services by increasing and maintaining ‘ecosystem functioning’ – often defined as the rate at which ecosystems are turning input energy (e.g. sunlight) into outputs (e.g. plant biomass). Continue reading

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My Entropy ‘Pearl’: Using Turing’s Insight to Find an Optimal Estimator for Shannon Entropy

Post provided by Anne Chao (National Tsing Hua University, Taiwan)

Shannon Entropy

Not quite as precious as my entropy pearl

Not quite as precious as my entropy pearl ©Amboo Who

Ludwig Boltzmann (1844-1906) introduced the modern formula for entropy in statistical mechanics in 1870s. Since its generalization by Claude E. Shannon in his pioneering 1948 paper A Mathematical Theory of Communication, this entropy became known as ‘Shannon entropy’.

Shannon entropy and its exponential have been extensively used to characterize uncertainty, diversity and information-related quantities in ecology, genetics, information theory, computer science and many other fields. Its mathematical expression is given in the figure below.

In the 1950s Shannon entropy was adopted by ecologists as a diversity measure. It’s interpreted as a measure of the uncertainty in the species identity of an individual randomly selected from a community. A higher degree of uncertainty means greater diversity in the community.

Unlike species richness which gives equal weight to all species, or the Gini-Simpson index that gives more weight to individuals of abundant species, Shannon entropy and its exponential (“the effective number of common species” or diversity of order one) are the only standard frequency-sensitive complexity measures that weigh species in proportion to their population abundances. To put it simply: it treats all individuals equally. This is the most natural weighing for many applications. Continue reading

New Associate Editor: Anne Chao

Today, we are pleased to be welcoming a new member of the Methods in Ecology and Evolution Associate Editor Board. Anne Chao joins us from the National Tsing Hua University in Taiwan and you can find out a little more about her below.

Anne Chao

Anne Chao

“I am 60% statistician, 30% mathematician and 10% ecologist. Mathematical and statistical problems in ecology and evolution fascinate me. My current research interests include statistical inferences of biodiversity measures (for example taxonomic, phylogenetic, and functional diversities along with related similarity/differentiation indices), and statistical analysis of ecological and environmental survey data (such as standardising biological samples and rarefaction/extrapolation techniques).”

Anne has been very engaged with the journal over the past few years as a regular reviewer and as an author. Her first article in Methods, Entropy and the species accumulation curve‘ (written with YT Wang and Lou Jost) was published in 2013 and is now freely available. Continue reading

Advances in Phylogenetic Methods – The Applications Papers

Original Image ©PLOS One Phylogeny

Original Image ©PLOS One Phylogeny

Timed to coincide with Evolution 2015, we have released a new Virtual Issue on Phylogenetic Methods. All of the articles in this Virtual Issue will be freely available for a limited period.

On Friday, we gave some more information about the research articles in this Virtual Issue. In this post, we will be focusing on the Applications papers.

Applications papers introduce new tools for research, which provide practitioners with an important source of information and background on the tools they use. In this Virtual Issue we have highlighted the newest Applications papers that describe how phylogenetic methods are contributing to the fields of ecology and evolution. These include tools with aims as diverse as phylogenetic tree reconstruction and analysing phylogenetic diversity in communities. All Applications papers, not just those in the Virtual Issue, are free to access.

You can see a little more information on each of the Applications Papers below.

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Virtual Issue: Advances in Phylogenetic Methods

Original Image ©PLOS One Phylogeny

Original Image ©PLOS One Phylogeny

Timed to coincide with Evolution 2015, we have released a new Virtual Issue on Phylogenetic Methods. All of the articles in this Virtual Issue will be freely available for a limited period.

An understanding of the tree of life contributes to many facets of biology. This Virtual Issue has assembled studies that showcase the breadth of the utility of phylogenetic trees, including phylogenetic beta diversity, trait evolution, diversification, biodiversity studies, phylogenetic signal, biogeography, ecosystem functioning, and host-pathogen dynamics.

The Research papers included are excellent examples of new ways that phylogenies can be applied to central questions in ecology, evolution and biodiversity, such as measuring niche conservatism, trait evolution and diversification rates. The issue also has articles on barcoding methods, which increasingly are used to understand phylogenetic and functional diversity.

You can see a little more information on each of the articles below.

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International Day for Biological Diversity 2015

Happy International Day for Biological Diversity everyone!

As you may know, today (Friday 22 May) is the United Nations Day for Biodiversity and we are celebrating by highlighting some of the best papers that have been published on biodiversity in Methods in Ecology and Evolution. This is by no means an exhaustive list and you can find many more articles on similar topics on the Wiley Online Library (remember, if you are a member of the BES, you can access all Methods articles free of charge).

If you would like to learn more about the International Day for Biological Diversity, you may wish to visit the Convention on Biological Diversity website, follow them on Twitter or check out today’s hashtag: #IBD2015.

Without further ado though, here are a few of the best Methods papers on Biological Diversity:

Methods Cover - August 2012Biodiversity Soup

We begin with an Open Access article from one of our Associate Editors, Douglas Yu (et al.). This article was published in the August issue of 2012 and focuses on the metabarcoding of arthropods. The authors present protocols for the extraction of ecological, taxonomic and phylogenetic information from bulk samples of arthropods. They also demonstrate that metabarcoding allows for the precise estimation of pairwise community dissimilarity (beta diversity) and within-community phylogenetic diversity (alpha diversity), despite the inevitable loss of taxonomic information.

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Issue 6.4: Opportunities at the Interface Between Ecology and Statistics

Issue 6.4 is now online!

© Chun-Huo Chiu and Ching-Wen Cheng

The April issue of Methods, which includes our latest Special Feature: “Opportunities at the Interface Between Ecology and Statistics” is now online!

Opportunities ar the Interface Between Ecology and Statistics is a collection of eight articles which arose from the Eco-Stats Symposium at the University of New South Wales (Australia) in July 2013.This Symposium was designed to be a collaborative forum for researchers with interests in ecology and statistics. It brought together internationally recognised leaders in these two fields (such as Jane Elith, Trevor Hastie, Anne Chao and Shirley Pledger) – many of whom have contributed articles to this Special Feature.

The Eco-Stats Symposium was arranged around five special topics, all of which are represented in this issue of Methods. Those five topics are:

In his Editorial for the Special Feature, Guest Editor David Warton suggests that one of the reasons for the success of Methods in Ecology and Evolution may be that it provides a forum for statisticians and ecologists to interact. The articles in this issue, and the conference that gave rise to them, show that these interactions can provide significant benefits for both groups.

There will be another Eco-Stats Symposium at the University of New South Wales in December of this year (8-10 December, 2015).
For more details on this, please click here.
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