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

Capturing the Contribution of Rare and Common Species to Turnover: A Multi-Site Version of Generalised Dissimilarity Modelling

Post provided by Guillaume Latombe and Melodie A. McGeoch

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:

  1. alpha (α) diversity, the average number of species in each specific site of the study area
  2. beta (β) diversity, the difference in species composition between sites
  3. gamma (γ) diversity, the total number of species in the study area.
Two tawny frogmouths, a species native to Australia. ©Marie Henriksen.

Two tawny frogmouths, a species native to Australia. ©Marie Henriksen.

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

Decoupling Functional and Phylogenetic Dissimilarity between Organisms

Francesco de Bello describes the main elements of the method he has recently published in Methods in Ecology and Evolution. The method aims at decoupling and combining functional trait and phylogenetic dissimilarities between organisms. This allows for a more effective combination of non-overlapping information between phylogeny and functional traits. Decoupling trait and phylogenetic information can also uncover otherwise hidden signals underlying species coexistence and turnover, by revealing the importance of functional differentiation between phylogenetically related species.

In the video Francesco visually represents what the authors think their tool is doing with the data so you can see its potential. This method can provide an avenue for connecting macro-evolutionary and local factors affecting coexistence and for understanding how complex species differences affect multiple ecosystem functions.

This video is based on the article ‘Decoupling phylogenetic and functional diversity to reveal hidden signals in community assembly‘ by de Bello et al.

 

New Associate Editors

Today we are welcoming two new people to the Methods in Ecology and Evolution Associate Editor Board. Pierre Durand is joining us from the University of the Witwatersrand (South Africa) and Andrew Mahon joins from Central Michigan University (USA). You can find out more about Pierre and Andrew below.

Pierre Durand

Pierre Durand

“My research is broadly focussed on the evolution of complexity. Many of my projects are related to the evolutionary ecology of programmed cell death (PCD) in unicellular organisms; how PCD impacts microbial communities; and how the philosophy of levels of selection informs our understanding of PCD evolution. I have also examined other aspects of complexity evolution such as the origin of life and group formation in unicellular chlorophytes in response to predation. The model organisms I typically use are phytoplankton. With specific reference to submissions to Methods in Ecology and Evolution, I have used a range of methods in my research, including general cell and molecular biology tools, biochemical assays, microscopy, flow cytometry, bioinformatics and computational algorithms.”

The most current projects in Pierre’s laboratory concern: programmed cell death evolution and complexity in microbial communities; changes in phytoplankton abundance and diversity in harmful algal blooms, led by PhD candidate Andrew Ndhlovu (“A red tide forming dinoflagellate Prorocentrum triestinum: identification, phylogeny and impacts on St Helena Bay, South Africa” in review in Phycologia); and the genomics of the four-celled chlorophyte Tetrabaena socialis, led by PhD candidate Jonathan Featherson.

Andrew Mahon

Andrew Mahon

“I’m a molecular ecologist who uses genetic and genomic tools to ask questions ranging from surveillance and monitoring to biodiversity and phylogeography.  My work includes development of novel molecular detection tools and metabarcoding applications for aquatic invasive species.  I’m also interested in applying molecular tools to ask questions related to the evolution and biodiversity of benthic marine invertebrates in Antarctica.”

Andrew has recently been published in the journal Research Ideas and Outcomes (‘DNAqua-Net: Developing new genetic tools for bioassessment and monitoring of aquatic ecosystems in Europe‘) and in Environmental Science and Technology (‘Influence of Stream Bottom Substrate on Retention and Transport of Vertebrate Environmental DNA‘). He also has a manuscript in press with Ecology and Evolution (‘Geographic structure in the Southern Ocean circumpolar brittle star Ophionotus victoriae (Ophiuridae) revealed from mtDNA and single-nucleotide polymorphism data‘).

We are thrilled to welcome Pierre and Andrew to the Associate Editor Board and we look forward to working with them over the coming years.

Progressive Change BACIPS: Estimating the Effects of Environmental Impacts over Time

Post provided by Lauric Thiault

BACIPS (Before-After Control-Impact Paired Series) is probably the best-known and most powerful approach to detect and quantify human interventions on ecosystems. In BACIPS designs, Impact and Control sites are sampled simultaneously (or nearly so) multiple times Before and After an intervention. For each sampling survey conducted Before or After, the difference in the sampled response variable (e.g. density) is calculated. Before and After differences are then compared to provide a measure of the effect of the intervention, assuming that the magnitude of the induced change is constant through time. However, many interventions may not cause immediate, constant changes to a system.

We developed a new statistical approach – called Progressive-Change BACIPS (Before-After Control-Impact Paired-Series) – that extends and generalises the scope of BACIPS analyses to time-dependent effects. After quantifying the statistical power and accuracy of the method with simulated data sets, we used marine and terrestrial case studies to illustrate and validate their approach. We found that the Progressive-Change BACIPS works pretty well to estimate the effects of environmental impacts and the time-scales over which they operate.

The following images show the diversity of contexts in which this approach can be undertaken.

To find out more about Progressive Change BACIPS, read our Methods in Ecology and Evolution article ‘Progressive-Change BACIPS: a flexible approach for environmental impact assessment’.

The Field Guide to Sequence-Based Identification of Biodiversity: An Interview with Simon Creer

In a new Methods in Ecology and Evolution podcast, Georgina Brennan (Bangor University) interviews Simon Creer (Bangor University) about his article ‘The ecologist’s field guide to sequence-based identification of biodiversity‘. They talk about about where the idea for the paper came from, what it’s aim are and who will benefit from it. We hear how new sequences can improve and enhance current biomonitoring programmes (and make them quicker and cheaper).

To find out more about Sequence-based Identification of Biodiversity, read the Open Access Methods in Ecology and Evolution article ‘The ecologist’s field guide to sequence-based identification of biodiversity‘.

 

Lichens and the “health” of ecosystems: we are closer to a global ecological indicator

Below is a press release about the Methods paper ‘Tracking global change using lichen diversity: towards a global-scale ecological indicator‘ taken from the University of Lisbon.

Candelaria pacifica. © Paula Matos

Candelaria pacifica. © Paula Matos

For the first time, it is possible to integrate at the global scale the results obtained with the most widely used methods to evaluate the “health” of ecosystems using lichens. This is the result of a study now published in the journal Methods in Ecology and Evolution, and represents a fundamental step for this indicator to be considered at the global scale and included in the list of indicators of the United Nations.

Lichens have long been successfully used by scientists as ecological indicators – a kind of environment health thermometer. These complex organisms – the yellow or green taints we often see on the surface of tree trunks – are very sensitive to pollution and changes in temperature and humidity. Evaluating how many lichens, of what kind, and their abundance in a certain ecosystem allows scientists to understand the impact that problems like climate change or pollution have on those ecosystems.  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

Conifers for Christmas: Evolution above the level of species

Post provided by  Aelys Humphreys

Conifers for Christmas

It’s somehow fitting that the centre piece of an ancient midwinter tradition in Europe – that of decorating and worshipping an evergreen tree – is an ancient seed plant, a conifer. In Europe, we tend to think of conifers as “Christmas trees” – evergreen trees with needles and dry cones, restricted to cold and dry environments – but conifers are much more diverse and widespread than that. There are broad-leaved, tropical conifers with fleshy cones and even a parasitic species that is thought to parasitise on members of its own family!

Conifer diversity. Classic Christmas tree style conifers in the snow; a broadleaved, tropical podocarp (© Ming-I Weng); the only parasitic gymnosperm, Parasitaxus usta (©W. Baker).

Conifer diversity. Classic Christmas tree style conifers in the snow; a broadleaved, tropical podocarp (© Ming-I Weng); the only parasitic gymnosperm, Parasitaxus usta (©W. Baker).

However, while today’s distribution of conifers is global – spanning tropical, temperate and boreal zones – it is fragmented. The conifer fossil record extends well into the Carboniferous and bears witness to a lineage that was once much more abundant, widespread and diverse. So we can tell that today’s diversity and distribution have been shaped by hundreds of millions of years of speciation, extinction and migration. Continue reading

Can We Really Measure Habitat Condition From Space?

Post provided by Tom Harwood, Randall Donohue, Simon Ferrier, Tim McVicar, Graeme Newell, Matt White and Kristen Williams

Remotely sensing can see patterns of land cover, but how do we use this information to quantify human impact on biodiversity?

Remotely sensing can see patterns of land cover, but how do we use this information to quantify human impact on biodiversity? ©NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team

It’s very hard to make sensible choices without sensible information. When it comes to actions around changing land use and its ecological impact though, this is often what we are forced to do. If we want to reduce the impact of human activities on natural ecosystems, we need to know how much change has already occurred and how altered an ecosystem might be from its “natural” state.

Working out which parts of the landscape have been changed and mapping the absence of natural vegetation is an achievable (though onerous) task. However, moving beyond this binary view of the world is a huge challenge. Pretty much all habitat has been modified by human influences to some extent – by, for example, wood extraction, the introduction of invasive species or livestock grazing. This means that a lot of the apparently native habitat is no longer capable of supporting its full complement of native biodiversity. Continue reading