The Power of Infinity: Using 3D Fractal Geometry to Study Irregular Organisms

Post provided by Jessica Reichert, André R. Backes, Patrick Schubert and Thomas Wilke

The Problem with the Shape

More than anything else, the phenotype of an organism determines how it interacts with the environment. It’s subject to natural selection, and may help to unravel the underlying evolutionary processes. So shape traits are key elements in many ecological and biological studies.

The growth form of corals is highly variable. ©Jessica Reichert

The growth form of corals is highly variable. ©Jessica Reichert

Commonly, basic parameters like distances, areas, angles, or derived ratios are used to describe and compare the shapes of organisms. These parameters usually work well in organisms with a regular body plan. The shape of irregular organisms – such as many plants, fungi, sponges or corals – is mainly determined by environmental factors and often lacks the distinct landmarks needed for traditional morphometric methods. The application of these methods is problematic and shapes are more often categorised than actually measured.

As scientists though, we favour independent statistical analyses, and there’s an urgent need for reliable shape characterisation based on numerical approaches. So, scientists often determine complexity parameters such as surface/volume ratios, rugosity, or the level of branching. However, these parameters all share the same drawback: they are delineated to a univariate number, taking information from one or few spatial scales and because of this essential information is lost. Continue reading

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Tiny Grains, Big Data: The Global Pollen Project

Post Provided by Andrew Martin

A drawer from the Oxford Long-Term Ecology Lab (OxLEL) pollen reference collections, which has been digitised into the Global Pollen Project reference set.

A drawer from the Oxford Long-Term Ecology Lab (OxLEL) pollen reference collections, which has been digitised into the Global Pollen Project reference set.

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

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

Biggest Library of Bat Sounds Compiled

Below is a press release about the Methods paper ‘Acoustic identification of Mexican bats based on taxonomic and ecological constraints on call design‘ taken from the University College London.

The Funnel-eared bat (Natalus stramineus)

The Funnel-eared bat (Natalus stramineus)

The biggest library of bat sounds has been compiled to detect bats in Mexico – a country which harbours many of the Earth’s species and has one of the highest rates of species extinction and habitat loss.

An international team led by scientists from UCL, University of Cambridge and the Zoological Society of London, developed the reference call library and a new way of classifying calls to accurately and quickly identify and differentiate between bat species.

It is the first time automatic classification for bat calls has been attempted for a large variety of species, most of them previously noted as hard to identify acoustically. Continue reading

Issue 7.3

Issue 7.3 is now online!

The March issue of Methods is now online!

This month’s issue contains two Applications articles and two Open Access articles, all of which are freely available.

METAGEAR: A comprehensive, multifunctional toolbox with capabilities aimed to cover much of the research synthesis taxonomy: from applying a systematic review approach to objectively assemble and screen the literature, to extracting data from studies, and to finally summarize and analyse these data with the statistics of meta-analysis.

Universal FQA Calculator: A free, open-source web-based Floristic Quality Assessment (FQA) Calculator. The calculator offers 30 FQA data bases (with more being added regularly) from across the United States and Canada and has been used to calculate thousands of assessments. Its growing repository for site inventory and transect data is accessible via a REST API and represents a valuable resource for data on the occurrence and abundance of plant species. 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

Biodiversity estimates from DNA sequences

The complexity of new methodologies can present a challenging barrier towards their uptake. Recognising this, Jeff Powell,  author of Accounting for uncertainty in species delineation during the analysis of environmental DNA sequence data, has put together an excellent tutorial to guide people through the implementation of his objective, theory-based method for predicting species boundaries, which explicitly incorporates uncertainty in the classification system into biodiversity estimation.

The tutorial is available to view and download from Slideshare, and the relevant R code can be found as supplementary material on Wiley Online Library.

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