Morphoscape Ecology: Assessing The Variability Of Beetle Forms Across Habitats

At the time of George Perkins Marsh’s book ā€˜Man and Natureā€™, published in 1864, people realized that human activities have an impact on the environment. Since then, ecologists developed new metrics to assess such impacts, in order to understand the changes happening in the field and develop preventive or curative measures.

Most of the metrics to assess anthropogenic impacts used, and still use, features of living communities, such as species richness. More recently, however, ecologists also began focusing on species quality by measuring the diversity of evolutionary lineages within habitats and regions, as well as functional traits of particular ecological importance (e.g., body mass, type of locomotion, specializations of the feeding apparatus etc.). These metrics are commonly used by governmental agencies in different countries when monitoring the quality of the environment and are at the basis of political decisions for environmental regulators.

The general idea is that any impact on an ecosystem will impair some aspect of its communities of organisms, for example by reducing the number of species with local extinctions. Among the best-known cases, in streams and rivers, human-induced eutrophication from nearby farms will increase consumption of oxygen and thus cause a reduction in the presence of those species that have high oxygen demands; similarly, in lakes, the release of planktivorous fish for sport fishing will completely change the size spectra of zooplankton, with a reduction of larger crustaceans; indeed, the list of examples of differential response, depending on ecological features, is long and rather well studied.

Yet, one aspect that is not usually considered in such assessments is related to morphological variability at the community level. An ecological community is a group of species living in a certain geographical region or habitat. As anticipated, communities vary in composition, as well as in the functions of their members. However, they can also differ in the number of types of organismal forms that live in those communities. Thus, we wondered whether, as for species abundance and richness, we might expect fewer differences in size or shape across a group of related organisms in strongly anthropized habitats. In this context, each habitat, or area within a larger region, might be seen as a landscape made of different combinations of morphologies, which, together, make up the local ‘morphoscape’. In fact, the ‘morphoscape’ concept has been previously used, within a single species, in paleontology, but no one has explored its usefulness in ecology to assess the morphological complexity of a community.

In our study, we focused on a widespread and diverse family of beetles, the Carabidae (Fig. 1), and measured how big their morphoscape is across four types of habitats (cropland, meadow, poplar stand, and woodland) found in the Padana Plain of northern Italy. Using museum specimens, and available information on species composition, we selected a single adult male individual for each species found in the four habitats and applied a method of image analysis to quantify body size and body shape using digital photos. Within a habitat, the magnitude of the morphoscape was quantified using different metrics. The most intuitive of these is simply the range of variation, which is analogous to computing the difference between the tallest and shortest person in a group of people to estimate how much individuals differ in that sample.

We discovered that body size partly mirrored differences in species richness, with more variation in the habitat with more species, regardless of human impact. Thus, open habitats, such as meadow and cropland, housed a wide range of body sizes, as well as more species of carabid beetles (respectively ca. 100-110), despite being under stronger anthropogenic pressures. However, woodland, the least impacted habitat, had about as much size variation across species as cropland and meadow, and consistently showed the biggest morphoscape for shape (Fig. 2). This is particularly remarkable if one considers that cropland, in fact, had a morphoscape almost as big as woodland, but woodland reached that magnitude despite being host to almost 20% fewer species than cropland. This suggests that even if a relatively pristine closed woodland habitat could be less species-rich, it might, in fact, conceal a relatively higher number of morphologies and be thus potentially richer in the ecological functions played by its fewer but more disparate members. Using an analogy, it is like having two companies, that we call C and W, renting vehicles for different types of work: both companies have a full range of sizes going from small bikes to big trucks; C has more brands; however, W can offer some less common types of vehicles, for instance, auto-rickshaws and caravans, that are not available at C.

Fig. 2. Configuration of anatomical landmarks used to describe Carabid beetle body form (left) and a bar chart (right) of mean shape variability showing a bigger morphoscape for woodland compared to the other three Padana plain habitats. (Andrea Cardini)

That the biggest morphoscape for carabid body shape in the Padana Plain occurs in the least anthropized habitat raises some intriguing questions. Shape, a highly multivariate and complex trait, often indicative of adaptations, might be informative on both genetic and ecological variability, including some of the ecological functions that might be impacted by human activities. In fact, however, although form and function often correlate, which is what allows anatomists to predict the ecology and behavior of extinct animals such as dinosaurs, for now, we cannot be sure that more disparate shapes necessarily correspond to ecologically more complex habitats. Future studies using similar approaches in beetles from other regions, as well as in other groups of organisms, will be needed to find robust answers. Excitingly, the future might also bring some interesting parallels with other less conventional ecological disciplines, such as sound ecology, in which there is a growing body of evidence showing that healthy ecosystems might indeed have more complex acoustic landscapes or soundscapes.

These findings are described in the article entitled Estimating the magnitude of morphoscapes: how to measure the morphological component of biodiversity in relation to habitats using geometric morphometrics, published in the journal The Science of Nature.

This work was led by Diego Fontaneto (National Research Council of Italy), Martina Panisi (Faculdade de CiĆŖncias da Universidade de Lisboa), Mauro Mandrioli (University of Modena and Reggio Emilia), Dario Montardi (University of Modena and Reggio Emilia), Maurizio Pavesi (Museo Civico di Storia Naturale), and Andrea Cardini (UniversitĆ  di Modena e Reggio Emilia).

About The Author

Andrea Cardini

I am a biologist specialized in the study of form variation in mammals, and other organisms. I use computerized methods of image analysis to answer scientific questions related to group differences, and the factors that might produce them, in evolution, taxonomy and biogeography, palaeontology, biomedicine and forensics.

I am also interested in learning, and helping to develop, landmark-based methods of size and shape analysis. This interest has led me to co-organize and teach in more than 20 international workshops on shape analysis in Europe, the Middle East and South America.

I am a full time permanent Researcher at the University of Modena & Reggio Emilia and an Adjunct Associate Professor at The University of Western Australia.

Diego Fontaneto

Diego Fontaneto currently works at the Water Research Institute (IRSA) of the National Research Council of Italy (CNR) in Verbania Pallanza, Italy.

Mauro Mandrioli

My research interests are mainly focussed on the study of insect genomes and chromosomes with particular interest for insects of agricultural interest, such as aphids. I'm also interested in the identification and study of of immunity-related genes in insect-symbiont interactions, the analysis of the distribution of symbiotic bacteria in insect tissues and the development of primary in vitro insect cell culture.

Martina Panisi

Martina is affiliated with the University of Lisbon, Center for Environmental Biology.

Speak Your Mind!

READ THIS NEXT

Fighting Atrial Fibrillation With Ice: Cryoballoon Ablation Best Practices Set Standards As Usage Expands

Atrial fibrillation, or AFib, is the most common heart rhythm abnormality. AFib occurs when the top chambers of the heart quiver or ā€œfibrillateā€ instead of beating normally, often resulting in a very fast heart rate. A patient with AFib may feel heart palpitations, shortness of breath, and/or dizziness. Episodes of AFib can come and go […]

How Science Helped Detect The Powerful Explosive TATP In Unidentified Objects

Triacetone triperoxide (TATP) is a powerful explosive without military use because it is very sensitive to mechanical shock and so very difficult to safely handling, a reason for which terrorists dubbed TATP ā€œthe Mother of Satanā€. TATP is easily prepared from acetone and hydrogen peroxide under acidic catalysis, being a home-made explosive almost undetectable by […]

Shape Deformable Hydrogels

Imagine what functions can be performed with a soft, flexible but tough transformer that can change its shape upon external stimuli? Hydrogels are three-dimensionally cross-linked polymeric networks that can absorb a large amount of water while maintaining their solid-like shapes. They are typically soft and wet materials. Some smart hydrogels can change their geometric shapes […]

Antelope Canyon: Famous Slot Canyon In Arizona

Antelope Canyon is a slot canyon formed by erosion found on the land of the Navajo nation, just east of Page, Arizona. Antelope Canyon is actually divided into two separate slot canyons, but the whole region is collectively referred to as Antelope Canyon. The upper part of the canyon is usually referred to as The […]

Liquid Metal Activated Al-Water Reaction: A New Approach Leading To “Hy-Time”

When it comes to hydrogen production, people think of the electrolysis or photolysis of water. However, in these processes, the energy efficiency stays low, and the production capacity could be significantly enhanced. Among the many technological strategies ever tried, the Al-H2O reaction is a rather favored way to produce hydrogen, although it is always hindered […]

Applying Simple Techniques To Develop Smarter Green Roof Substrates

Urban sprawl and dense urbanization are creating problems with how we manage our stormwater. Ā Large areas of impermeable surfaces (i.e. paved roadways, paths, buildings, and loss of green spaces) combined with more intense and frequent storms that are expected to occur in the coming decades, has forced city developers and landscape architects to seek new […]

Research Says Trump Administration’s Focus On Video Game Violence Is Misguided

This Thursday saw President Donald Trump meet with members of video games industry to discuss a proposed link between violent video games and violent killings, such as the Valentineā€™s Day shooting which occurred at a high school in Broward County, Florida. A Meeting With The Entertainment Software Association The shootings which occurred in Florida kicked […]