INSECT BIOMES: COMPOSITION, DIVERSITY AND ECOLOGY

Taxonomic and biological composition

IBA will describe the insect faunas of Sweden and Madagascar through a combination of novel molecular methods, high throughput sequencing and bioinformatics applied to 8000 insect community samples collected over a 12-month period. This complete characterization of the Swedish and Malagasy insect fauna will allow us to address a wide range of questions concerning the taxonomic and biological composition of insect biomes that remain largely unresolved from previous studies. For instance, what proportion of species are beetles (Coleoptera); wasps, ants or bees (Hymenoptera); flies, mosquitoes or gnats (Diptera); or butterflies and moths (Lepidoptera)? How much do those proportions vary between ecosystems? How much do they vary between temperate regions and the tropics? How many decomposers are there compared to herbivores? How many parasitoids are there in different communities?

Diversity patterns and ecological structure

In Sweden, IBA will describe insect and associated microbial communities across 200 replicate sites explicitly selected to represent the national ranges of habitats. We will thus be able to answer: what habitats and regions sustain the highest diversity of organisms when we include the truly diverse taxa. At a larger spatial scale, what patterns of regionally similar biotas can we distinguish? Answering the latter question will allow us to revisit the circumscriptions of biogeographic areas within Sweden, which are currently based mainly on their largest and most conspicuous inhabitants.

Beyond the mere description of patterns, our data will allow us to identify the key determinants of insect biodiversity. We will use advance modelling approaches to ask: what are the main determinants of diversity patterns: is it soil chemistry, vegetation characteristics, macro- or microclimate? For the latter purpose, we will measure basic descriptors of both biotic and abiotic conditions at each site. We will also relate current community structure to the contemporary landscape and recent changes in it by drawing on landscape-level descriptors available from other national monitoring initiatives. This holistic approach will allow us to identify what species groups and what species traits (such as size and other aspects of morphology, or life style) render a taxon particularly sensitive to its environment and to changes in it. Finally, we will be able to elucidate what species and species groups aggregate at the same sites or avoid each other.