Historically, food web have been grouped in trophic groups. However, recent algorithms identified modules in food webs. Using a novel algorithm detecting trophic groups, we show that trophic groups are better descriptors of food web structure than modules. We further reveal a hierarchical structure of food webs: modules partition food webs into different energetic pathways, then partitioned into trophic groups.

Anthropogenic threats influence the structure of interaction networks. Body size can predict predator-prey interactions, but competition is seldom included in ecological networks. I observed dung-associated-community interactions in protected and unprotected areas of an Afromontane forest reserve. The competition network structure changed in protected areas of the forest, and the outcome of interactions was influenced by body-size ratios between competitors.

Carnivore species can have positive indirect effects on each other, which increases the persistence of populations. Overharvesting of one carnivore species may therefore lead to cascading extinctions of other carnivores. We demonstrate this effect in experimental insect communities, with carnivore species seperated by four trophic links, illustrating a mechanism for horizontal extinction cascades.

In a theoretical approach, we show the robustness of relationships between network complexity and stability to the interconnection: mutualistic complexity fosters stability, in contrast with antagonistic complexity. These effects are not restricted to each sub-network, as the two sub-networks influence each other through cascading extinctions. Thus, considering interconnection between different network types is key to understanding species persistence.

We introduce Cheddar - a flexible R package that provides a comprehensive range of food-web analyses and plots, focussing on data that are augmented with estimates of body mass and numerical abundance. This unified package has the potential to improve research efficiency and to serve as a unified framework for future development.

A manipulative field experiment was carried out in Lough Hyne marine reserve to examine the effect of diversity loss at multiple trophic levels. Impacts on species richness, number of trophic links, food chain length and connectance were detected, with the lowest levels occurring after the loss of diversity from just one trophic level.

River habitat enhancement is often used to reinstate ecosystem properties. To test the effectiveness of large woody debris as a restoration tool, five chalk streams were sampled before and after at control and treatment sites. Food web properties including connectance, complexity and allometric scaling have been used to measure community response.

How can we assess the importance of individual species within ecological networks (e.g. food webs)? Here we demonstrate a novel way of assessing importance and show how the importance of individual plant species relates to their traits. We use field data of a farmland food web with plants and 12 animal guilds and comprising trophic, mutualistic and parasitic interactions.