We summarize the current knowledge on parasitism-related invasion processes of the globally invasive Rattus lineages, originating from Asia, and how these invasions have impacted the local epidemiology of rodent-borne diseases. Parasites play an important role in the invasion processes and successes of their hosts through multiple biological mechanisms such as "parasite release", "immunocompetence advantage", "biotic resistance" and "novel weapon".Parasites may also greatly increase the impact of invasions by spillover of parasites and other pathogens, introduced with invasive hosts, into new hosts potentially leading to novel emerging diseases. Another potential impact is the ability of the invader to amplify local parasites by spill-back. In both cases, local fauna and humans may be exposed to new health risks, which may decrease biodiversity and may potentially cause increases in human morbidity and mortality. Here we review the current knowledge on these processes and propose some research priorities.

Gordius chiashanussp. nov., a newly described horsehair worm that parasitizes the Spirobolus millipede, is one of the three described horsehair worm species in Taiwan. It is morphologically similar to G. helveticus Schmidt-Rhaesa, 2010 because of the progressively broadening distribution of bristles concentrated on the male tail lobes, but it is distinguishable from G. helveticus because of the stout bristles on the mid-body. In addition, a vertical white stripe on the anterior ventral side and areoles on the inside wall of the cloacal opening are rarely mentioned in other Gordius species. Free-living adults emerged and mated on wet soil under the forest canopy in the winter (late November to early February) at medium altitudes (1100–1700 m). Mucus-like structure covering on the body surface, which creates a rainbow-like reflection, might endow the worm with high tolerance to dehydration. Although Gordius chiashanussp. nov. seems to be more adaptive to the terrestrial environment than other horsehair worm species, cysts putatively identified as belonging to this hairworm species found in the aquatic paratenic host, Ephemera orientalis McLachlan, 1875, suggest the life cycle of Gordius chiashanussp. nov. could involve water and land. The free-living adults emerged from the definitive hosts might reproduce in the terrestrial environment or enter an aquatic habitat by moving or being washed away by heavy rain instead of manipulating the behavior of their terrestrial definitive hosts.

A food web is a representation of trophic interactions in an ecosystem. Food webs are often generated by a single dataset aggregated from one or several surveys. Point estimates of food web parameters can be calculated from the data, but it remains an open question as to how their corresponding interval estimates can be quantified. Although conventional methods such as bootstrapping represent potential solutions, they tend to underestimate several network parameters. Here, we propose a simple bootstrap‐based resampling procedure for inferring food web parameters. First, for a particular food web parameter, we obtain its point estimate by calculating the corresponding statistics from the original food web. Second, we generate a resampled food web by sampling with replacement the same number of species from the original food web, and for each resampled species we record how many prey items it consumes in the original food web. Third, a resampled species is allowed to consume its original prey species if such a species is also present; if not present, it instead consumes the resampled species that is most topologically similar to its original prey species. Many resampled food webs can be generated in this manner, and we calculate particular food web statistics for each of them. These form a sampling distribution from which interval estimates of the true food web parameter can be determined. We demonstrate our methodology on two different food web datasets and discuss its application in comparing food webs of various sizes and connectance.

Understanding the mechanism shaping species assemblages is a fundamental goal in ecology. In the past, two hypotheses have been suggested. One is the filtering hypothesis, where environmental factors select for species of similar traits such that they co-occur in similar niches. The other is the competitive exclusion hypothesis, where related species are driven far apart by competition such that they overdisperse across various niches. Here, we investigate the relationship between species assemblages and their phylogenetic relatedness from a network perspective by using five separate ecosystems ranging from oceans to an inland lake. We quantified the similarity in species network positions in a food web and clustered them into different trophic role groups; using an online database, we quantified their phylogenetic distances. We then investigated whether related species tend to underdisperse or overdisperse across different trophic role groups. In general, our results suggest that the environmental filtering process is the dominant force shaping the species assemblage of those ecosystems. However, there are some possible cases where related species are driven by competition such that they evolve to adopt different trophic roles in relatively closed ecosystems.

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