Accelerated invasion through the evolution of dispersal behaviour

Abstract

Aim The continuous spread of invasive species is attributed to demographic processes and high dispersal rates. Both can change and evolve during range expansion, eventually accelerating spread dynamics. Here, we document such an accelerated spread for one of the most invasive spiders in Europe, the dwarf spider Mermessus trilobatus, and test whether dispersal, reproduction or competitive ability is at the source of this pattern. Location Europe. Time period 1981–2021. Major taxon studied Mermessus trilobatus (Arachnida: Araneae: Linyphiidae). Methods First, we collected records from 21 countries across Europe to document the speed of progression of the invasion front over the last 40 years. Second, we collected live individuals from populations in the longest and more recently invaded areas and compared the dispersal propensity of offspring raised under standardized conditions. Third, we compared the reproduction and competitive ability of females derived from the populations of long‐invaded areas against areas with more recent establishment. Results The progression of the invaded range increased from about 150 km in the 1980s to some 400 km between 2010 and 2020. Dispersal‐related behaviour was nearly twice as frequent in offspring from invasion front populations compared to the core area. By contrast, we found no differences in reproduction or competitive ability among the studied populations. Further, neither joint inheritance nor trade‐offs of dispersal, reproduction or competitive ability were identified. Main conclusion As high dispersal is recessively inherited in M. trilobatus, our results suggest that the accelerated invasion is due to the accumulation of dispersive but not more reproductive or competitive genotypes in newly colonized areas. Given the high climatic amplitude of the species in North America, we expect it to spread over the remaining parts of Europe and large parts of Asia in the coming decades. Accelerated range expansion through the evolution of dispersal behaviour could play a role in numerous arthropod invasions worldwide.

Selection for greater dispersal in early life leads to faster age-dependent decline in locomotor activity and shorter lifespan

“…Previously several research, both theoretically and empirically, have demonstrated that indeed dispersal properties of a species can evolve rather rapidly under such congenial conditions (McPeek & Holt 1992;Hutson et al 2003;Fronhofer et al 2014;Tung et al 2018b). This evolution of greater dispersal properties can lead to a species becoming invasive, as is the case with Cane toads in Australia (Phillips et al 2008;Shine et al 2021) and dwarf spiders in Europe (Narimanov et al 2022), and pose a threat to native ecosystems.…”

“…2008; Shine et al . 2021) and dwarf spiders in Europe (Narimanov et al . 2022), and pose a threat to native ecosystems.…”

The first record of Diplocephalus graecus (Araneae: Linyphiidae) in Germany with comments on its range expansion

“…It is currently unclear what factors are driving the spread of D. graecus . Narimanov et al (2022) demonstrated that the invasive linyphiid Mermessus trilobatus (Emerton, 1882), originating from North America, benefits from high dispersal behavior, which appears to be the main driver of its rapid spread. However, this does not appear to be the primary factor driving the current spread of D. graecus .…”

“…Especially other agrobiont linyphiid species exhibiting activity during winter like Centromerita bicolor (Blackwall, 1833) (Blick et al 2003, Schaefer 1977), may be potentially affected. However, it is worth noting that the comparably sized M. trilobatus has invaded and established in similar habitats without having (measurable) negative effects on the local ecosystem until now (Eichenberger et al 2009, Narimanov et al 2021, 2022, De Smedt & Van Keer 2022).…”

Spiders (Araneae) from green roofs in north-west Switzerland – faunistic data with two species new to Switzerland

“…Today it can be found in every larger collection from any open habitat. Current overviews are given in Hirna (2017) and Narimanov et al (2022). In our investigation, the species was found in 28 sites on 15 buildings.…”