Browsing by Author "Kenis, Marc"

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    Global population genetic structure and demographic trajectories of the black soldier fly, Hermetia illucens
    (BMC, 2021-05-05) Kaya, Cengiz; Generalovic, Tomas N.; Ståhls, Gunilla; Hauser, Martin; Samayoa, Ana C.; Nunes-Silva, Carlos G.; Roxburgh, Heather; Wohlfahrt, Jens; Ewusie, Ebenezer A.; Kenis, Marc; Hanboonsong, Yupa; Orozco, Jesus; Carrejo, Nancy; Nakamura, Satoshi; Gasco, Laura; Rojo, Santos; Tanga, Chrysantus M.; Meier, Rudolf; Rhode, Clint; Picard, Christine J.; Jiggins, Chris D.; Leiber, Florian; Tomberlin, Jeffery K.; Hasselmann, Martin; Blanckenhorn, Wolf U.; Kapun, Martin; Sandrock, Christoph
    Background: The black soldier fly (Hermetia illucens) is the most promising insect candidate for nutrient-recycling through bioconversion of organic waste into biomass, thereby improving sustainability of protein supplies for animal feed and facilitating transition to a circular economy. Contrary to conventional livestock, genetic resources of farmed insects remain poorly characterised. We present the first comprehensive population genetic characterisation of H. illucens. Based on 15 novel microsatellite markers, we genotyped and analysed 2862 individuals from 150 wild and captive populations originating from 57 countries on seven subcontinents. Results: We identified 16 well-distinguished genetic clusters indicating substantial global population structure. The data revealed genetic hotspots in central South America and successive northwards range expansions within the indigenous ranges of the Americas. Colonisations and naturalisations of largely unique genetic profiles occurred on all non-native continents, either preceded by demographically independent founder events from various single sources or involving admixture scenarios. A decisive primarily admixed Polynesian bridgehead population serially colonised the entire Australasian region and its secondarily admixed descendants successively mediated invasions into Africa and Europe. Conversely, captive populations from several continents traced back to a single North American origin and exhibit considerably reduced genetic diversity, although some farmed strains carry distinct genetic signatures. We highlight genetic footprints characteristic of progressing domestication due to increasing socio-economic importance of H. illucens, and ongoing introgression between domesticated strains globally traded for large-scale farming and wild populations in some regions. Conclusions: We document the dynamic population genetic history of a cosmopolitan dipteran of South American origin shaped by striking geographic patterns. These reflect both ancient dispersal routes, and stochastic and heterogeneous anthropogenic introductions during the last century leading to pronounced diversification of worldwide structure of H. illucens. Upon the recent advent of its agronomic commercialisation, however, current human-mediated translocations of the black soldier fly largely involve genetically highly uniform domesticated strains, which meanwhile threaten the genetic integrity of differentiated unique local resources through introgression. Our in-depth reconstruction of the contemporary and historical demographic trajectories of H. illucens emphasises benchmarking potential for applied future research on this emerging model of the prospering insectlivestock sector.
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    Troubling travellers : are ecologically harmful alien species associated with particular introduction pathways?
    (Pensoft Publishers, 2017) Pergl, Jan; Pysek, Petr; Bacher, Sven; Essl, Franz; Genovesi, Piero; Harrower, Colin A.; Hulme, Philip E.; Jeschke, Jonathan M.; Kenis, Marc; Kuhn, Ingolf; Perglova, Irena; Rabitsch, Wolfgang; Roques, Alain; Roy, David B.; Roy, Helen E.; Vila, Montserrat; Winter, Marten; Nentwig, Wolfgang
    Prioritization of introduction pathways is seen as an important component of the management of biological invasions. We address whether established alien plants, mammals, freshwater fish and terrestrial invertebrates with known ecological impacts are associated with particular introduction pathways (release, escape, contaminant, stowaway, corridor and unaided). We used the information from the European alien species database DAISIE (www.europe-aliens.org) supplemented by the EASIN catalogue (European Alien Species Information Network), and expert knowledge. Plants introduced by the pathways release, corridor and unaided were disproportionately more likely to have ecological impacts than those introduced as contaminants. In contrast, impacts were not associated with particular introduction pathways for invertebrates, mammals or fish. Thus, while for plants management strategies should be targeted towards the appropriate pathways, for animals, management should focus on reducing the total number of taxa introduced, targeting those pathways responsible for high numbers of introductions. However, regardless of taxonomic group, having multiple introduction pathways increases the likelihood of the species having an ecological impact. This may simply reflect that species introduced by multiple pathways have high propagule pressure and so have a high probability of establishment. Clearly, patterns of invasion are determined by many interacting factors and management strategies should reflect this complexity.