European Commission logo
English English
CORDIS - EU research results

Reproductive isolation and competitive ability between native and non-native ranges of invasive weeds

Final Report Summary - REPROWEED (Reproductive isolation and competitive ability between native and non-native ranges of invasive weeds.)

In a nutshell, project ReproWeed intended to understand the processes through which invasive species attain different success across very distinct native and non-native regions. We focused on local adaptation of traits, with a strong emphasis on changes on reproductive systems (thus the acronym). We were very successful on identifying key traits but, we also found that many of those key trait-shifts between native and non-native ranges (e.g. increased biomass of invasive Centaurea solstitialis populations) were also present for other non-invasive exotic species (e.g. the non-invasive co-generic species C. sulphurea and C. calcitrapa, published at PLOS ONE). We found that the many different local adaptations developing on each native and non-native region was paralleled by an incipient degree of reproductive isolation, which suggests that invasives’ allopatric distribution could in fact be subjected to the same processes believed to shape the early stages of allopatric speciation (published at The American Naturalist). When we studied the fitness of experimentally produced inter-regional hybrids between Spain and California, we found that such inter-regional hybrids presented intermediate competitive ability when compared from their parents from their native and non-native regions (published at Ecography). This suggests that potential reintroductions from the native range would likely diminish competitive ability of locally adapted individuals by introducing maladapted genomes from the native range.

Additionally, we also participated on the description of the phylogeography of most of the world range of the species, a critical information which was lacking on the literature and that will surely become a necessarily citation for most studies about the species (published at PLOS ONE). Data indicates that the geographical origin of the species (where the species first appeared in evolutionary history) was Turkey and Georgia, from where it likely spread through southern Europe until Spain. It is precisely this country, Spain, the most likely origin for invasions into North and South America, although later reintroductions from other European regions likely also occurred after the initial arrival.

Finally, we gathered our data to build models which allowed us to integrate different data sources to understand which traits would be more important for invasive success. Our models showed that C. solstitialis plants from California were better competitors but that, regardless of origin, significant levels of disturbance in the invaded habitat were necessary for the species to dominate the community (published at Ecological Modelling). This information will be critical for the development of management plans, and emphasizes the prevalence of dynamic environmental conditions over the importance of being locally adapted.

As a researcher, the fellowship, and the career advising committee emerging from it, have significantly contributed to my progress towards stabilization into the European Research Area. I have been able to publish 15 scientific papers during the grant, and have several manuscripts more either under review or in preparation. I successfully obtained external funding from my host country’s science foundation (FCT-Portugal) adding up to nearly €270 000 in two research projects, one of them still ongoing. I also obtained a renewable (upon new competition) five-year contract as full time researcher at the host institution (University of Coimbra). I also supervised one M.Sc. student and one Ph.D. student (ongoing). The grant also allowed me to develop a continuous outreach program, with resulted in high-quality direct interactions with hundreds of people of all ages, plus many more via magazine articles and blogging.