Rapid evolution of phenology during plant invasion

A fully-funded PhD project is available in an exciting new collaboration between the Centre for Ecology & Hydrology and the University of Stirling. This project will develop new understanding of the role that rapid evolution plays in invasion and will focus on one of Europe’s most harmful alien plants.

Non-native species invasions are a major component of global change and are increasingly hazardous to biodiversity and society. It is speculated that rapid evolution during invasion might facilitate colonisation of new habitats, causing ‘niche shifts’ between native and invaded ranges. However, we lack understanding of the link between evolutionary change at ecological scales and the spread and impacts of invasive species at macroecological scales.

This PhD will investigate whether evolution of phenology facilitates invasion of ragweed (Ambrosia artemisiifolia), a crop weed introduced to southern Europe from North America. As well as impacting agricultural production, ragweed’s highly allergenic pollen causes major public health problems as a cause of hay fever and asthma.

At the current invasion front in southern Germany, ragweed is evolving earlier flowering. This may confer tolerance to cooler climates because earlier flowering provides more time for seed maturation before the growing season ends. However, earlier plants should also be smaller and therefore have fewer resources for producing allergenic pollen and seeds. The result is a life history trade-off between flowering phenology and fitness. We hypothesise that this trade-off will determine the extent to which rapid phenological evolution promotes ragweed’s onward invasion of northern Europe.

In the UK, ragweed cannot currently invade. Introduced seeds germinate but do not establish self-sustaining populations, presumably because of cool temperatures. Therefore, we urgently need to understand whether the evolution being observed at the invasion front is pre-adapting ragweed for invasion of the UK.

The central aims of the studentship are:
1. To quantify the rapid evolution in key phenology parameters occurring during ragweed’s invasion.
2. To quantify the trade-off between phenology and plant fitness.
3. To use this to model the region of Europe that is currently at risk of ragweed invasion, and the region likely to become invaded under future climate change scenarios.

This studentship will deliver new scientific understanding and predictive ability for the risk of invasion by a serious threat to public health and agriculture. Moreover, we will help to develop a framework for alien species risk assessment, accounting for evolutionary change during invasion.

The studentship will start in September 2015, with the PhD awarded by the University of Stirling. The student will be based in Stirling (Dr Vallejo-Marin) for the first two years, and will then spend the final 18 months at CEH Edinburgh (Dr Chapman), working closely with CEH Wallingford (Prof James Bullock, providing CASE support). She/he will receive training in plant growth trials (experimental design, growth chambers, measurement and statistical analysis) and computational modelling of phenology at macroecological scales.

Essential skills are a minimum 2:1 BSc (or equivalent in Life Sciences), with good numerate skills and a strong enthusiasm for ecology and evolution. Desirable skills are statistical analysis using GIS and/or R software, experimental experience and experience in communicating science to a broad audience.

For full details of eligibility and how to apply, please see http://www.iapetus.ac.uk/aboutstudentships/. Further details of the project can be found at http://www.iapetus.ac.uk/wp-content/uploads/2014/11/IAP_14_13-CEH-Chapman.pdf.