The amount of urbanized land surface on earth is expected to triple by 2030, casting great pressure on organisms that live in cities. Natural habitats are becoming increasingly fragmented, decreasing the population sizes of wild animals and plants and increasing their isolation. In cities, multiple stress factors are present, such as a higher temperature, more light and air pollution.
Our question is how urban plant populations cope with these changes. Initial evidence indicates that some species rapidly evolve and adapt to urban environments. The new research field of urban evolution is studying this process.
Background and context
We use dandelion (Taraxacum officinale) to compare the dispersal capacity of plant populations in the city center with those in rural areas. Preliminary results indicate that fruit (the achenes) and pappus (the hairs, parachute) have a different weight, beak length, branching and fall speed in the city as compared with surrounding rural areas. Available genome and transcriptome data allows for testing the expression levels of underlying genes. Time travel studies will be conducted by studying herbarium specimens collected in rural areas up to two hundred years ago that have since been transformed into urban environments.
The aim is to analyze morphological differences in achenes and pappus from rural versus urban populations of dandelion and associated molecular changes. Projects thus include more morphological or molecular aspects to:
i. compare present-day rural versus urban populations
ii. compare herbarium specimens with contemporary dandelion growing at the same locality
A selection of methods ranging from microscopic analysis (light, transmission electron and micro CT-microscopy) to DNA- and RNA-isolation, PCR, RNAseq/qPCR, and statistics will be applied.
Having an interested in plant development and evolution, have an interest in one or more of the methods, being patient and precise.