Ecological genetics of the great tit in a new, long-term population study set along a rural-urban environmental gradient

Many important questions in ecology and evolutionary biology can only be answered with longitudinal data, which ideally takes into account several life-cycles of a given animal study system. However, virtually all long-term studies of vertebrates were started in natural environments with little or no human interference; our understanding of natural variation, response to selection and adaptation in wild animals living in urban environments is therefore particularly limited. Given that urban areas covered 0.5% of the planet’s and area in 2000 and are predicted to expand 12-fold between 2000 and 2050, more insight into the ecological genetics of free living animals in urban environments is sorely needed. To understand the footprint of cities on the phenotype and genotype of a wild passerine bird, this project aims to initiate a large-scale, long-term study of great tits Parus major in the city of Warsaw (Poland) along an urbanisation gradient. Since urban environments clearly impose novel selection pressures in stark contrast to forested landscapes great tits primarily occupy, five key research hypotheses (H) will be tested:

H1. In order to derive urbanisation gradients which have maximum explanatory power in analyses of phenotypic variation, biologically relevant data of the study system investigated needs to be accounted for.

H2. Environmental change observed along an urbanisation gradient induces changes in great tit phenotype.

H3. Selection on phenotypic traits varies in shape and /or intensity along an urbanisation gradient.

H4. Urban and rural birds differ in their genotypes. An increasing signal of urban genetic signatures of selection can be detected along the urbanisation gradient.

H5. Phenotypic, environmental and genetic information concur to support evidence towards adaptation for urban living.