Human activity has altered the evolution of a huge number of species. Some species however are able to adapt, survive and persist to the world that we created. Most notable among these are human commensal species, animals which are dependent on human resources but have arisen without any active intervention from humans. There are widespread examples – rats, mice, microbes and lice. Despite the familiarity of these species to us, we know surprisingly little about the evolutionary origins of human dependent relationships. We also don’t have a good appreciation of the impact that such relationships have on the biology of the animals involved.
The EVOSPARROW project was designed to address this knowledge gap and to examine human commensalism in an evolutionary framework. The project focuses on a familiar, charismatic group of species – Passer sparrows. These include the house sparrow (P. domesticus), a widespread and well-known human commensal bird species. Sparrows were chosen because they are closely associated with humans and there is a good foundation of biological knowledge on them. Furthermore, recent research efforts have established genomic tools that make it possible to investigate the provenance of this widespread bird.
The overarching aim of EVOSPARROW is to investigate how commensalism arose in Passer sparrows and to investigate the evolutionary consequences this shift to a human dependent niche has had on the species. Using genomic and phenotypic data, the project aimed to disentangle the evolutionary history of Passer species, reconstruct the evolutionary history of Passer sparrows in Europe and finally identify the genomic basis of phenotypes involved with adaptation to a human commensal life history.
Human commensal species can have profound effects on human society. For example, commensalism may be a pathway to domestication (i.e. dogs) or may lead to the development of pest species such as mice. Investigating commensalism in an evolutionary context has two major values to society. Firstly, an understanding of the origin of such species and the traits that allow them to adapt to human environments can provide important insight into methods for managing their impacts. Secondly, the history of these species are often closely entwined with our own – by piecing together how these species came to be, we are also able to reflect on major transitions and changes in human society.
