The genomics of thermal adaptation in a model pest insect

点击翻译按钮获取中文摘要

One sixth of the world's crop production is lost to pests and diseases each year. Rises in global temperatures are expected to cause dramatic shifts in the range and abundance of food pests, with potentially alarming consequences for global food supplies. To protect food security in the context of a changing climate therefore requires multidisciplinary research into how pest species adapt to their environments, drawing from the fields of molecular biology, genetics, ecology and evolutionary biology. Understanding how organisms adapt to high temperature is especially important, as temperature increases affect organisms in a wide range of ways, from their DNA to their complex social behaviours.Combining the principles of Darwinian evolution with DNA sequencing is an excellent way of studying how pests adapt to temperature. Pest species usually have very short life-cycles, so can evolve rapidly in response to changing temperatures. Studying how pests evolve in response to temperature using DNA sequencing is a promising way forward because i) many of the characteristics and processes thought to be important for how pests adapt to temperature, such as body size, development and stress response, have a genetic basis; and ii) it will enable us to identify new genes, and new biological processes, involved in adapting to climate. At present, however, we know very little about what kinds of genes are involved in adapting to temperature, and less still about how rapidly these genes can evolve and allow pests to spread.I will study how food pests adapt to temperature. My study organism will be the red flour beetle, a major pest of stored grain that causes enormous amounts of wheat, rice and corn to be discarded each year. It is also a "model species" for DNA research, with detailed genetic information available, and is easy to rear and study in the laboratory. I will study how red flour beetles evolve in response to extreme temperatures in real time, using replicated populations that have been maintained in the laboratory at high temperature for 60 generations. By sequencing the genomes of individual flour beetles adapted to living at extreme temperatures, I will identify the genes and biological processes that govern adaptation to temperature, and find out how these genes interact with one another. Additionally, because I have samples available from every generation since this experiment was set up, I will be able to look at how genes involved in adaptation to temperature evolve over time, and in doing so determine how rapidly these important genes can respond to changing temperature.The proposed research will give us a better understanding of how DNA enables individuals and populations adapt to their environments. And, importantly, it will help us generate better predictions of where and when food pests are likely to spread as the global climate continues to change.