Microbial Experimental Ecology and Evolution Reading Group
The ability to evolve and adapt is a fundamental property of living systems. In many populations, the process of adaptive evolution can be thought of as an uphill walk of a population on a "fitness landscape" where mutations are steps and fitness is altitude. Understanding the structure of fitness landscapes is a fundamental open problem in evolutionary biology. I will discuss our efforts to probe the fitness landscapes and the adaptive walks on them using experimental microbial populations. I will show some interesting and perhaps somewhat counter intuitive patterns that we found.
Ecological communities are very complex systems comprising species that interact with each other in spatially extensive settings. Understanding the rules that govern these systems and how they behave in time is fundamental, but it is also of practical importance since it concerns the maintenance of biodiversity in the face of global change.
Populations often encounter environmental changes that remove selection for the maintenance of certain phenotypic traits. The resulting decay of these traits under relaxed selection reduces an organism’s fitness in its prior environment. However, how these traits subsequently evolve upon restoration of selection is not well-understood. We addressed this question using Escherichia coli strains from the long-term evolution experiment (LTEE) that have been independently evolving for multiple decades in the absence of antibiotics.
The emergence and worldwide dissemination of antibiotic resistant organisms represents a significant threat to global public health. An organism that epitomizes both the urgency and challenges associated with this threat is carbapenem-resistant Klebsiella pneumoniae (CRKP). CRKP was first observed in a clinical case in 1996, in a hospital in North Carolina. Since that time, successful lineages of CRKP have spread across the globe, becoming endemic in healthcare networks in many regions.
The tree of life is a foundational concept for the biological sciences. Over the last few decades, herculean efforts by researchers have dramatically increased the available data with which we can better understand the structure and the processes that shape evolutionary relationships. However, despite these advances, new challenges have emerged. Here, I describe several projects that aim to better reconstruct a more complete view of the complexity underlying phylogenies. Specifically, I demonstrate the extensive genome conflict present in virtually all genomic datasets.
EEB Tuesday Lunch Seminar
We are pleased to announce this year's Early Career Scientist Symposium, Frontiers in Community Assembly, to be held Saturday, March 12, 2016 in the Chemistry Building on the campus of the University of Michigan, Ann Arbor. The symposium will focus on the integration of evolutionary and ecological perspectives to understand community assembly.
EEB will be hosting an annual workshop that serves as a basic introduction to the R statistical package and language. This workshop is geared towards people with no (or extremely little) programming experience, and is generally taken by incoming students, but all in EEB are welcome. Please fill out the form below if you intend on participating.
Despite centuries of discovery, most of our planet's biodiversity remains unknown. The scale of the unknown diversity on Earth is especially troubling given the rapid and permanent loss of biodiversity across the globe. The goal of the Dimensions of Biodiversity campaign is to transform, by 2020, how we describe and understand the scope and role of life on Earth. This campaign promotes novel integrative approaches to fill the most substantial gaps in our understanding of the diversity of life on Earth.