Broadly, my research focuses on estimating parameters of a population's demography from genetic data. Direct observations are often costly and time consuming, thus having methods that analyze nowadays often easily accessible genetic data can give valuable insights into current and past population structure.
Ancient DNA of Humans
In the last decade, a new fascinating application of such techniques has emerged. It has become feasible to extract and analyze DNA from ancient skeletal material (aDNA). A new field, termed archaeogenetics, has produced much new insight into long-standing questions about connectivity and migrations of past human cultures. This discipline connects two big personal interests of mine, human history and population genetics. I decided to establish a research career in this field, and in 2021 I started a position as a group leader in the Department of Archaeogenetics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, a leading center for sequencing and analysing human aDNA.
My work on aDNA focusses on two topics:
- Population Genetic analysis of aDNA data. By studying DNA of peoples who lived many generations ago, one can learn about past population history, for instance migrations, admixtures and population turnovers. Archaeogenetics has become an exciting new tool to learn about human population history.
- Creating new computational tools for studying aDNA data. Particularly, I am working on pushing powerful haplotype based methods to the low coverage DNA data typical for aDNA.
Demographic Inference using shared haplotypes
One particular interest of mine focuses on utilizing the power of IBD segments for demographic inference. These blocks are the genomic signposts of recent genealogical connections between two individuals; they are co-inherited identically from a recent common ancestor (hence Identical by Decent - IBD). Based on population genetic arguments, I envision that IBD segments can be an ideal ressource to infer key recent demographic parameters such as rates of mobility, connectivity and population size trajectories.
Method to infer IBD segments are commonly applied to modern DNA, e.g. IBD blocks are widely used in personal genomics to detect up to third degree cousins. However, the low-coverage regime typical of aDNA data is not accessible with standard IBD detection approaches. Therefore, currently, my group and I are working on making the next logical steps:
- Detecting IBD in aDNA with specifically developed and fine-tuned methods.
- Turning IBD segments inferred in aDNA into demographic estimates. For instance, one needs to develop new tools for time series data.
This progress will allow us to address key questions about the human past in a completely new way.
Snapdragon Hybrid Zone
I am involved in a project that focuses on a hybrid zone of Antirrhinum majus (snapdragons) in the Eastern Pyrenees. In this long-term project started in 2009, extensive sampling of a contact zone between two flower color morphs is conducted - with the goal to construct a pedigree to study selection and gene flow in this wild hybrid population. I am involved in field work since 2013, and every summer in my PhD I have spent a few weeks in a picturesque valley in north east Spain.
I am involved in data analysis of this project, where I primarily investigate the spatial patterns of genetic structure of this population. The aim is to understand whether indirect genetic methods agree with "direct" pedigree estimates. This will help to better understand how well methods that often make strong assumptions about population structure agree with the possibly very complex reality of natural populations.