Clonal interference, genetic variation and the speed of evolution in structured populations

Area of Science:

• Evolutionary biology
• Population genetics
• Theoretical ecology

Background:

• Population structure is widely believed to reduce evolutionary rates and increase genetic variation due to interference between beneficial mutations.
• Previous models typically use simple structures like connected demes or lattices, which slow down selective sweeps.

Purpose of the Study:

• To investigate how varying population structure heterogeneity affects evolutionary rates and outcomes.
• To challenge the conventional understanding of population structure's impact on evolution.

Main Methods:

• Simulations of evolutionary processes on diverse population topologies.
• Analysis of selective sweep dynamics and mutation interference across different structures.

Main Results:

• Introducing heterogeneity in population structure can lead to increased rates of evolution.
• The evolutionary effects are highly dependent on the specific topological properties of the population structure.
• Prior conclusions about reduced evolutionary rates in structured populations may not universally apply.

Conclusions:

• The impact of population structure on evolution is critically dependent on its topological features.
• Heterogeneous structures can yield different evolutionary dynamics than simple or well-mixed models.
• Careful consideration of spatial properties is necessary for accurate evolutionary predictions and interpretations.