Where is genetic material sharing concentrated across related warbler species genomes?

In specific regions, suggesting some parts of the genome are more permeable to gene flow than others.

Research into the genetic architecture of related warbler species indicates that the sharing of specific DNA segments (gene flow) is not a random event across the entire genome. Instead, the sharing appears concentrated in specific regions. This structured pattern implies that certain segments of the genome possess higher permeability to gene flow between lineages than others. Segments under strong, unique selection pressure, such as those controlling adaptations critical for diet like beak shape, are less likely to be shared widely. Conversely, genes controlling traits under more generalized or weaker selection pressures are more likely to exhibit this shared variation across evolutionary neighbors.