Introgression between highly divergent fungal sister species

Area of Science:

• Evolutionary Biology
• Population Genetics
• Mycology

Background:

• Gene flow and introgression significantly influence speciation and adaptive radiation.
• Understanding these processes is crucial for comprehending species evolution in changing environments.

Purpose of the Study:

• To investigate gene flow and introgression between two closely related fungal sister species.
• To develop and utilize a novel experimental system for studying these mechanisms in natural populations.

Main Methods:

• Whole genome sequencing of fungal populations from North America and Europe.
• Assessment of genome-wide nucleotide divergence and reproductive barriers through crossing experiments.
• Application of ABBA-BABA statistics, network analysis, and demographic modeling.

Main Results:

• The fungal sister species are highly divergent and reproductively incompatible in vitro.
• Despite divergence, small introgressed regions were identified across their genomes.
• Evidence suggests one introgression event may involve a ghost population.

Conclusions:

• Introgression can occur between highly divergent species, challenging previous assumptions.
• The developed experimental system effectively studies reproductive isolation and population histories in natural settings.
• Findings contribute to understanding species adaptation and evolutionary dynamics.