Digest: Mating systems, intragenomic conflict, and speciation.

Area of Science:

• Evolutionary biology
• Genetics
• Reproductive biology

Background:

• Parental conflict arises from differing genetic interests between maternally and paternally inherited alleles regarding offspring investment.
• This conflict is generally absent in self-fertilizing species.
• Understanding reproductive incompatibility is key to understanding speciation.

Purpose of the Study:

• To investigate how divergence in parental conflict between closely related outcrossing and selfing species influences hybrid development.
• To explore the role of parent-offspring conflict in driving reproductive isolation and speciation.

Main Methods:

• Comparative analysis of closely related morning glory species with differing mating systems (outcrossing vs. selfing).
• Examination of early developmental stages in interspecific hybrids.
• Genetic and molecular analyses to assess allele-specific gene expression and imprinting patterns.

Main Results:

• Hybrids between outcrossing and selfing morning glory species exhibit aberrant early development.
• Divergence in the intensity of parent-offspring conflict between species correlates with developmental abnormalities in hybrids.
• Evidence suggests that genomic imprinting, a key mechanism in parent-offspring conflict, differs between the studied species.

Conclusions:

• Divergent parent-offspring conflict, driven by differing mating systems, can lead to hybrid developmental errors.
• These developmental errors contribute to reproductive incompatibility, acting as a significant factor in speciation.
• The study highlights parent-offspring conflict as a potent evolutionary force shaping reproductive isolation.