Positive diversifying selection is a pervasive adaptive force throughout the Drosophila radiation

Area of Science:

• Evolutionary Biology
• Genomics
• Biodiversity Research

Background:

• Genomic information on non-model organisms aids evolutionary studies.
• Drosophila species diversity makes them key for adaptive radiation research.
• Recent increases in sequenced Drosophila species enhance evolutionary insights.

Purpose of the Study:

• To conduct a genome-wide analysis of positive diversifying selection in Drosophila.
• To identify genes and biological processes influenced by positive selection across 25 species.
• To investigate the role of selection in shaping species-specific adaptations and diversity.

Main Methods:

• Genome-wide analysis of over 2000 single-copy orthologous groups.
• Utilized a novel, high-accuracy method for detecting positive diversifying selection.
• Compared selection signals across 25 Drosophila species.

Main Results:

• Identified 1342 single-copy orthologous groups (1.9% of loci) with a putative signal of positive diversifying selection.
• Found consistent selection signals throughout the Drosophila genus.
• Detected strong signals related to development and function in D. grimshawi lineages, and recurrent signals in aging and lifespan genes.

Conclusions:

• Positive diversifying selection has consistently promoted species-specific differentiation in Drosophila.
• Selection has acted on various biological processes, driving functional diversity and adaptive divergence.
• This study highlights the significant role of positive selection in shaping Drosophila evolution and diversity, including lifespan variation.