Phylogenetic Comparative Methods Demonstrate the Non-Directional Evolution of Genomic Features in the Streptococcus Genus

Abstract

Streptococcus, a genus of Gram-positive bacteria, encompasses many species with diverse ecological roles, from commensals in the human microbiota to pathogens causing a spectrum of infections. Understanding the biology and evolution of Streptococcus is crucial for unraveling its significance in health and disease. In this paper, I shall study the trait evolution of 4 genomic features - Genome size, Genomic GC content, Genomic repeat fraction, and Number of coding genes in the Streptococcus genus. Using phylogenetic generalized least squares, I find a strong positive correlation between genome size and the number of coding genes, while other features are unrelated.