Congruent mammalian trees from mitochondrial and nuclear genes using Bayesian methods.

Area of Science:

• * Molecular evolution and phylogenetics
• * Mammalian genomics and systematics

Background:

• * Discrepancies between mitochondrial and nuclear gene trees have challenged molecular phylogenetics in mammals.
• * Traditional morphological classifications have also faced challenges due to conflicting molecular data.

Purpose of the Study:

• * To reinvestigate mammalian phylogenetic relationships using newly sequenced mitochondrial genomes.
• * To assess the congruence between gene trees and the underlying species phylogeny.

Main Methods:

• * Bayesian phylogenetics was employed to analyze gene sequences.
• * Complete mitochondrial genomes of Spalax judaei, Jaculus jaculus (rodents), and Ochotona princeps (lagomorph) were sequenced and analyzed.

Main Results:

• * Phylogenetic relationships derived from mitochondrial genomes were highly congruent with previous nuclear gene analyses.
• * Four primary lineages of placental mammals were identified: Xenarthra, Afrotheria, Laurasiatheria, and Euarchontoglires.
• * The relationships within and between these lineages suggest gene trees align with the species phylogeny.

Conclusions:

• * Molecular data, particularly from complete mitochondrial genomes, can provide robust and congruent phylogenetic insights.
• * The identified four primary lineages represent a well-supported framework for understanding placental mammal evolution.
• * Reconciling gene trees with species phylogeny is achievable with comprehensive genomic data and advanced analytical methods.