Comparative phylogeography of the ocean planet

Area of Science:

• Marine Biology
• Evolutionary Genetics
• Biogeography

Background:

• Marine biodiversity is influenced by geographical, oceanographical, and climatic factors.
• Understanding these influences requires aligning genetic diversity patterns across various marine taxa.
• Biogeographic provinces are defined by species composition, endemism, and taxonomy.

Purpose of the Study:

• To examine phylogeographic partitions in marine environments.
• To assess the concordance between marine biogeographic provinces and genetic diversity distributions.
• To explore how geographical and climatic factors shape marine genetic diversity and speciation.

Main Methods:

• Comparative phylogeography across diverse marine taxa and regions (tropical, temperate, migratory, plankton).
• Analysis of genetic diversity partitions in relation to established biogeographic boundaries.
• Examination of genotype frequency shifts across biogeographic provinces.

Main Results:

• Strong interspecific concordance observed, where genetic differences between sister species align with biogeographic provinces.
• Intraspecific concordance demonstrated, with genotype frequencies shifting at biogeographic boundaries for widespread species.
• Both tropical and temperate seas show impacts of glacial cycles, affecting sea levels and coastal habitats respectively.

Conclusions:

• The general concordance between biogeography and phylogeography highlights population-level genetic divergence as a precursor to macroevolution.
• Isolation between provinces is a significant driver of marine biodiversity, but not the sole factor.
• Alternative evolutionary pathways, including ecological speciation and parapatric divergence within provinces, also contribute to marine biodiversity.