Phylotranscriptomic analysis of the origin and early diversification of land plants

TLDR

Early branching events in land plant diversification and related algal lineages remain unresolved, and accurate reconstructions are essential for testing hypotheses about key traits such as embryos, vascular tissue, seeds, and flowers. The study investigates relationships among streptophyte algae and land plants using the largest nuclear gene set applied to this problem to date. The authors rigorously tested hypothesized relationships with a series of analyses designed to assess systematic errors from sampling artifacts and model misspecification. The results support some accepted phylogenetic hypotheses while rejecting others, establishing a new framework for studying land plant evolution.

Abstract

Significance Early branching events in the diversification of land plants and closely related algal lineages remain fundamental and unresolved questions in plant evolutionary biology. Accurate reconstructions of these relationships are critical for testing hypotheses of character evolution: for example, the origins of the embryo, vascular tissue, seeds, and flowers. We investigated relationships among streptophyte algae and land plants using the largest set of nuclear genes that has been applied to this problem to date. Hypothesized relationships were rigorously tested through a series of analyses to assess systematic errors in phylogenetic inference caused by sampling artifacts and model misspecification. Results support some generally accepted phylogenetic hypotheses, while rejecting others. This work provides a new framework for studies of land plant evolution.